Reverse Left Atrial Remodeling After Balloon Mitral Valvuloplasty in Severe Rheumatic Mitral Stenosis: A Cardiac Magnetic Resonance Study

Reverse Left Atrial Remodeling After Balloon Mitral Valvuloplasty in Severe Rheumatic Mitral Stenosis: A Cardiac Magnetic Resonance Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Reverse Left Atrial Remodeling After Balloon Mitral Valvuloplasty in Severe Rheumatic Mitral Stenosis: A Cardiac Magnetic Resonance Study Mary Atef Mishriky, Soha Romeih, Michael Gergis, Kerolos Shaker, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9465249/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Background Rheumatic mitral stenosis (MS) leads to chronic left atrial (LA) pressure overload, resulting in atrial enlargement and progressive impairment of reservoir, conduit, and contractile function. Although balloon mitral valvuloplasty (BMV) effectively relieves valvular obstruction, the extent of subsequent LA reverse remodeling remains incompletely defined. We aimed to evaluate changes in LA structure and phasic function after successful BMV using cardiac magnetic resonance (CMR). Results Forty-nine patients with isolated severe rheumatic MS underwent CMR before and 9–12 months after successful BMV, defined as a post-procedural mitral valve area ≥ 1.5 cm² without more than mild mitral regurgitation. Age- and sex-matched healthy individuals served as controls. At baseline, patients demonstrated significant LA enlargement and marked impairment of volumetric and deformation-derived reservoir, conduit, and contractile function compared with controls. Following BMV, indexed LA volumes decreased significantly, with parallel improvement in all phasic functional components. Recovery was most pronounced in LA reservoir and contractile strain indices, which approached normal values. In contrast, LA volumes and volumetric functional parameters remained significantly abnormal relative to controls. Conclusion Successful BMV was associated with meaningful but incomplete LA reverse remodeling within the first year after intervention. Functional recovery may precede full structural normalization after relief of chronic atrial pressure overload. CMR assessment of LA remodeling may provide clinically relevant insight into cardiac recovery and longitudinal follow-up after BMV in patients with rheumatic MS. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Introduction Mitral stenosis (MS), most commonly of rheumatic etiology, is characterized by chronic obstruction to left ventricular inflow, leading to sustained elevation of left atrial (LA) pressure and progressive impairment of atrial structure and function. ( 1 ) Long-standing pressure overload results in LA dilatation, wall fibrosis, reduced compliance, and deterioration of phasic atrial functions, including reservoir, conduit, and contractile components. ( 2 ) ( 3 ) These changes are closely linked to adverse clinical outcomes such as atrial fibrillation, thromboembolic events, and heart failure, making assessment of LA remodeling an important marker of disease severity and clinical risk in MS. ( 4 ) ( 5 ) Balloon mitral valvuloplasty (BMV) is the treatment of choice for patients with symptomatic severe rheumatic mitral stenosis (MS) and favorable valve morphology, providing immediate relief of transmitral obstruction and reduction of left atrial (LA) pressure. ( 6 ) Previous studies have demonstrated reductions in LA dimensions and volumes following successful BMV, predominantly using two-dimensional and three-dimensional echocardiography, with most investigations limited to immediate or short-term follow-up. ( 7 ) ( 8 ) However, LA volumetric parameters are highly load dependent and may not fully capture intrinsic myocardial recovery, particularly in the mid- to long-term period after intervention. ( 9 ) Cardiovascular magnetic resonance (CMR) is considered the gold standard for the assessment of cardiac chamber volumes due to its high spatial resolution and excellent reproducibility, allowing accurate quantification of LA size and remodeling. ( 10 ) Furthermore, CMR feature tracking (FT) applied to routine cine images enables comprehensive evaluation of LA phasic deformation, providing load-independent insights into atrial myocardial function. ( 11 ) Despite its potential advantages, data on CMR-derived LA volumetric and deformation changes following BMV remain limited. The aim of this study was to assess mid-term changes in left atrial structure and phasic function following successful balloon mitral valvuloplasty using CMR-derived volumetric and deformation parameters, and to compare these findings with healthy controls. Secondary objectives included evaluating the relationship between mitral stenosis severity and LA functional indices. Methods Study Design and Population This observational cohort study was conducted at Aswan Heart Centre, a tertiary care referral center in Upper Egypt. Between December 2017 and December 2022, 68 consecutive patients with symptomatic severe rheumatic mitral stenosis were screened for inclusion. In addition, 30 age- and sex-matched healthy individuals without known cardiovascular disease were prospectively recruited as a control group. Patients were eligible for inclusion if they had symptomatic rheumatic mitral stenosis in sinus rhythm, a mitral valve area (MVA) < 1.5 cm², and favorable valve morphology based on standard echocardiographic scoring systems, and subsequently underwent balloon mitral valvuloplasty (BMV). Successful BMV was defined as achievement of a post-procedural MVA ≥ 1.5 cm² in the absence of more than mild mitral regurgitation. Exclusion criteria included inadequate post-procedural valve dilation (MVA < 1.5 cm²), development of moderate or severe mitral regurgitation, atrial fibrillation at baseline or during follow-up, prior cardiac surgery, uncontrolled systemic hypertension, advanced systemic disease, or any condition known to independently affect left atrial function. Imaging Protocol CMR Protocol Image Acquisition Cardiovascular magnetic resonance imaging was performed using a 1.5-T scanner (Magnetom Aera, Siemens Medical Systems, Erlangen, Germany) with retrospective electrocardiographic gating. All images were acquired during breath-holding using balanced steady-state free precession (bSSFP) sequences. Standard cine images were obtained in vertical long-axis two- and four-chamber views and in contiguous short-axis planes covering both ventricles from the base to the apex (12–14 slices).Typical imaging parameters included a flip angle of 50–70°, slice thickness of 6–8 mm with no interslice gap, matrix size of 160 × 256, field of view of 350–400 mm, repetition time of 3.2–3.8 ms, echo time of 1.6–1.9 ms, and a temporal resolution of approximately 25 ms. CMR Image Analysis All CMR datasets were analyzed using dedicated post-processing software by experienced observers blinded to clinical and echocardiographic data. Left Atrial Volumetric Analysis Left atrial (LA) volumes were quantified using the biplane area–length method from two- and four-chamber cine images. (Figs. 1 and 2). Semi-automated tracing of the LA endocardial borders was performed at different phases of the cardiac cycle, including the left atrial appendage while excluding pulmonary veins. LA volume was calculated using the formula: LA volume (mL) = 0.85 × A2C × A4C / L , (12) where A2C and A4C represent the LA areas in the two- and four-chamber views, respectively, and L is the shorter long-axis LA length measured from the atrial roof to the midpoint of the mitral annulus. ( 12 ) LA volumes were measured at: Maximum LA volume (LA Vmax) : at left ventricular end-systole Pre-atrial contraction volume (LA Vpre-A) : at late LV diastole immediately before atrial contraction Minimum LA volume (LA Vmin) : at LV end-diastole following atrial contraction All volumes were indexed to BSA. LA size assessment was therefore based on two-dimensional measurements rather than three-dimensional volumetric acquisition, a limitation acknowledged in the interpretation of results. Volumetric indices of LA phasic function were calculated as follows: • Total (reservoir) emptying fraction: (LAVmax − LAVmin) / LAVmax × 100 • Passive (conduit) emptying fraction: (LAVmax − LAVpre-A) / LAVmax × 100 • Active (booster pump) emptying fraction: (LAVpre-A − LAVmin) / LAVpre-A × 100 Figure (1) LA tracing in 4 and 2 chamber views. LA length is taken as the shorter long axis length (From atrial surface to midpoint of mitral annular plane). Control subject no. 4 Figure (2) Left atrial tracking in the 4-chamber view in a patient with severe rheumatic mitral stenosis (Study Patient no. 22) Left Atrial Feature-Tracking Analysis LA strain and strain-rate parameters were derived from bSSFP cine images using feature-tracking software (MASS MR Analytical Software System, version 2021-EXP, Leiden University Medical Center, the Netherlands). Images were exported in DICOM format for offline analysis. LA endocardial borders were manually delineated on two- and four-chamber cine images at LV end-systole and end-diastole. Manual adjustments were performed when necessary to ensure optimal tracking and to exclude pulmonary veins. Following application of the automated tracking algorithm, contours were propagated throughout the cardiac cycle. (Fig. 3). Tracking quality was visually inspected on a segmental basis. Figure (3) CMR LA Feature tracking. The figure shows a representative example of LA tracking in the 4 chamber view in control subject no. 4 Global LA deformation parameters were calculated by averaging values from six atrial segments. (Figs. 4, 5). The following strain components were analyzed: Reservoir strain (εR) : reflecting LA reservoir function during ventricular systole Conduit strain (εCD) : reflecting passive LA emptying during early ventricular diastole Contractile strain (εCT) : reflecting active LA booster pump function during late ventricular diastole Corresponding strain-rate parameters included: SRs : peak positive strain rate (reservoir function) SRe : peak early negative strain rate (conduit function) SRa : peak late negative strain rate (contractile function) Figure (4) Strain curves for the six segments of LA (Left). Average strain curve for all segments (Right). Control subject no. 4 Figure (5) LA strain and strain rate profiles (Control subject no. 4) LA functions were assessed from volumetric and strain indices (Fig. 6) Figure (6) The 3 phasic functions of LA as assessed by volumetric and strain indices Echocardiographic Assessment of Mitral Stenosis All patients underwent comprehensive evaluation of mitral stenosis severity at baseline and follow-up according to current guideline recommendations. Transthoracic echocardiography (TTE) was performed using commercially available ultrasound systems with patients in the left lateral decubitus position. Standard parasternal long- and short-axis, apical two-, three-, and four-chamber views were acquired. Mitral valve area (MVA) was primarily assessed by direct planimetry in the parasternal short-axis view at the level of the leaflet tips during mid-diastole, ensuring optimal image quality and avoidance of oblique cuts. Pressure half-time (PHT)–derived MVA was calculated when appropriate but was not used as the primary measure, particularly in the post-BMV setting, due to its known limitations following changes in left atrial and left ventricular compliance. Transmitral inflow velocities were obtained using pulsed-wave Doppler from the apical four-chamber view, with the sample volume positioned at the tips of the mitral leaflets. Continuous-wave Doppler was used to record the highest transmitral velocities, and the mean diastolic transmitral gradient (MG) was calculated by tracing the diastolic velocity–time integral. All Doppler measurements were averaged over three consecutive