Real World Barriers to Diagnostic Cardiac Imaging in Adults with Duchenne Muscular Dystrophy Cardiomyopathy

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Murray, Ailis Pollock, Katie Hewitt, Jennifer O'sullivan, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3991442/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Aims: Cardiomyopathy is universally penetrant in young adults with Duchenne muscular dystrophy (DMD), and is increasingly the preponderant cause of death. We sought to determine the rates of, and reasons for, failed diagnostic cardiac imaging in our DMD multidisciplinary care centre as well as the level of agreement between imaging modalities, in order to guide the optimal strategy for cardiac imaging in these patients. Methods and results: We followed all patients attending a Comprehensive Multidisciplinary Adult DMD clinic over 4 years. All attendees underwent transthoracic echocardiography (TTE) and were offered referral for cardiac MRI (CMR). Age, cardiac medications, left ventricular ejection fraction (LVEF), ambulatory status, airway adjuncts and presence and degree of cardiac fibrosis were recorded. A total of 33 patients enrolled, median age 20, with mean follow-up of 3 years and 3 months. Mean LVEF was 51% at enrollment and 45% at follow-up. Presence of any degree of mitral regurgitation correlated strongly to left ventricular systolic dysfunction. CMR was completed in just 25% of patients, all of whom had extensive midwall fibrosis. Of those in whom CMR failed, 52% were unable to lie flat or position correctly for scanning, predominantly due to muscle contractures. Despite suboptimal TTE imaging in 75%, there was good agreement in LVEF between CMR and TTE. Conclusion: We found a high rate of failure to complete diagnostic cardiac imaging in this group of patients with impaired mobility. Our study highlights the importance of multimodality imaging, and practical strategies to overcome environmental obstacles to diagnostic imaging, to better guide aggressiveness of treatment for DMD and its inherent cardiomyopathy. Figures Figure 1 Figure 2 Figure 3 Background Duchenne muscular dystrophy (DMD) is an X-linked recessive disease caused by mutations in the gene encoding dystrophin 1 , a protein essential to the integrity of the cytoskeleton of striated muscle. The complete absence of dystrophin seen in DMD 2 , and resultant progressive atrophy, manifests clinically as gait disturbance with subsequent loss of ambulation, and ultimately cardiac and respiratory failure 3 . Its prevalence is approximately 4.78 per 100,000 males 4 . The natural history of DMD carries a poor prognosis, with death at a mean age of 14.4 years reported in some studies 5 . The introduction of non-invasive ventilation has increased this by approximately 10 years, however. Consequently, cardiomyopathy, which is universally apparent over 18 years of age, has become the leading cause of mortality 6 . Monitoring for pre-clinical evidence of cardiomyopathy presents a challenge in this unique cohort of patients. Contractures, chest wall deformities, ventilation abnormalities and scoliosis are some of the barriers to diagnostic quality imaging of patients with DMD which have been alluded to in previous studies 7, 8 .While more recent research has highlighted the utility of CMR in the evaluation of patients with muscular dystrophy for the presence of preclinical cardiomyopathy 9, 10 , there is a lack of data regarding the extent to which these issues impact on the quality and practicability of cardiac imaging in this group of patients. Aim The aim of this study was to evaluate the optimal strategy for cardiac imaging in young adults with DMD with regard to the practicalities of imaging in individual patients, and to review the extent to which these issues impact on the quality and practicability of cardiac imaging in this group of patients. Methods We conducted a prospective cohort study comparing the diagnostic utility of CMR with TTE in patients with DMD. All patients attending a Comprehensive Multidisciplinary Adult DMD clinic over a 4 year period were enrolled. The clinic provided a single One Stop Visit with an extensive review with Advanced Specialist Care from Pulmonologist, Cardiologist, Neurologist, Physiotherapist, Occupational Therapist, Nutritionist, and Social Worker. All patients were offered referral for CMR and had a TTE study conducted. Data collection occurred at baseline and at patients’ clinical review. Parameters included were age, TTE derived EF at baseline and follow-up, time to follow-up, ambulatory status, use of respiratory adjuncts, whether CMR was performed