cardiac cycles in patients in sinus rhythm. Mitral regurgitation severity was assessed using an integrative approach incorporating color Doppler jet characteristics, vena contracta width, and spectral Doppler findings, in accordance with guideline recommendations. Right ventricular systolic pressure was estimated from the peak tricuspid regurgitation velocity using the modified Bernoulli equation, with right atrial pressure estimated from inferior vena cava size and collapsibility. Statistical Analysis Statistical analyses were performed using SPSS software (version 28.0; IBM Corp., Armonk, NY). Continuous variables were tested for normality using the Kolmogorov–Smirnov and Shapiro–Wilk tests and were found to be non-normally distributed. Accordingly, continuous data are presented as median with interquartile range (IQR), and categorical variables are expressed as frequencies and percentages. Comparisons between patients with mitral stenosis and healthy controls were performed using the Mann–Whitney U test. Paired comparisons within the patient group before and after balloon mitral valvuloplasty were conducted using the Wilcoxon signed-rank test. The strength and direction of associations between continuous variables were assessed using Spearman rank correlation analysis, with correlation coefficients reported as Spearman’s rho (ρ). All statistical tests were two-sided, and a p-value < 0.05 was considered statistically significant. Results We screened 68 consecutive patients, nineteen patients were excluded for various reasons as mentioned in Figure (7). Our final cohort was 49 patients for whom CMR study was done at baseline (pre BMV) and after mid-long term follow up (9-12 months). CMR was also done for thirty age and sex matched healthy volunteers as a control group. We categorized patients and controls into 3 groups; Group A (Pre BMV), Group B (Post BMV) and Group C (Controls) Baseline Characteristics Baseline characteristics are shown in table (1). The median age of the MS patients was 31 years with a marked female predominance (84%). Most patients were highly symptomatic at presentation, with about 70% of patients in NYHA class III (Median NYHA class =3) and a median symptom duration of 12 months. Baseline demographics and hemodynamic parameters were comparable to healthy controls. Table 1. Baseline Clinical Characteristics of Study Patients Parameter MS patients Control group p-value Age (years) 31 (+/-9.5) 30 (+/-8) 0.40 Male sex, n (%) 8 (16) 10 (33.3) 0.08 Female sex, n (%) 41 (84) 20 (66.7) — Median NYHA class 3 — — Duration of symptoms (months) 12 (18) — — Previous thromboembolism, n (%) 4 (8.2) 0 — Previous BMV, n (%) 6 (12.2) 0 — Diabetes mellitus, n (%) 0 0 — Hypertension, n (%) 0 0 — BSA (m²) 1.7 (0.2) 1.7 (0.2) 0.21 SBP (mmHg) 116 (13.5) 115 (9.4) 0.80 DBP (mmHg) 75 (16) 70 (9) 0.19 HR (beats/min) 74 (21) 72 (18) 0.82 Values are expressed as median (interquartile range). Abbreviations: BMV, balloon mitral valvuloplasty; BSA, body surface area; DBP, diastolic blood pressure; HR, heart rate; NYHA, New York Heart Association; MS, mitral stenosis; SBP, systolic blood pressure. Procedural Results and Hemodynamic Effect of Balloon Mitral Valvuloplasty Most patients reported significant functional improvement following balloon mitral valvuloplasty, with the median NYHA class improving from 3 to 1 at follow-up. Balloon mitral valvuloplasty resulted in a marked and immediate improvement in mitral valve hemodynamics. Mitral valve area increased from a median of 0.9 cm² to 1.8 cm² (p<0.001), accompanied by a significant reduction in mean transmitral gradient from 13 mmHg to 5 mmHg (p<0.001). Peak transmitral gradient decreased from 22 mmHg to 11 mmHg (p<0.001). The left ventricular ejection fraction remained unchanged (65% vs. 66%). There was a trend toward lower pulmonary artery systolic pressure (from 45 mmHg to 40 mmHg, p= 0.08) in the immediate postoperative echocardiogram. (Table 2) Table 2 . Baseline Routine Echocardiographic Data of MS Patients Parameter Pre-BMV Immediately post-BMV p-value Mitral valve area by planimetry (cm²) 0.9 (0.2) 1.8 (0.3) <0.001 Peak transmitral gradient (mmHg) 22 (11.8) 11 (8) <0.001 Mean transmitral gradient (mmHg) 13 (6.5) 5 (4.1) <0.001 Left ventricular ejection fraction (%) 65 (7) 66 (8) 0.97 Estimated PASP (mmHg) 45 (20) 40 (16) 0.08 Values are expressed as median (interquartile range). Abbreviations: BMV, balloon mitral valvuloplasty; PASP, pulmonary artery systolic pressure. Left Atrial Volumetric Remodeling At baseline, cardiac magnetic resonance imaging demonstrated marked left atrial structural and functional remodeling in patients with mitral stenosis compared with healthy controls (table 3). All indexed left atrial volumes were significantly increased, reflecting chronic pressure overload with impaired atrial emptying. In parallel, left atrial volumetric indices of LA function were globally impaired, with significant reductions in reservoir and pump functions, indicating compromised atrial compliance, abnormal atrial–ventricular coupling, and reduced contractile function. Regarding Conduit function, there was improvement of the passive emptying index ( p <0.001) but the change in conduit volume was not statistically different among both groups. Table 3 . Baseline CMR-derived Left Atrial volumes and Functional indices Parameter MS patients (n=49) Controls (n=30) p-value LA indexed volumes (mL/m²) Vmax 74.5 (29.7) 32.4 (6.3) <0.001 Vmin 55.2 (23.6) 11.8 (4.3) <0.001 Vpre-atrial contraction 68.1 (26.7) 18.2 (4.7) <0.001 LA functional parameters Expansion index (%) 30.7 (17.7) 182.9 (69) <0.001 LA ejection fraction (%) 23.4 (10.2) 64.7 (8.5) <0.001 Passive emptying index (%) 8 (8.4) 46.4 (12.7) <0.001 Conduit volume (mL/m²) 25.6 (10.5) 22.4 (6.8) 0.13 Active emptying index (%) 17.5 (8.6) 36.3 (12.8) <0.001 Values are presented as median (IQR). p-values indicate comparison between MS patients and controls. Abbreviations: MS, mitral stenosis; LA, left atrium; Vmax, maximal LA volume; Vmin, minimal LA volume; Vpre-atrial contraction, LA volume before atrial contraction. Following successful balloon mitral valvuloplasty, there was a significant reduction in left atrial volumes, accompanied by a marked improvement in left atrial volumetric functional indices of reservoir, conduit, and pump function. Despite these improvements, post-procedural volumetric indices did not fully normalize when compared with healthy controls. (Table 4 ) Table 4 . CMR-Derived Left Atrial Indexed Volumes Before and After Balloon Mitral Valvuloplasty Parameter Group A (Pre-BMV) Group B (Post-BMV) Median Difference (A–B) (95% CI) p-value (A vs B) Group C (Controls) p-value (B vs C) LA indexed volumes (mL/m²) V max 74.5 (29.7) 61.9 (19.6) −13.5 <0.001 32.4 (6.3) <0.001 V min 55.2 (23.6) 34.9 (19.9) −21.3 <0.001 11.8 (4.3) <0.001 V pre-A 68.1 (26.7) 50.2 (19.8) −19.2 <0.001 18.2 (4.7) <0.001 Expansion index (%) 30.7 (17.7) 78.7 (44.6) 42.3 <0.001 182.9 (69) <0.001 LA ejection fraction (%) 23.4 (10.2) 44 (14.7) 17.4 <0.001 64.7 (8.5) <0.001 Passive emptying index (%) 8 (8.4) 17.4 (15.3) 11 <0.001 46.4 (12.7) <0.001 Conduit volume (mL/m²) 25.6 (10.5) 24.2 (11.9) -0.1 0.94 22.4 (6.8) 0.47 Active emptying index (%) 17.5 (8.6) 27.6 (15.4) 10.9 <0.001 36.3 (12.8) 0.002 Left Atrial Strain Parameters Deformation analysis using CMR strain imaging demonstrated severe baseline impairment of all left atrial (LA) strain parameters including reservoir, conduit, and active strain in patients with severe mitral stenosis compared to healthy controls. (all p < 0.001 vs. controls). Following successful balloon mitral valvuloplasty (BMV), significant improvements were observed across all LA strain parameters at 9–12 months follow-up (all p < 0.001 vs. pre-BMV). LA reservoir strain improved substantially, reaching levels comparable to healthy controls (p = 0.69), suggesting restoration of atrial compliance and reservoir function. Active (contractile) strain also improved significantly (p = 0.05), reflecting enhanced atrial contribution to ventricular filling post-intervention. (Table 5 and Figure 8) In contrast, despite improvement of conduit strain and SR after BMV, both remained significantly lower than in controls (both p < 0.001), indicating the incomplete recovery of LA conduit function despite effective relief of mitral stenosis. Table 5 . Left Atrial Strain and Strain Rates Across the Three Groups Parameter Group A Pre-BMV Group B Post-BMV Median difference (95% CI) p-value (A vs B) Controls P-value (B vs C) Reservoir strain (%) 10.4 (7.8) 18.1 (8.2) 6.23 <0.001 18 (9.1) 0.69 SRs (s⁻¹) 49.2 (36.2) 70.7 (36.5) 23 <0.001 75.2 (26.4) 0.68 Passive strain (%) 4.1 (3.4) 7.6 (5.4) 3.7 <0.001 11.9 (5.9) <0.001 SRe (s⁻¹) -24.5 (19.9) -38.4 (29.2) 17.7 <0.001 -94.2 (53.2) <0.001 Active strain (%) 4.7 (4.6) 7.1 (4.9) 2.1 <0.001 8.8 (2) 0.05 SRa (s⁻¹) -39.2 (40.7) -58.3 (56.6) 17.3 0.002 -61.5 (20.1) 0.29 Values are expressed as median (interquartile range). Abbreviations: BMV, balloon mitral valvuloplasty; SR, strain rate; SRs reservoir strain rate; SRe passive strain rate; SRa active strain rate. Correlation analysis At Baseline prior to BMV, a higher mean gradient (MG) across mitral valve in patients with severe MS was associated with higher EPASP (ρ= 0.5, p<0.001), worse passive strain (ρ=-0.4, p= 0.002) and passive SR (ρ=-0.3, p=0.02). Similarly, a smaller MVA by planimetry was associated with worse passive strain (ρ=0.3, p=0.01) and passive SR (ρ=0.4, p=0.005). The correlation between degree of mitral stenosis by both MVA and MG with LA reservoir strain among patients with severe MS was weak and not statistically significant. Following BMV, drop in MG from baseline (Δ MG) was correlated with the decrease in LA indexed V min (ρ=0.3, p= 0.038), improvement in LA expansion index (ρ=-0.4, p=0.003) and improvement in LA EF (ρ=-0.5, p=0.001). However, Δ MG was not significantly correlated with delta changes in LA indexed V max and PreA volumes. Δ MG was also significantly correlated with improvement of LA global strain (ρ=-0.5, p<0.001) and active LA strain (ρ=-0.5, p<0.001). (Figure 9) Discussion Left atrial (LA) function is increasingly recognized as a critical determinant of morbidity in mitral stenosis, as impairment of phasic atrial mechanics predisposes patients to atrial fibrillation and contributes to progressive functional limitation. ( 13 ) ( 14 ) Accurate and reproducible assessment of LA function is therefore essential. Cardiovascular magnetic resonance (CMR) offers important advantages over echocardiography in this setting, providing highly reproducible measurements of atrial volumes and phasic function that are less dependent on acoustic window limitations and geometric assumptions. This is particularly relevant in mitral stenosis, where the left atrium is often markedly enlarged and asymmetric, which may lead to underestimation of LA size and function by two-dimensional echocardiography. ( 15 ) Furthermore, CMR feature-tracking enables robust quantification of atrial strain with high spatial resolution and favourable signal-to-noise characteristics, and is less susceptible to image dropouts and tracking artifacts that commonly limit speckle-tracking echocardiography in dilated atria. ( 11 ) ( 16 ) ( 17 ) To our knowledge, this study is among the first to comprehensively characterize mid-term changes in LA volumetric and deformation parameters using CMR following BMV in rheumatic MS. The concept of reverse LA remodeling following relief of mitral stenosis has been described in prior echocardiographic and CMR studies. ( 7 ) ( 18 ) ( 19 ) Consistent with these reports, we observed significant improvement in all phasic LA volumes, including maximal, pre-atrial contraction, and minimal volumes, following balloon mitral valvuloplasty (BMV). However, despite these favourable changes, LA