and, if so, presence or absence of fibrosis and CMR derived EF. In the case of non-attendance for their investigation, we recorded the reason cited by the patient or caregiver. All data collection, storage and reporting was carried out in accordance with local governance procedures, and national and international data protection regulations. Data were analysed for agreement in LVEF between modalities with results illustrated using a Bland-Altman plot. Differences in non-attendance and non-diagnostic exam rates, and the reason for observed differences between modalities, were reported in a qualitative manner. Ethical approval The study protocol was reviewed and ethically approved by the Beaumont Hospital Clinical Audit & Governance Committee (Institutional Review Board reference number CA2023/133). Results We enrolled a total of 33 patients consecutively, all of whom were male. Baseline characteristics and medication use are shown in Table 1. The median age was 20, standard deviation 4.3 years. The box plot depicts the number of patients broken down by LVEF range on TTE at enrolment and follow-up. Table 2 depicts TTE parameters measured for each patient at follow-up, and initial study. We note that of the 13 patients with any degree of mitral regurgitation (MR), 12 (92%) had LVEF less than 55%. Thus the presence of any degree of MR strongly correlates to LVSD in our study cohort. Absence of MR did not correlate well with presence or absence of LVSD, however. TTE was conducted in all patients. Mean EF was 51% at initial echo and 45% at follow-up. Mean follow-up period was 3 years, 3 months. Although imaging was reported as “suboptimal” or “limited” in 75% of cases, only 9% of studies (N=3) were considered non-diagnostic.Patient positioning / immobility was cited as the reason for suboptimal imaging in most cases. Eight patients (25%) underwent a diagnostic quality CMR. The remainder were offered or attempted the scan but declined to attend or attended and were unable to have a diagnostic quality scan for the reasons given. Results are depicted in table 3. Extensive midwall fibrosis was reported in 100% of studies where IV contrast was administered (N=7). Contrast evaluation was not performed in N=1 due to difficulty obtaining IV access, however T1 mapping was suggestive of midwall fibrosis in this case also. Of those with confirmed fibrosis, 14% (N=1) exhibited normal LVEF. The extent of fibrosis was reported in a semi-quantitative manner, with “significant” or “extensive” fibrosis reported in all 8 cases. Image 1 depicts a flowchart showing the number of patients who underwent CMR, as well as reasons not undertaken. The primary reason for non-completion of CMR was recorded as “patient unable to lie flat” or “could not tolerate” due to contractures in all cases except for 1, where “poor IV access” was cited. One patient requiring continuous non-invasive ventilation when lying recumbent was unable to attempt scanning for this reason also. Difficulties encountered with travel were an obstacle to further imaging described frequently by patients and caregivers in our study cohort, however these difficulties were not cited as the reason for failure to complete a scan in any case. Despite the difficulties encountered with both imaging modalities, it is notable that our study found a high degree of correlation between TTE and CMR derived measurement of LV ejection fraction. We used the Bland-Altman plot to assess for clinically acceptable agreement between modalities rather than calculating a correlation coefficient, given the inherent limitations of correlation as a surrogate for agreement in statistical analysis, as well as the lack of any standardised acceptable limits for agreement in LVEF between modalities. We found that there was a high level of agreement between TTE and CMR, with a mean difference in reported LVEF between modalities of 1.625% (95% CI -9.0 - 5.8). Image 2 depicts the results recorded on the Bland-Altman plot. Discussion Our study shows Real-world data from a consecutive Adult population with Duchenne Muscular Dystrophy that show only a small proportion of patients enrolled had both diagnostic quality TTE (91%) and CMR (25%) performed successfully. Our study is the first to report on the actual barriers to obtaining an evaluable CMR. The array of barriers to successful imaging which were encountered prove problematic in obtaining accurate diagnostic information on LV function as well as potentially useful prognostic information such as strain rate and fibrosis, which may be important in guiding treatment decisions. Current evidence for therapeutic strategies based on