volumes did not fully normalize compared with healthy controls. This incomplete recovery may reflect chronic atrial remodeling, fibrosis, and underlying atrial myopathy resulting from prolonged pressure overload. In addition, reverse remodeling may evolve over months to years, and the possibility of continued structural improvement beyond the follow-up period cannot be excluded. Notably, the degree of transmitral gradient reduction was more strongly associated with the reduction in LA minimal volume than with other volumetric indices. Prior studies have demonstrated that LA minimal volume is sensitive to elevated left ventricular filling pressures. ( 20 ) ( 21 ) Accordingly, in patients with severe mitral stenosis—who experience a comparable state of chronic atrial pressure overload—effective reduction in atrial afterload following BMV may preferentially translate into a decrease in LA minimal volume, making it a sensitive marker of early hemodynamic improvement. We also observed differential recovery of LA phasic function in response to unloading after BMV. LA reservoir function demonstrated the most pronounced and consistent improvement, with near-complete normalization of reservoir strain. This finding underscores the load-dependent nature of reservoir function, which primarily reflects atrial compliance and the ability of the left atrium to accommodate pulmonary venous return during ventricular systole. In contrast, LA conduit function remained persistently impaired, as evidenced by subnormal passive strain and early diastolic strain rate, despite successful relief of valvular obstruction. Conduit function appears to be influenced by left ventricular relaxation and intrinsic atrial myocardial properties, which may not substantially improve following BMV. ( 22 ) ( 23 ) Active (contractile) LA function also improved after BMV but did not uniformly normalize, indicating only partial recovery of atrial contractile reserve. Rheumatic heart disease is known to involve atrial myocardium directly, ( 24 ) and persistent atrial fibrosis from rheumatic involvement may limit full restoration of contractile performance even after hemodynamic unloading. Consistent with this concept, we found that the degree of transmitral gradient reduction was significantly correlated with improvement in LA reservoir and active strain, highlighting the strong load dependence of these components of atrial function, while conduit function remained relatively independent of gradient reduction. These findings suggest that comprehensive CMR assessment of LA function may provide incremental insights into atrial remodeling and recovery beyond conventional echocardiographic parameters in patients undergoing BMV. Limitations Our study has several limitations. First, the study population was limited to patients with severe rheumatic mitral stenosis, and the findings may not be generalizable to patients with calcific mitral stenosis or other aetiologies. Second, the study design did not include immediate post-procedural CMR assessment or extended long-term follow-up beyond 9–12 months; therefore, early changes and longer-term evolution of left atrial reverse remodeling could not be fully characterized. Third, left atrial size was assessed using two-dimensional biplane area–length measurements rather than three-dimensional volumetric techniques, which may have resulted in underestimation of true atrial volumes. Finally, although CMR-derived atrial strain provides detailed characterization of atrial mechanics, its broader clinical implementation remains limited by cost, availability, and lack of standardization across vendor platforms. Conclusion Successful balloon mitral valvuloplasty is associated with reverse remodeling of the left atrium, with significant improvement in left atrial structural and functional indices at mid-term follow-up. However, left atrial volumes did not fully normalize, suggesting the presence of partially irreversible atrial remodeling related to chronic pressure overload. Among atrial functional components, reservoir function demonstrated the most pronounced recovery, with near-complete normalization after BMV, whereas conduit function remained impaired despite effective gradient reduction. Improvement in transmitral gradient was significantly associated with recovery of reservoir and contractile strain, but not conduit strain, highlighting differential responsiveness of atrial functional components to hemodynamic unloading. Further studies with longer follow-up are warranted to determine the extent and durability of atrial reverse remodeling beyond one year. Abbreviations BMV Balloon Mitral Valvuloplasty BSA Body Surface Area bSSFP Balanced Steady–State Free Precession CI Confidence Interval CMR Cardiac Magnetic Resonance DBP Diastolic Blood Pressure EF Ejection Fraction EPASP Estimated Pulmonary Artery Systolic Pressure FT Feature Tracking HR Heart Rate IQR Interquartile Range LA Left Atrium LAV Left Atrial Volume LV Left Ventricle MG Mean Gradient MR Mitral Regurgitation MS Mitral Stenosis MVA Mitral Valve Area NYHA New York Heart Association PHT Pressure Half–Time SBP Systolic Blood Pressure SR Strain Rate SRa Late Negative Strain Rate (Contractile) SRe Early Negative Strain Rate (Conduit) SRs Positive Strain Rate (Reservoir) TTE Transthoracic Echocardiography Vmax Maximum Volume Vmin Minimum Volume Vpre A–Pre–Atrial Contraction Volume ρ Spearman Correlation Coefficient Declarations Funding This research did not receive any specific grant from funding agencies in the public, commercial, or non-profit sectors. Ethical approval This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Cairo University Consent to participate Written informed consent was obtained from all patients. Consent to publish The authors affirm that human research participants provided informed consent for publication of the images. Author Contribution M.A.M. conceived the study, collected the data, performed data analysis, and drafted the manuscript. S.R. led the cardiac magnetic resonance image acquisition and analysis, provided expert oversight in image interpretation, and contributed substantially to the imaging components of the study. M.G., K.S., A.E., A.H., and A.S. performed the balloon mitral valvuloplasty procedures and contributed to patient management and data acquisition. R.D. performed the statistical analysis and critically reviewed the manuscript. H.Y., H.K., and M.A. supervised the study, contributed to interpretation of the findings, and critically revised the manuscript. All authors reviewed and approved the final manuscript and agree to be accountable for all aspects of the work. Acknowledgement The authors sincerely thank the radiology technologists and administrative staff at Aswan Heart Centre for their assistance with cardiac magnetic resonance imaging of the study subjects. Data Availability Data supporting the findings of this study are available within the paper and its Supplementary Information. References Baumgartner H, Falk V, Bax JJ 2017 ESC/EACTS guidelines for the management of valvular heart disease. Eur Heart J. ;38:2739–2791. 2., Cameli M, Mandoli GE, Mondillo S et al (2017) Left atrium: the last bulwark before overt heart failure. Heart Fail Rev. 2017;22:123–131 Cameli M, Mandoli GE, Mondillo S (2017) Left atrium: the last bulwark before overt heart failure. 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Int J Cardiovasc Imaging 37:999–1007 Rohani A, Kargar S, Fazlinejad A et al (2017) Acute effect of treatment of mitral stenosis on left atrial function. Arch Cardiovasc Imaging 20:42 Russo C, Jin Z, Homma S, Rundek T, Elkind MSV, Sacco RL et al (2012) Left atrial minimum volume and reservoir function as correlates of left ventricular diastolic dysfunction. Circ Cardiovasc Imaging 5:205–213 Ben-Arzi A, Keren G, Topilsky Y et al (2021) Left atrial minimal volume as a marker of diastolic dysfunction and heart failure symptoms. BMC Med Imaging 21:1–10 Vieira MJ, Teixeira R, Gonçalves L, Gersh BJ (2014) Left atrial mechanics: echocardiographic assessment and clinical implications. J Am Soc Echocardiogr 27:463–478 Hoit BD (2023) Left atrial strain and function: pathophysiology and clinical applications. Heart Fail Rev 28:1453–1465 Kuppahally SS, Akoum N, Burgon NS et al (2010) Left atrial fibrosis quantified by delayed-enhancement MRI in rheumatic heart disease. J Am Coll Cardiol 56:130–136 Additional Declarations No competing interests reported. Supplementary Files floatimage12.png Graphical Abstract Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 22 Apr, 2026 Editor assigned by journal 21 Apr, 2026 Submission checks completed at journal 21 Apr, 2026 First submitted to journal 19 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9465249","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":633778001,"identity":"9ee61f17-5af9-47d3-a083-4343b799dd3a","order_by":0,"name":"Mary Atef Mishriky","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+klEQVRIiWNgGAWjYDAD9mbmgw8SKhgYDIjUYMDAc5wt2eDDGZK0nOcxk5zZRoQW3fazzyQYav7I8TDzmEnzzjssb87efIDhR8U2nFrMzqSbSTAcMzDmYWYrtubddthwZ8+xBMaeM7dxazmQxibBwGaQuJ+ZeeNtoBbGDTdyDJgZ2/BoOf8MqOWfQX0PM4OBNO+cw/aEtdwA2sLYZpDAw8xiJDmz4XAiEVqeMVsw9hkb9jCDAvlYevKGM8cSDuL1y/k0xhsM3+TkefgPA6Oyxtp2w/Hmgw9+VODWAgQs0n8QnGYweQCfeiBg/oDEqSOgeBSMglEwCkYiAABqU1aEbMMtawAAAABJRU5ErkJggg==","orcid":"","institution":"Cairo University","correspondingAuthor":true,"prefix":"","firstName":"Mary","middleName":"Atef","lastName":"Mishriky","suffix":""},{"id":633778002,"identity":"2483bf34-c0af-4c15-a2c1-502bde1aa1c4","order_by":1,"name":"Soha Romeih","email":"","orcid":"","institution":"Magdi Yacoub Heart Foundation","correspondingAuthor":false,"prefix":"","firstName":"Soha","middleName":"","lastName":"Romeih","suffix":""},{"id":633778003,"identity":"46c1e9f9-b79c-4e93-8224-ea0fe8b49683","order_by":2,"name":"Michael Gergis","email":"","orcid":"","institution":"Magdi Yacoub Heart Foundation","correspondingAuthor":false,"prefix":"","firstName":"Michael","middleName":"","lastName":"Gergis","suffix":""},{"id":633778004,"identity":"789870b4-e788-4a42-bebe-6ee16bd9daeb","order_by":3,"name":"Kerolos Shaker","email":"","orcid":"","institution":"Magdi Yacoub Heart Foundation","correspondingAuthor":false,"prefix":"","firstName":"Kerolos","middleName":"","lastName":"Shaker","suffix":""},{"id":633778005,"identity":"12a5e451-f491-4d5a-9b4a-67165e02594a","order_by":4,"name":"Ahmed Elborae","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Ahmed","middleName":"","lastName":"Elborae","suffix":""},{"id":633778006,"identity":"83485c09-7ea0-48c1-8eaf-68275985f0ed","order_by":5,"name":"Ahmed Hassan","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Ahmed","middleName":"","lastName":"Hassan","suffix":""},{"id":633778007,"identity":"d7d86345-37d3-42bb-9549-c2f0f788c7ff","order_by":6,"name":"Amir Samaan","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Amir","middleName":"","lastName":"Samaan","suffix":""},{"id":633778008,"identity":"06978673-9210-48bb-8eff-a1229208a821","order_by":7,"name":"Ramy Doss","email":"","orcid":"","institution":"Nazareth Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ramy","middleName":"","lastName":"Doss","suffix":""},{"id":633778009,"identity":"e171392b-5956-4944-bc35-9dbe76cf2fa5","order_by":8,"name":"Hesham Yehia","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Hesham","middleName":"","lastName":"Yehia","suffix":""},{"id":633778010,"identity":"20641430-5ff6-4352-81df-ce24d217a9bc","order_by":9,"name":"Hossam Kandil","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Hossam","middleName":"","lastName":"Kandil","suffix":""},{"id":633778011,"identity":"5e4d0aac-1b45-4dd1-8ef8-83c1a53ecfc9","order_by":10,"name":"Magdy Abdelhamid","email":"","orcid":"","institution":"Cairo University","correspondingAuthor":false,"prefix":"","firstName":"Magdy","middleName":"","lastName":"Abdelhamid","suffix":""}],"badges":[],"createdAt":"2026-04-20 00:38:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9465249/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9465249/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108734018,"identity":"abd84020-8565-48ec-969c-28a3fdb2e457","added_by":"auto","created_at":"2026-05-07 19:47:50","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":615089,"visible":true,"origin":"","legend":"\u003cp\u003eLA tracing in 4 and 2 chamber views. LA length is taken as the shorter long axis length (From atrial surface to midpoint of mitral annular plane). Control subject no. 4\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/8b8539cdaf5644dce90ca832.png"},{"id":108806698,"identity":"796ad7d0-4a83-41ab-ada5-937dd09b11e4","added_by":"auto","created_at":"2026-05-08 15:29:17","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":527769,"visible":true,"origin":"","legend":"\u003cp\u003eLeft atrial tracking in the 4-chamber view in a patient with severe rheumatic mitral stenosis (Study Patient no. 22)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/6948b747761602af93c6af4e.png"},{"id":108734021,"identity":"eb94b984-4180-4998-97fc-1b9221e133d8","added_by":"auto","created_at":"2026-05-07 19:47:50","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":402786,"visible":true,"origin":"","legend":"\u003cp\u003eCMR LA Feature tracking. The figure shows a representative example of LA tracking in the 4 chamber view in control subject no. 4\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/95914dac1630a6dac435737f.png"},{"id":108807055,"identity":"37a5df5c-5091-4916-9e71-b14040b4d829","added_by":"auto","created_at":"2026-05-08 15:30:01","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":328521,"visible":true,"origin":"","legend":"\u003cp\u003eStrain curves for the six segments of LA (Left). Average strain curve for all segments (Right). Control subject no. 4\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/e5bf5b072a4146dbbe7c817b.png"},{"id":108807084,"identity":"f96a06fc-5387-4a95-a7ab-814d08074821","added_by":"auto","created_at":"2026-05-08 15:30:06","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":134690,"visible":true,"origin":"","legend":"\u003cp\u003eLA strain and strain rate profiles (Control subject no. 4)\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/0a6972557d777f26e478b997.png"},{"id":108734024,"identity":"61b1d90a-9fa3-440a-9f04-734bfdc19b93","added_by":"auto","created_at":"2026-05-07 19:47:50","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":179247,"visible":true,"origin":"","legend":"\u003cp\u003eThe 3 phasic functions of LA as assessed by volumetric and strain indices\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/b0106fa6236f94b959f86785.png"},{"id":108806059,"identity":"501c76ee-00de-4b4d-91f7-8b84d7777421","added_by":"auto","created_at":"2026-05-08 15:27:35","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":101019,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart for derivation of the study population cohort\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/c85320a0475d1d2aaf08fa7c.png"},{"id":108806239,"identity":"fe259e17-b1d3-4fbe-80de-683bd2741886","added_by":"auto","created_at":"2026-05-08 15:28:07","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":117329,"visible":true,"origin":"","legend":"\u003cp\u003eLA strain and SR curves before BMV (Left) and after BMV (Right) in study pt no. (10)\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/747fc5946c7c67da34dedc70.png"},{"id":108734026,"identity":"723ddcf6-3a38-43ea-87a0-124f0b45de3b","added_by":"auto","created_at":"2026-05-07 19:47:50","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":73138,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between delta mean gradient and delta total (reservoir) strain (Left) and active strain (right)\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/600569651581b1d8e44e539e.png"},{"id":109067520,"identity":"50a3d698-5f39-4ab9-b0c0-9d58cebaf7bf","added_by":"auto","created_at":"2026-05-12 09:55:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2984240,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/9c55289c-dc03-4109-8066-ced27c1200db.pdf"},{"id":108806561,"identity":"c0089600-ba9e-4212-b073-018d6ad77904","added_by":"auto","created_at":"2026-05-08 15:28:55","extension":"png","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":263684,"visible":true,"origin":"","legend":"\u003cp\u003eGraphical Abstract\u003c/p\u003e","description":"","filename":"floatimage12.png","url":"https://assets-eu.researchsquare.com/files/rs-9465249/v1/df2f6112e31321967dc0dc6c.png"}],"financialInterests":"No competing interests reported.","formattedTitle":"Reverse Left Atrial Remodeling After Balloon Mitral Valvuloplasty in Severe Rheumatic Mitral Stenosis: A Cardiac Magnetic Resonance Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMitral stenosis (MS), most commonly of rheumatic etiology, is characterized by chronic obstruction to left ventricular inflow, leading to sustained elevation of left atrial (LA) pressure and progressive impairment of atrial structure and function.\u003csup\u003e(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/sup\u003e Long-standing pressure overload results in LA dilatation, wall fibrosis, reduced compliance, and deterioration of phasic atrial functions, including reservoir, conduit, and contractile components.\u003csup\u003e(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e These changes are closely linked to adverse clinical outcomes such as atrial fibrillation, thromboembolic events, and heart failure, making assessment of LA remodeling an important marker of disease severity and clinical risk in MS.\u003csup\u003e(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eBalloon mitral valvuloplasty (BMV) is the treatment of choice for patients with symptomatic severe rheumatic mitral stenosis (MS) and favorable valve morphology, providing immediate relief of transmitral obstruction and reduction of left atrial (LA) pressure.\u003csup\u003e(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/sup\u003e Previous studies have demonstrated reductions in LA dimensions and volumes following successful BMV, predominantly using two-dimensional and three-dimensional echocardiography, with most investigations limited to immediate or short-term follow-up. \u003csup\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/sup\u003e However, LA volumetric parameters are highly load dependent and may not fully capture intrinsic myocardial recovery, particularly in the mid- to long-term period after intervention.\u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eCardiovascular magnetic resonance (CMR) is considered the gold standard for the assessment of cardiac chamber volumes due to its high spatial resolution and excellent reproducibility, allowing accurate quantification of LA size and remodeling.\u003csup\u003e(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e Furthermore, CMR feature tracking (FT) applied to routine cine images enables comprehensive evaluation of LA phasic deformation, providing load-independent insights into atrial myocardial function.\u003csup\u003e(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/sup\u003e Despite its potential advantages, data on CMR-derived LA volumetric and deformation changes following BMV remain limited. The aim of this study was to assess mid-term changes in left atrial structure and phasic function following successful balloon mitral valvuloplasty using CMR-derived volumetric and deformation parameters, and to compare these findings with healthy controls. Secondary objectives included evaluating the relationship between mitral stenosis severity and LA functional indices.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Population\u003c/h2\u003e \u003cp\u003eThis observational cohort study was conducted at Aswan Heart Centre, a tertiary care referral center in Upper Egypt. Between December 2017 and December 2022, 68 consecutive patients with symptomatic severe rheumatic mitral stenosis were screened for inclusion. In addition, 30 age- and sex-matched healthy individuals without known cardiovascular disease were prospectively recruited as a control group.\u003c/p\u003e \u003cp\u003ePatients were eligible for inclusion if they had symptomatic rheumatic mitral stenosis in sinus rhythm, a mitral valve area (MVA)\u0026thinsp;\u0026lt;\u0026thinsp;1.5 cm\u0026sup2;, and favorable valve morphology based on standard echocardiographic scoring systems, and subsequently underwent balloon mitral valvuloplasty (BMV). Successful BMV was defined as achievement of a post-procedural MVA\u0026thinsp;\u0026ge;\u0026thinsp;1.5 cm\u0026sup2; in the absence of more than mild mitral regurgitation.\u003c/p\u003e \u003cp\u003eExclusion criteria included inadequate post-procedural valve dilation (MVA\u0026thinsp;\u0026lt;\u0026thinsp;1.5 cm\u0026sup2;), development of moderate or severe mitral regurgitation, atrial fibrillation at baseline or during follow-up, prior cardiac surgery, uncontrolled systemic hypertension, advanced systemic disease, or any condition known to independently affect left atrial function.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eImaging Protocol\u003c/h3\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eCMR Protocol\u003c/h2\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003eImage Acquisition\u003c/h2\u003e \u003cp\u003eCardiovascular magnetic resonance imaging was performed using a 1.5-T scanner (Magnetom Aera, Siemens Medical Systems, Erlangen, Germany) with retrospective electrocardiographic gating. All images were acquired during breath-holding using balanced steady-state free precession (bSSFP) sequences.\u003c/p\u003e \u003cp\u003eStandard cine images were obtained in vertical long-axis two- and four-chamber views and in contiguous short-axis planes covering both ventricles from the base to the apex (12\u0026ndash;14 slices).Typical imaging parameters included a flip angle of 50\u0026ndash;70\u0026deg;, slice thickness of 6\u0026ndash;8 mm with no interslice gap, matrix size of 160 \u0026times; 256, field of view of 350\u0026ndash;400 mm, repetition time of 3.2\u0026ndash;3.8 ms, echo time of 1.6\u0026ndash;1.9 ms, and a temporal resolution of approximately 25 ms.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e\n\u003ch3\u003eCMR Image Analysis\u003c/h3\u003e\n\u003cp\u003eAll CMR datasets were analyzed using dedicated post-processing software by experienced observers blinded to clinical and echocardiographic data.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eLeft Atrial Volumetric Analysis\u003c/h2\u003e \u003cp\u003eLeft atrial (LA) volumes were quantified using the biplane area\u0026ndash;length method from two- and four-chamber cine images. (Figs.\u0026nbsp;1 and 2). Semi-automated tracing of the LA endocardial borders was performed at different phases of the cardiac cycle, including the left atrial appendage while excluding pulmonary veins.\u003c/p\u003e \u003cp\u003eLA volume was calculated using the formula:\u003c/p\u003e \u003cp\u003e \u003cb\u003eLA volume (mL)\u0026thinsp;=\u0026thinsp;0.85 \u0026times; A2C \u0026times; A4C / L\u003c/b\u003e,\u003csup\u003e(12)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003ewhere A2C and A4C represent the LA areas in the two- and four-chamber views, respectively, and L is the shorter long-axis LA length measured from the atrial roof to the midpoint of the mitral annulus.