imaging parameters As in other forms of heart failure (HF), incident left ventricular (LV) systolic dysfunction in DMD should prompt the introduction of treatment with beta adrenergic blockade, renin-angiotensin activation system inhibition, mineralocorticoid receptor antagonist and sodium-glucose cotransporter 2 inhibitor drugs 11 , and Ivabradine. Established TTE parameters, such as reduction in LV ejection fraction and fractional shortening, are well studied in the seminal clinical trials of these drug classes 12-14 . International bodies therefore recommend treatments based on cut-off values in these parameters. Due to complete penetrance of cardiomyopathy in DMD, however, early intervention with conventional drugs is the currently accepted consensus strategy to prevent or delay the onset of clinical HF. The optimal timing of treatment has yet to be determined, and clinical trials are ongoing to ascertain when these drugs should be initiated before the onset of LV systolic dysfunction 15 . The emergence of tissue Doppler and strain imaging, which correlate well with subsequent development of DMD HF 16 , has already seen a role for these parameters in early detection and instigation of treatment. Similarly, CMR parameters such as late gadolinium enhancement of the LV midwall can provide invaluable early prognostic information about the extent of fibrosis, and predict subsequent deterioration in systolic function. Comparison of modalities: TTE Despite recent advances in cardiac magnetic resonance imaging (CMR) and computed tomography (CCT), transthoracic echocardiography (TTE) remains the most commonly used imaging modality in the investigation of cardiomyopathy and heart failure, and in their follow-up 17 . Although the comparatively low cost is likely to be the principal motivation behind its ongoing use in preference to other modalities 18 , TTE continues to bear certain important advantages over CMR and CCT. The widespread availability of TTE makes it accessible to patients who are too unwell or clinically unstable to undergo other departmental imaging studies. Its portability has unique implications in DMD, where practical issues such as immobility and lack of appropriate transportation can render travel to centres with CCT and CMR capability unfeasible for patients. Moreover, the prevalence of contractures seen in DMD limits entry into the CMR scanner, and this is less problematic with a mobile modality such as TTE. Factors limiting the diagnostic accuracy and utility of TTE are also encountered frequently. Image quality is often suboptimal in this almost-universally non-ambulatory cohort as correct positioning is infrequently achieved. Neuromuscular scoliosis and chest wall deformity present a further barrier to the acquisition of good acoustic windows in many cases. In addition to the factors limiting image acquisition, TTE interpretation is also highly operator dependent. This presents unique challenges in serial follow-up examinations when monitoring patients for deteriorating LV function. Varying degrees of correlation have been reported in studies comparing CMR with TTE. Comparison of modalities: CMR Postmortem histopathological examinations in DMD show a paucity of cardiac myocytes with a distinctive pattern of fibrofatty infiltration with early preponderance for the posterior left ventricular wall 19 . CMR can detect this myocardial fibrosis using gadolinium contrast enhancement. The extent of late gadolinium enhancing myocardium indicates the degree of fibrosis, and strongly correlates with the risk of subsequent deterioration in LVEF. Consequently, it is useful in screening for early myocardial involvement prior to the onset of LV systolic dysfunction. Unfortunately only 25% of our patients were able to have CMR performed due to the inherent patient-based and system-based obstacles described above. CMR strain imaging is also increasingly used, and declining circumferential strain even precedes myocardial fibrosis. These technologies are therefore emerging as pre-clinical predictors of earlier and more severe cardiomyopathy, with greater accuracy than conventional TTE imaging. Thus CMR is likely to become much more widespread as a tool to inform risk stratification in DMD. Research is ongoing to investigate how this may guide the timing and optimisation of pre-clinical intervention in cardiomyopathy. Despite these promising advances, CMR has inherent limitations specific to the DMD population of patients. Its cost and consequent lack of widespread availability means that travel to centres with CMR capability may present an obstacle to patients attending for this investigation, especially with regard to immobility and transport. Neuromuscular contractures resulting in scoliosis and fixed flexion deformity of the hip joints are well described and present a barrier to patients entering the MRI scanner (and precluded scanning in 27% of our study cohort). Additionally, 3% of patients required continuous non-invasive ventilation. These devices are generally incompatible with MRI, and therefore scanning could not be achieved in patients who were fully dependent. The use of a multi-modality approach increases diagnostic yield, with the finding of early and extensive pattern of fibrosis on CMR prompting intensification of treatment prior to deterioration in systolic function. Despite the clinical value of this diagnostic information, obtaining it can be onerous on patients, causing significant disruption to routine as well as discomfort at times. It is noted that patients with DMD and their caregivers cite numerous difficulties in attending appointments, due to considerations around wheelchair-accessible travel arrangements, distance to travel and time constraints. Therefore, as the use of imaging increases, it may necessitate tailoring the use of different modalities to clinical need, with due regard to the patient’s ambulatory state, severity of contractures and dependence on respiratory support, as well as other practical considerations not limited to transportation and the availability of caregiver support. Image Concordance Although image quality was suboptimal in a large proportion of TTE studies, it is noteworthy that there was a high level of agreement in LVEF reported on TTE compared with CMR, which is at odds with some previous studies 20 where more heterogeneity was observed. We found that LVEF agreed to within +/- 5% in 88% of patients who underwent both TTE and CMR. This was deemed to be a very satisfactory level of agreement to guide clinical decision making, and further supports the use of TTE as the first line of diagnostic imaging in patients with significant mobility impairment. Technical considerations Although the technical expertise of radiographers and sonographers is beyond the scope of this article, it is acknowledged that a significant skill set is employed in performing high quality studies on patients with significant mobility impairment. At the time of writing, a literature search for training of cardiac sonographers in imaging patients with disabilities did not yield any relevant published results. Specialist training for operators in the practical considerations of this unique patent cohort may well improve imaging yield. Given the frequent citing by our technicians of difficulty with patient positioning as a major factor in suboptimal TTE image quality, it is postulated that additional resourcing of TTE units with healthcare staff to aid with positioning may help to further optimise acoustic windows. A Single Multidisciplinary Team Clinical Review Patients with DMD are almost entirely non-ambulatory and dependent on wheelchairs for mobility, as well as carers for assistance with transport and personal care. Specialised equipment is required to aid with transportation, as well as various devices for respiratory support which require trained operators to be present. This results in a significant stress for patients as well as high demand on their caregivers when numerous different appointments are necessary. The recent establishment of tertiary referral centres such as ours is done with the intention of honing advanced clinical skill from multi-disciplinary services resulting in a broad range of specialised services being made available to patients with DMD in a “one-stop-shop” setting. The aim is to cater for all of the patient’s specialist care needs in one sitting, averting the need for multiple attendances. This also results in continuity of care, with staff being familiar with the particular needs of this group of patients attending over time. Management of challenging discussions around ICD device considerations are best made in this setting, with multiple inputs from the team, patient and carers. Although not cited as a reason for non-attendance for any diagnostic investigation by our cohort, the additional challenge with off-site CMR imaging is that patients are required to attend a further appointment, with repetition of the full set of obstacles that these patients are required to overcome when travelling for medical and care needs. The provision of dedicated on-site CMR slots would negate this further challenge, however this may be logistically and financially challenging in a publicly funded healthcare setting. The