\u003csup\u003e(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eLA volumes were measured at:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eMaximum LA volume (LA Vmax)\u003c/b\u003e: at left ventricular end-systole\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003ePre-atrial contraction volume (LA Vpre-A)\u003c/b\u003e: at late LV diastole immediately before atrial contraction\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eMinimum LA volume (LA Vmin)\u003c/b\u003e: at LV end-diastole following atrial contraction\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eAll volumes were indexed to BSA. LA size assessment was therefore based on two-dimensional measurements rather than three-dimensional volumetric acquisition, a limitation acknowledged in the interpretation of results.\u003c/p\u003e \u003cp\u003eVolumetric indices of LA phasic function were calculated as follows:\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003e• Total (reservoir) emptying fraction:\u003c/h3\u003e\n\u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e(LAVmax\u0026thinsp;\u0026minus;\u0026thinsp;LAVmin) / LAVmax \u0026times; 100\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e\n\u003ch3\u003e• Passive (conduit) emptying fraction:\u003c/h3\u003e\n\u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e(LAVmax\u0026thinsp;\u0026minus;\u0026thinsp;LAVpre-A) / LAVmax \u0026times; 100\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e\u0026bull; Active (booster pump) emptying fraction:\u003c/h2\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e(LAVpre-A\u0026thinsp;\u0026minus;\u0026thinsp;LAVmin) / LAVpre-A \u0026times; 100\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(1)\u003c/strong\u003e \u003cp\u003eLA tracing in 4 and 2 chamber views. LA length is taken as the shorter long axis length (From atrial surface to midpoint of mitral annular plane). Control subject no. 4\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(2)\u003c/strong\u003e \u003cp\u003eLeft atrial tracking in the 4-chamber view in a patient with severe rheumatic mitral stenosis (Study Patient no. 22)\u003c/p\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eLeft Atrial Feature-Tracking Analysis\u003c/h2\u003e \u003cp\u003eLA strain and strain-rate parameters were derived from bSSFP cine images using feature-tracking software (MASS MR Analytical Software System, version 2021-EXP, Leiden University Medical Center, the Netherlands). Images were exported in DICOM format for offline analysis.\u003c/p\u003e \u003cp\u003eLA endocardial borders were manually delineated on two- and four-chamber cine images at LV end-systole and end-diastole. Manual adjustments were performed when necessary to ensure optimal tracking and to exclude pulmonary veins. Following application of the automated tracking algorithm, contours were propagated throughout the cardiac cycle. (Fig.\u0026nbsp;3). Tracking quality was visually inspected on a segmental basis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(3)\u003c/strong\u003e \u003cp\u003eCMR LA Feature tracking. The figure shows a representative example of LA tracking in the 4 chamber view in control subject no. 4\u003c/p\u003e \u003c/p\u003e \u003cp\u003eGlobal LA deformation parameters were calculated by averaging values from six atrial segments. (Figs.\u0026nbsp;4, 5). The following strain components were analyzed:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eReservoir strain (εR)\u003c/b\u003e: reflecting LA reservoir function during ventricular systole\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eConduit strain (εCD)\u003c/b\u003e: reflecting passive LA emptying during early ventricular diastole\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eContractile strain (εCT)\u003c/b\u003e: reflecting active LA booster pump function during late ventricular diastole\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eCorresponding strain-rate parameters included:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSRs\u003c/b\u003e: peak positive strain rate (reservoir function)\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSRe\u003c/b\u003e: peak early negative strain rate (conduit function)\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSRa\u003c/b\u003e: peak late negative strain rate (contractile function)\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(4)\u003c/strong\u003e \u003cp\u003eStrain curves for the six segments of LA (Left). Average strain curve for all segments (Right). Control subject no. 4\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(5)\u003c/strong\u003e \u003cp\u003eLA strain and strain rate profiles (Control subject no. 4)\u003c/p\u003e \u003c/p\u003e \u003cp\u003eLA functions were assessed from volumetric and strain indices (Fig.\u0026nbsp;6)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;(6)\u003c/strong\u003e \u003cp\u003eThe 3 phasic functions of LA as assessed by volumetric and strain indices\u003c/p\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eEchocardiographic Assessment of Mitral Stenosis\u003c/h2\u003e \u003cp\u003e All patients underwent comprehensive evaluation of mitral stenosis severity at baseline and follow-up according to current guideline recommendations. Transthoracic echocardiography (TTE) was performed using commercially available ultrasound systems with patients in the left lateral decubitus position. Standard parasternal long- and short-axis, apical two-, three-, and four-chamber views were acquired.\u003c/p\u003e \u003cp\u003eMitral valve area (MVA) was primarily assessed by direct planimetry in the parasternal short-axis view at the level of the leaflet tips during mid-diastole, ensuring optimal image quality and avoidance of oblique cuts. Pressure half-time (PHT)\u0026ndash;derived MVA was calculated when appropriate but was not used as the primary measure, particularly in the post-BMV setting, due to its known limitations following changes in left atrial and left ventricular compliance.\u003c/p\u003e \u003cp\u003eTransmitral inflow velocities were obtained using pulsed-wave Doppler from the apical four-chamber view, with the sample volume positioned at the tips of the mitral leaflets. Continuous-wave Doppler was used to record the highest transmitral velocities, and the mean diastolic transmitral gradient (MG) was calculated by tracing the diastolic velocity\u0026ndash;time integral. All Doppler measurements were averaged over three consecutive cardiac cycles in patients in sinus rhythm.\u003c/p\u003e \u003cp\u003e Mitral regurgitation severity was assessed using an integrative approach incorporating color Doppler jet characteristics, vena contracta width, and spectral Doppler findings, in accordance with guideline recommendations. Right ventricular systolic pressure was estimated from the peak tricuspid regurgitation velocity using the modified Bernoulli equation, with right atrial pressure estimated from inferior vena cava size and collapsibility.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eStatistical analyses were performed using SPSS software (version 28.0; IBM Corp., Armonk, NY). Continuous variables were tested for normality using the Kolmogorov\u0026ndash;Smirnov and Shapiro\u0026ndash;Wilk tests and were found to be non-normally distributed. Accordingly, continuous data are presented as median with interquartile range (IQR), and categorical variables are expressed as frequencies and percentages.\u003c/p\u003e \u003cp\u003eComparisons between patients with mitral stenosis and healthy controls were performed using the Mann\u0026ndash;Whitney U test. Paired comparisons within the patient group before and after balloon mitral valvuloplasty were conducted using the Wilcoxon signed-rank test. The strength and direction of associations between continuous variables were assessed using Spearman rank correlation analysis, with correlation coefficients reported as Spearman\u0026rsquo;s rho (ρ).\u003c/p\u003e \u003cp\u003eAll statistical tests were two-sided, and a p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eWe screened 68 consecutive patients, nineteen patients were excluded for various reasons as mentioned in Figure (7). Our final cohort was 49 patients for whom CMR study was done at baseline (pre BMV) and after mid-long term follow up (9-12 months). CMR was also done for thirty age and sex matched healthy volunteers as a control group. We categorized patients and controls into 3 groups; Group A (Pre BMV), Group B (Post BMV) and Group C (Controls)\u003c/p\u003e\n\u003cp\u003eBaseline Characteristics\u003c/p\u003e\n\u003cp\u003eBaseline characteristics are shown in table (1). The median age of the MS patients was 31 years with a marked female predominance (84%). Most patients were highly symptomatic at presentation, with about 70% of patients in NYHA class III (Median NYHA class =3) and a median symptom duration of 12 months. Baseline demographics and hemodynamic parameters were comparable to healthy controls.\u003c/p\u003e\n\u003cp\u003eTable 1. Baseline Clinical Characteristics of Study Patients\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eParameter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMS patients\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eControl group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e31 (+/-9.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e30 (+/-8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMale sex, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8 (16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e10 (33.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eFemale sex, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e41 (84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e20 (66.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMedian NYHA class\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eDuration of symptoms (months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e12 (18)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePrevious thromboembolism, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 (8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePrevious BMV, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6 (12.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eDiabetes mellitus, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eHypertension, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026mdash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBSA (m\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1.7 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1.7 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSBP (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e116 (13.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e115 (9.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eDBP (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e75 (16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e70 (9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eHR (beats/min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e74 (21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e72 (18)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are expressed as median (interquartile range). Abbreviations: BMV, balloon mitral valvuloplasty; BSA, body surface area; DBP, diastolic blood pressure; HR, heart rate; NYHA, New York Heart Association; MS, mitral stenosis; SBP, systolic blood pressure.\u003c/p\u003e\n\u003cp\u003eProcedural Results and Hemodynamic Effect of Balloon Mitral Valvuloplasty\u003c/p\u003e\n\u003cp\u003eMost patients reported significant functional improvement following balloon mitral valvuloplasty, with the median NYHA class improving from 3 to 1 at follow-up. \u0026nbsp;Balloon mitral valvuloplasty resulted in a marked and immediate improvement in mitral valve hemodynamics. Mitral valve area increased from a median of 0.9 cm\u0026sup2; to 1.8 cm\u0026sup2; (p\u0026lt;0.001), accompanied by a significant reduction in mean transmitral gradient from 13 mmHg to 5 mmHg (p\u0026lt;0.001). Peak transmitral gradient decreased from 22 mmHg to 11 mmHg (p\u0026lt;0.001). The left ventricular ejection fraction remained unchanged (65% vs. 66%). There was a trend toward lower pulmonary artery systolic pressure (from 45 mmHg to 40 mmHg, p= 0.08) in the immediate postoperative echocardiogram. \u0026nbsp;(Table 2)\u003c/p\u003e\n\u003cp\u003eTable 2 \u0026nbsp;. Baseline Routine Echocardiographic Data of MS Patients\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eParameter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePre-BMV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eImmediately post-BMV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMitral valve area by planimetry (cm\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.9 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1.8 (0.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePeak transmitral gradient (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e22 (11.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e11 (8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMean transmitral gradient (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e13 (6.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5 (4.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLeft ventricular ejection fraction (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e65 (7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e66 (8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eEstimated PASP (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e45 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e40 (16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are expressed as median (interquartile range). Abbreviations: BMV, balloon mitral valvuloplasty; PASP, pulmonary artery systolic pressure.\u003c/p\u003e\n\u003cp\u003eLeft Atrial Volumetric Remodeling\u003c/p\u003e\n\u003cp\u003eAt baseline, cardiac magnetic resonance imaging demonstrated marked left atrial structural and functional remodeling in patients with mitral stenosis compared with healthy controls (table 3). All indexed left atrial volumes were significantly increased, reflecting chronic pressure overload with impaired atrial emptying. In parallel, left atrial volumetric indices of LA function \u0026nbsp;were globally impaired, with significant reductions in reservoir \u0026nbsp;and pump functions, indicating compromised atrial compliance, abnormal atrial\u0026ndash;ventricular coupling, and reduced contractile function. Regarding Conduit function, there was improvement of the passive emptying index (\u003cem\u003ep\u003c/em\u003e\u0026lt;0.001) but the change in conduit volume was not statistically different among both groups.\u003c/p\u003e\n\u003cp\u003eTable 3 . Baseline CMR-derived Left Atrial volumes and Functional indices\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMS patients (n=49)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eControls (n=30)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eLA indexed volumes (mL/m\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eVmax\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e74.5 (29.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e32.4 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eVmin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e55.2 (23.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e11.8 (4.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eVpre-atrial contraction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e68.1 (26.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18.2 (4.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eLA functional parameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eExpansion index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e30.7 (17.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e182.9 (69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLA ejection fraction (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e23.4 (10.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e64.7 (8.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePassive emptying index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8 (8.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e46.4 (12.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eConduit volume (mL/m\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e25.6 (10.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e22.4 (6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eActive emptying index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.5 (8.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e36.3 (12.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eValues are presented as median (IQR). p-values indicate comparison between MS patients and controls. Abbreviations: MS, mitral stenosis; LA, left atrium; Vmax, maximal LA volume; Vmin, minimal LA volume; Vpre-atrial contraction, LA volume before atrial contraction.\u003c/p\u003e\n\u003cp\u003eFollowing successful balloon mitral valvuloplasty, there was a significant reduction in left atrial volumes, accompanied by a marked improvement in left atrial volumetric functional indices of reservoir, conduit, and pump function. Despite these improvements, post-procedural volumetric indices did not fully normalize when compared with healthy controls. (Table 4 )\u003c/p\u003e\n\u003cp\u003eTable 4 . CMR-Derived Left Atrial Indexed Volumes Before and After Balloon Mitral Valvuloplasty\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eParameter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGroup A (Pre-BMV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGroup B (Post-BMV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMedian Difference (A\u0026ndash;B) (95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ep-value (A vs B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGroup C (Controls)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ep-value (B vs C)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLA indexed volumes (mL/m\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eV max\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e74.5 (29.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e61.9 (19.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026minus;13.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e32.4 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eV min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e55.2 (23.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e34.9 (19.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026minus;21.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e11.8 (4.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eV pre-A\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e68.1 (26.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e50.2 (19.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026minus;19.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18.2 (4.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eExpansion index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e30.7 (17.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e78.7 (44.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e42.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e182.9 (69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLA ejection fraction (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e23.4 (10.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e44 (14.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e64.7 (8.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePassive emptying index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8 (8.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.4 (15.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e46.4 (12.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eConduit volume (mL/m\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e25.6 (10.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24.2 (11.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e22.4 (6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eActive emptying index (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.5 (8.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e27.6 (15.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e10.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e36.3 (12.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eLeft Atrial Strain Parameters\u003c/p\u003e\n\u003cp\u003eDeformation analysis using CMR strain imaging demonstrated severe baseline impairment of all left atrial (LA) strain parameters including reservoir, conduit, and active strain in patients with severe mitral stenosis compared to healthy controls. (all p \u0026lt; 0.001 vs. controls).\u003c/p\u003e\n\u003cp\u003eFollowing successful balloon mitral valvuloplasty (BMV), significant improvements were observed across all LA strain parameters at 9\u0026ndash;12 months follow-up \u0026nbsp;(all p \u0026lt; 0.001 vs. pre-BMV). LA reservoir strain improved substantially, reaching levels comparable to healthy controls (p = 0.69), suggesting restoration of atrial compliance and reservoir function. Active (contractile) strain also improved significantly (p = 0.05), reflecting enhanced atrial contribution to ventricular filling post-intervention. \u0026nbsp;(Table 5 and Figure 8)\u003c/p\u003e\n\u003cp\u003eIn contrast, despite improvement of conduit strain \u0026nbsp;and SR after BMV, both remained significantly lower than in controls (both p \u0026lt; 0.001), indicating the incomplete recovery of \u0026nbsp;LA conduit function despite effective relief of mitral stenosis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 5 . Left Atrial Strain and Strain Rates Across the Three Groups\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eParameter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGroup A Pre-BMV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGroup B Post-BMV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMedian difference (95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ep-value\u0026nbsp;\u003cbr\u003e\u0026nbsp;(A vs B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eControls\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eP-value\u003cbr\u003e\u0026nbsp; (B vs C)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eReservoir strain (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e10.4 (7.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18.1 (8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18 (9.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSRs (s⁻\u0026sup1;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e49.2 (36.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e70.7 (36.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e75.2 (26.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePassive strain (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.1 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7.6 (5.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e11.9 (5.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSRe (s⁻\u0026sup1;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-24.5 (19.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-38.4 (29.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-94.2 (53.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eActive strain (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4.7 (4.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7.1 (4.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8.8 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSRa (s⁻\u0026sup1;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-39.2 (40.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-58.3 (56.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e17.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e-61.5 (20.