high level of agreement between TTE and CMR in our study, and the acquisition of diagnostic quality images in the large majority of patients, supports the argument to continue the use of TTE as the standard of care imaging modality in this clinical context. Furthermore, its widespread availability, low cost and portability makes TTE a more convenient test than CMR in patients with DMD. Noting that extensive fibrosis was seen in 88% of patients who underwent CMR in this study, in addition to the complete penetrance of DMD cardiomyopathy seen in other studies, there is an argument for empirical and aggressive medical treatment for all patients with DMD regardless of imaging findings. This is the approach undertaken in our Centre. This would largely negate the need for CMR, especially in patients on whom high quality TTE imaging could be obtained. Regardless of whether CMR data is deemed necessary, it seems rational based on current evidence that all patients should undergo TTE imaging, with CMR being utilised as an adjunctive modality. The range of difficulties reported with diagnostic imaging by both operators and patients and caregivers related largely to mobility, positioning and discomfort. These issues are universally apparent in this unique cohort of patients, and the natural history of DMD is such that improvements in patient factors are likely to be minimal. Therefore difficulties with imaging should be regarded primarily as difficulties specific to the imaging centre rather than the patient. Increased resourcing of imaging centres to cater to the particular mobility and care needs of these patients is likely to result not only in improved care delivery but also in better quality diagnostic imaging. Limitations: This single centre study provides useful information on the barriers to obtaining diagnostic imaging in DMD. The small sample size and the fact that the data presented are only representative of a single centre cohort may affect generalisability of results, however this tertiary referral centre caters to a large catchment area serving urban and rural populations with broad variation in socioeconomic conditions. Therefore data should reflect a reasonably diverse cohort. Incomplete quantitative measurements in TTE studies were noted, especially missing LV diameter, wall thickness, and occasionally diastology. Assessment of RV function was missing in cases where the RV was not well visualised. As a consequence there was heterogeneity in reports and comparison of data. This was often due to difficulties cited in the discussion above in relation to acquisition of TTE images, however there was also inter-operator variability in reporting of these parameters. A standardised format of quantitative measurement and reporting would likely strengthen the TTE data presented here. This study evaluated young adult patients with DMD after transition to the adult healthcare system. Due to current legislative and local regulations regarding sharing of patient data, access to historical imaging was limited to reports brought voluntarily by patients to the adult clinic. Thus the comparison of TTE findings over time is limited by a short mean follow-up time. Conclusion Our study highlights the common practical barriers to successful diagnostic imaging in adult patients with Duchenne Muscular Dystrophy cardiomyopathy. High rates of suboptimal TTE imaging were observed alongside high rates of failure to carry out CMR, although there was good agreement between modalities when both were undertaken. The obstacles included muscular contraction deformity, inability to lie flat, reliance on respiratory and other support devices, and difficulty with positioning for TTE scanning. Transportation and logistic considerations were also cited as an additional challenge by patients and caregivers. In some cases we observed opportunities to enable patients to participate more fully in diagnostic imaging. Trained staff to aid with positioning during scanning and assistance with transportation were two key areas where we identified modifiable interactions between impairment and environment which could aid in facilitation of diagnostic imaging for patients. The use of multimodality imaging, namely TTE and CMR, not only contributes important prognostic data on the progression of this universally penetrant cardiomyopathy, but also offers two distinct prospects to obtain sufficient diagnostic data to guide management. Therefore we highlight the importance of offering multimodality imaging to patients with DMD, and promoting practical strategies to support patients in modifying and overcoming environmental challenges