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are expressed as median (interquartile range). Abbreviations: \u0026nbsp;BMV, balloon mitral valvuloplasty; \u0026nbsp;SR, strain rate; SRs reservoir strain rate; SRe passive strain rate; SRa active strain rate.\u003c/p\u003e\n\u003cp\u003eCorrelation analysis\u003c/p\u003e\n\u003cp\u003eAt Baseline prior to BMV, a higher mean gradient (MG) across mitral valve in patients with severe MS was associated with higher EPASP (\u0026rho;= 0.5, p\u0026lt;0.001), worse passive strain (\u0026rho;=-0.4, p= 0.002) and passive SR (\u0026rho;=-0.3, p=0.02). Similarly, a smaller MVA by planimetry was associated with worse passive strain (\u0026rho;=0.3, p=0.01) and passive SR (\u0026rho;=0.4, p=0.005). The correlation between degree of mitral stenosis by both MVA and MG with LA reservoir strain among patients with severe MS was weak and not statistically significant. Following BMV, drop in MG from baseline (\u0026Delta; MG) was correlated with the decrease in LA indexed V min (\u0026rho;=0.3, p= 0.038), improvement in LA expansion index (\u0026rho;=-0.4, p=0.003) and improvement in LA EF (\u0026rho;=-0.5, p=0.001). However, \u0026Delta; MG \u0026nbsp;was not significantly correlated with delta changes in LA indexed V max and PreA volumes. \u0026nbsp;\u0026Delta; MG was \u0026nbsp;also significantly correlated with improvement of LA global strain (\u0026rho;=-0.5, p\u0026lt;0.001) and active LA strain (\u0026rho;=-0.5, p\u0026lt;0.001). (Figure 9)\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eLeft atrial (LA) function is increasingly recognized as a critical determinant of morbidity in mitral stenosis, as impairment of phasic atrial mechanics predisposes patients to atrial fibrillation and contributes to progressive functional limitation. \u003csup\u003e(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/sup\u003e Accurate and reproducible assessment of LA function is therefore essential. Cardiovascular magnetic resonance (CMR) offers important advantages over echocardiography in this setting, providing highly reproducible measurements of atrial volumes and phasic function that are less dependent on acoustic window limitations and geometric assumptions. This is particularly relevant in mitral stenosis, where the left atrium is often markedly enlarged and asymmetric, which may lead to underestimation of LA size and function by two-dimensional echocardiography. \u003csup\u003e(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/sup\u003e Furthermore, CMR feature-tracking enables robust quantification of atrial strain with high spatial resolution and favourable signal-to-noise characteristics, and is less susceptible to image dropouts and tracking artifacts that commonly limit speckle-tracking echocardiography in dilated atria.\u003csup\u003e(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e) (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e) (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e)\u003c/sup\u003e To our knowledge, this study is among the first to comprehensively characterize mid-term changes in LA volumetric and deformation parameters using CMR following BMV in rheumatic MS.\u003c/p\u003e \u003cp\u003eThe concept of reverse LA remodeling following relief of mitral stenosis has been described in prior echocardiographic and CMR studies.\u003csup\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e) (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e)\u003c/sup\u003e Consistent with these reports, we observed significant improvement in all phasic LA volumes, including maximal, pre-atrial contraction, and minimal volumes, following balloon mitral valvuloplasty (BMV). However, despite these favourable changes, LA volumes did not fully normalize compared with healthy controls. This incomplete recovery may reflect chronic atrial remodeling, fibrosis, and underlying atrial myopathy resulting from prolonged pressure overload. In addition, reverse remodeling may evolve over months to years, and the possibility of continued structural improvement beyond the follow-up period cannot be excluded.\u003c/p\u003e \u003cp\u003eNotably, the degree of transmitral gradient reduction was more strongly associated with the reduction in LA minimal volume than with other volumetric indices. Prior studies have demonstrated that LA minimal volume is sensitive to elevated left ventricular filling pressures. \u003csup\u003e(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e) (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e)\u003c/sup\u003e Accordingly, in patients with severe mitral stenosis\u0026mdash;who experience a comparable state of chronic atrial pressure overload\u0026mdash;effective reduction in atrial afterload following BMV may preferentially translate into a decrease in LA minimal volume, making it a sensitive marker of early hemodynamic improvement.\u003c/p\u003e \u003cp\u003eWe also observed differential recovery of LA phasic function in response to unloading after BMV. LA reservoir function demonstrated the most pronounced and consistent improvement, with near-complete normalization of reservoir strain. This finding underscores the load-dependent nature of reservoir function, which primarily reflects atrial compliance and the ability of the left atrium to accommodate pulmonary venous return during ventricular systole. In contrast, LA conduit function remained persistently impaired, as evidenced by subnormal passive strain and early diastolic strain rate, despite successful relief of valvular obstruction. Conduit function appears to be influenced by left ventricular relaxation and intrinsic atrial myocardial properties, which may not substantially improve following BMV. \u003csup\u003e(\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e) (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eActive (contractile) LA function also improved after BMV but did not uniformly normalize, indicating only partial recovery of atrial contractile reserve. Rheumatic heart disease is known to involve atrial myocardium directly,\u003csup\u003e(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e)\u003c/sup\u003e and persistent atrial fibrosis from rheumatic involvement may limit full restoration of contractile performance even after hemodynamic unloading. Consistent with this concept, we found that the degree of transmitral gradient reduction was significantly correlated with improvement in LA reservoir and active strain, highlighting the strong load dependence of these components of atrial function, while conduit function remained relatively independent of gradient reduction.\u003c/p\u003e \u003cp\u003eThese findings suggest that comprehensive CMR assessment of LA function may provide incremental insights into atrial remodeling and recovery beyond conventional echocardiographic parameters in patients undergoing BMV.\u003c/p\u003e \u003cp\u003eLimitations\u003c/p\u003e \u003cp\u003eOur study has several limitations. First, the study population was limited to patients with severe rheumatic mitral stenosis, and the findings may not be generalizable to patients with calcific mitral stenosis or other aetiologies. Second, the study design did not include immediate post-procedural CMR assessment or extended long-term follow-up beyond 9\u0026ndash;12 months; therefore, early changes and longer-term evolution of left atrial reverse remodeling could not be fully characterized. Third, left atrial size was assessed using two-dimensional biplane area\u0026ndash;length measurements rather than three-dimensional volumetric techniques, which may have resulted in underestimation of true atrial volumes. Finally, although CMR-derived atrial strain provides detailed characterization of atrial mechanics, its broader clinical implementation remains limited by cost, availability, and lack of standardization across vendor platforms.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eSuccessful balloon mitral valvuloplasty is associated with reverse remodeling of the left atrium, with significant improvement in left atrial structural and functional indices at mid-term follow-up. However, left atrial volumes did not fully normalize, suggesting the presence of partially irreversible atrial remodeling related to chronic pressure overload. Among atrial functional components, reservoir function demonstrated the most pronounced recovery, with near-complete normalization after BMV, whereas conduit function remained impaired despite effective gradient reduction. Improvement in transmitral gradient was significantly associated with recovery of reservoir and contractile strain, but not conduit strain, highlighting differential responsiveness of atrial functional components to hemodynamic unloading. Further studies with longer follow-up are warranted to determine the extent and durability of atrial reverse remodeling beyond one year.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBMV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBalloon Mitral Valvuloplasty\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBSA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBody Surface Area\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ebSSFP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBalanced Steady\u0026ndash;State Free Precession\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eConfidence Interval\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCMR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eCardiac Magnetic Resonance\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eDBP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eDiastolic Blood Pressure\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eEF\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eEjection Fraction\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eEPASP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eEstimated Pulmonary Artery Systolic Pressure\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eFT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eFeature Tracking\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eHR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eHeart Rate\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eIQR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eInterquartile Range\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLeft Atrium\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLAV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLeft Atrial Volume\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLeft Ventricle\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMG\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMean Gradient\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMitral Regurgitation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMitral Stenosis\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMVA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMitral Valve Area\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eNYHA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eNew York Heart Association\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePHT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePressure Half\u0026ndash;Time\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSBP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSystolic Blood Pressure\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eStrain Rate\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSRa\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLate Negative Strain Rate (Contractile)\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSRe\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eEarly Negative Strain Rate (Conduit)\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSRs\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePositive Strain Rate (Reservoir)\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eTTE\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eTransthoracic Echocardiography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVmax\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMaximum Volume\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVmin\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMinimum Volume\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVpre\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eA\u0026ndash;Pre\u0026ndash;Atrial Contraction Volume\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eρ\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSpearman Correlation Coefficient\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or non-profit sectors.\u003c/p\u003e\n\u003cp\u003eEthical approval\u003c/p\u003e\n\u003cp\u003eThis study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Cairo University\u003c/p\u003e\n\u003cp\u003eConsent to participate\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from all patients.\u003c/p\u003e\n\u003cp\u003eConsent to publish\u003c/p\u003e\n\u003cp\u003eThe authors affirm that human research participants provided informed consent for publication of the images.\u0026nbsp;\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eM.A.M. conceived the study, collected the data, performed data analysis, and drafted the manuscript. S.R. led the cardiac magnetic resonance image acquisition and analysis, provided expert oversight in image interpretation, and contributed substantially to the imaging components of the study. M.G., K.S., A.E., A.H., and A.S. performed the balloon mitral valvuloplasty procedures and contributed to patient management and data acquisition. R.D. performed the statistical analysis and critically reviewed the manuscript. H.Y., H.K., and M.A. supervised the study, contributed to interpretation of the findings, and critically revised the manuscript. All authors reviewed and approved the final manuscript and agree to be accountable for all aspects of the work.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors sincerely thank the radiology technologists and administrative staff at Aswan Heart Centre for their assistance with cardiac magnetic resonance imaging of the study subjects.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData supporting the findings of this study are available within the paper and its Supplementary Information.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBaumgartner H, Falk V, Bax JJ 2017 ESC/EACTS guidelines for the management of valvular heart disease. Eur Heart J. ;38:2739\u0026ndash;2791. 2., Cameli M, Mandoli GE, Mondillo S et al (2017) Left atrium: the last bulwark before overt heart failure. Heart Fail Rev. 2017;22:123\u0026ndash;131\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCameli M, Mandoli GE, Mondillo S (2017) Left atrium: the last bulwark before overt heart failure. Heart Fail Rev 22:123\u0026ndash;131\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBlume GG, McLeod CJ, Barnes ME et al (2011) Left atrial function: physiology, assessment, and clinical implications. Eur J Echocardiogr 12:421\u0026ndash;430\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTsang TS, Abhayaratna WP, Barnes ME et al (2006) Prediction of cardiovascular outcomes with left atrial size: is volume superior to area or diameter? J Am Coll Cardiol 47:1018\u0026ndash;1023\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIung B, Vahanian A (2011) Rheumatic mitral stenosis. Lancet 378:172\u0026ndash;182\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarabello BA (2005) Modern management of mitral stenosis. Circulation 112:432\u0026ndash;437\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVieira MLC, Silva MC, Wagner CR et al (2013) Left atrium reverse remodeling in patients with mitral valve stenosis after percutaneous valvuloplasty: a 2- and 3-dimensional echocardiographic study. Rev Esp Cardiol 66:17\u0026ndash;23\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBitigen A, T\u0026uuml;rkmen M, Karakaya O et al (2006) Early effects of percutaneous mitral valvuloplasty on left atrial mechanical functions. Tohoku J Exp Med 209:285\u0026ndash;289\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHoit BD (2017) Evaluation of left atrial function: current status. J Am Soc Hypertens 11:109\u0026ndash;120\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaceira AM, Cos\u0026iacute;n-Sales J, Roughton M, Prasad SK, Pennell DJ (2010) Reference left atrial dimensions and volumes by steady-state free precession cardiovascular magnetic resonance. J Cardiovasc Magn Reson 12:65\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKowallick JT, Kutty S, Edelmann F et al (2014) Quantification of left atrial strain and strain rate using cardiovascular magnetic resonance myocardial feature tracking: a feasibility study. J Cardiovasc Magn Reson 16:1\u0026ndash;9\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSievers B, Kirchberg S, Addo M, Bakan A, Brandts B, Trappe HJ (2004) Assessment of left atrial volumes in sinus rhythm and atrial fibrillation using the biplane area\u0026ndash;length method and cardiovascular magnetic resonance imaging with TrueFISP. J Cardiovasc Magn Reson 6:855\u0026ndash;863\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStassen J, Butcher SC, Namazi F, Marsan NA, Bax JJ, Delgado V (2022) Left atrial deformation and atrial fibrillation in patients with rheumatic mitral stenosis. J Am Soc Echocardiogr 35:486\u0026ndash;494\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNaji P, Griffin BP, Asfahan F et al (2019) Left atrial remodeling in mitral stenosis: pathophysiologic and clinical implications. J Am Soc Echocardiogr 32:141\u0026ndash;152\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVidula MK, Xu Z, Xu Y et al (2022) Cardiovascular magnetic resonance characterization of rheumatic mitral stenosis: findings from three worldwide endemic zones. J Cardiovasc Magn Reson 24:1\u0026ndash;11\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarhad H, Seidelmann SB, Vigneault D et al (2017) Left atrial structure and function in hypertrophic cardiomyopathy sarcomere mutation carriers with and without left ventricular hypertrophy. J Cardiovasc Magn Reson 19:1\u0026ndash;10\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTo AC, Flamm SD, Marwick TH, Klein AL (2011) Clinical utility of multimodality left atrial imaging: assessment of size, function, and structure. J Cardiovasc Imaging 4:788\u0026ndash;798\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSamaan AA, Hassan A, Hassan M et al (2021) Left atrial structural and functional remodeling following balloon mitral valvuloplasty. Int J Cardiovasc Imaging 37:999\u0026ndash;1007\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRohani A, Kargar S, Fazlinejad A et al (2017) Acute effect of treatment of mitral stenosis on left atrial function. Arch Cardiovasc Imaging 20:42\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRusso C, Jin Z, Homma S, Rundek T, Elkind MSV, Sacco RL et al (2012) Left atrial minimum volume and reservoir function as correlates of left ventricular diastolic dysfunction. Circ Cardiovasc Imaging 5:205\u0026ndash;213\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBen-Arzi A, Keren G, Topilsky Y et al (2021) Left atrial minimal volume as a marker of diastolic dysfunction and heart failure symptoms. BMC Med Imaging 21:1\u0026ndash;10\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVieira MJ, Teixeira R, Gon\u0026ccedil;alves L, Gersh BJ (2014) Left atrial mechanics: echocardiographic assessment and clinical implications. J Am Soc Echocardiogr 27:463\u0026ndash;478\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHoit BD (2023) Left atrial strain and function: pathophysiology and clinical applications. Heart Fail Rev 28:1453\u0026ndash;1465\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKuppahally SS, Akoum N, Burgon NS et al (2010) Left atrial fibrosis quantified by delayed-enhancement MRI in rheumatic heart disease. J Am Coll Cardiol 56:130\u0026ndash;136\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"the-egyptian-heart-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tehj","sideBox":"Learn more about [The Egyptian Heart Journal](https://tehj.springeropen.com)","snPcode":"43044","submissionUrl":"https://submission.springernature.com/new-submission/43044/3","title":"The Egyptian Heart Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-9465249/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9465249/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eRheumatic mitral stenosis (MS) leads to chronic left atrial (LA) pressure overload, resulting in atrial enlargement and progressive impairment of reservoir, conduit, and contractile function. Although balloon mitral valvuloplasty (BMV) effectively relieves valvular obstruction, the extent of subsequent LA reverse remodeling remains incompletely defined. We aimed to evaluate changes in LA structure and phasic function after successful BMV using cardiac magnetic resonance (CMR).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eForty-nine patients with isolated severe rheumatic MS underwent CMR before and 9\u0026ndash;12 months after successful BMV, defined as a post-procedural mitral valve area\u0026thinsp;\u0026ge;\u0026thinsp;1.5 cm\u0026sup2; without more than mild mitral regurgitation. Age- and sex-matched healthy individuals served as controls. At baseline, patients demonstrated significant LA enlargement and marked impairment of volumetric and deformation-derived reservoir, conduit, and contractile function compared with controls. Following BMV, indexed LA volumes decreased significantly, with parallel improvement in all phasic functional components. Recovery was most pronounced in LA reservoir and contractile strain indices, which approached normal values. In contrast, LA volumes and volumetric functional parameters remained significantly abnormal relative to controls.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eSuccessful BMV was associated with meaningful but incomplete LA reverse remodeling within the first year after intervention. Functional recovery may precede full structural normalization after relief of chronic atrial pressure overload. CMR assessment of LA remodeling may provide clinically relevant insight into cardiac recovery and longitudinal follow-up after BMV in patients with rheumatic MS.\u003c/p\u003e","manuscriptTitle":"Reverse Left Atrial Remodeling After Balloon Mitral Valvuloplasty in Severe Rheumatic Mitral Stenosis: A Cardiac Magnetic Resonance Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-07 19:47:41","doi":"10.21203/rs.3.rs-9465249/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-04-22T21:59:04+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-21T09:39:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-21T09:38:53+00:00","index":"","fulltext":""},{"type":"submitted","content":"The Egyptian Heart Journal","date":"2026-04-20T00:33:07+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"the-egyptian-heart-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tehj","sideBox":"Learn more about [The Egyptian Heart Journal](https://tehj.springeropen.com)","snPcode":"43044","submissionUrl":"https://submission.springernature.com/new-submission/43044/3","title":"The Egyptian Heart Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"788af473-8c74-4b21-99a2-52e0424a61c1","owner":[],"postedDate":"May 7th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T19:47:42+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-07 19:47:41","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9465249","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9465249","identity":"rs-9465249","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}