to diagnostic quality imaging. Declarations Conflict of interest: The authors have no conflicts of interest to declare. There are no grants, contracts or other sources of funding associated with this research Data availability statement: The data underlying this article will be shared on reasonable request to the corresponding author, in aggregate form in order to protect the privacy of the individual study participants. References Blake DJ, Weir A, Newey SE, Davies KE. Function and genetics of dystrophin and dystrophin-related proteins in muscle. Physiol Rev. 2002;82(2):291-329. Nowak KJ, Davies KE. Duchenne muscular dystrophy and dystrophin: pathogenesis and opportunities for treatment. EMBO Rep. 2004;5(9):872-6. Duan D, Goemans N, Takeda S, Mercuri E, Aartsma-Rus A. Duchenne muscular dystrophy. Nat Rev Dis Primers. 2021;7(1):13. Mah JK, Korngut L, Dykeman J, Day L, Pringsheim T, Jette N. A systematic review and meta-analysis on the epidemiology of Duchenne and Becker muscular dystrophy. Neuromuscul Disord. 2014;24(6):482-91. Eagle M, Baudouin SV, Chandler C, Giddings DR, Bullock R, Bushby K. Survival in Duchenne muscular dystrophy: improvements in life expectancy since 1967 and the impact of home nocturnal ventilation. Neuromuscul Disord. 2002;12(10):926-9. Nigro G, Comi LI, Politano L, Bain RJ. The incidence and evolution of cardiomyopathy in Duchenne muscular dystrophy. Int J Cardiol. 1990;26(3):271-7. Markham LW, Kinnett K, Wong BL, Woodrow Benson D, Cripe LH. Corticosteroid treatment retards development of ventricular dysfunction in Duchenne muscular dystrophy. Neuromuscul Disord. 2008;18(5):365-70. Kamdar F, Garry DJ. Dystrophin-Deficient Cardiomyopathy. J Am Coll Cardiol. 2016;67(21):2533-46. Power LCOG, G. L; Hornung, T. S; Jefferies, C; Gusso, S; Hofman, P. L. Imaging the heart to detect cardiomyopathy in Duchenne muscular dystrophy: A review. Neuromuscular Disorders. 2018;28(9):717-30. Sanchez FW, C; Gutierrez, J. M; Mestroni, L; Hanneman, K; Vargas, D. Cardiac MR Imaging of Muscular Dystrophies. Current Problems in Diagnostic Radiology. 2022;51(2):225-34. McDonagh TA, Metra M, Adamo M, Gardner RS, Baumbach A, Bohm M, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2021;42(36):3599-726. Group CTS. Effects of enalapril on mortality in severe congestive heart failure. Results of the Cooperative North Scandinavian Enalapril Survival Study (CONSENSUS). N Engl J Med. 1987;316(23):1429-35. Pitt B, Zannad F, Remme WJ, Cody R, Castaigne A, Perez A, et al. The effect of spironolactone on morbidity and mortality in patients with severe heart failure. Randomized Aldactone Evaluation Study Investigators. N Engl J Med. 1999;341(10):709-17. Poole-Wilson PA, Swedberg K, Cleland JG, Di Lenarda A, Hanrath P, Komajda M, et al. Comparison of carvedilol and metoprolol on clinical outcomes in patients with chronic heart failure in the Carvedilol Or Metoprolol European Trial (COMET): randomised controlled trial. Lancet. 2003;362(9377):7-13. Bourke JP, Watson G, Muntoni F, Spinty S, Roper H, Guglieri M, et al. Randomised placebo-controlled trial of combination ACE inhibitor and beta-blocker therapy to prevent cardiomyopathy in children with Duchenne muscular dystrophy? (DMD Heart Protection Study): a protocol study. BMJ Open. 2018;8(12):e022572. Giatrakos N, Kinali M, Stephens D, Dawson D, Muntoni F, Nihoyannopoulos P. Cardiac tissue velocities and strain rate in the early detection of myocardial dysfunction of asymptomatic boys with Duchenne's muscular dystrophy: relationship to clinical outcome. Heart. 2006;92(6):840-2. Melero-Ferrer JL, Lopez-Vilella R, Morillas-Climent H, Sanz-Sanchez J, Sanchez-Lazaro IJ, Almenar-Bonet L, et al. Novel Imaging Techniques for Heart Failure. Card Fail Rev. 2016;2(1):27-34. Braga JR, Leong-Poi H, Rac VE, Austin PC, Ross HJ, Lee DS. Trends in the Use of Cardiac Imaging for Patients With Heart Failure in Canada. JAMA Netw Open. 2019;2(8):e198766. Frankel KA, Rosser RJ. The pathology of the heart in progressive muscular dystrophy: epimyocardial fibrosis. Hum Pathol. 1976;7(4):375-86. Pellikka PA, She L, Holly TA, Lin G, Varadarajan P, Pai RG, et al. Variability in Ejection Fraction Measured By Echocardiography, Gated Single-Photon Emission Computed Tomography, and Cardiac Magnetic Resonance in Patients With Coronary Artery Disease and Left Ventricular Dysfunction. JAMA Netw Open. 2018;1(4):e181456. Tables Table 1: Baseline characteristics and medications use: Age (median years, StD) 20, 4.3 Mean HR 88BPM Beta blocker 79% ACEi 75% MRA 50% Corticosteroid 50% Table 2: TTE parameters (Follow-up, Initial study) Age (Median +/- StD years) 22 +/-4.7 18 +/-1 LVEF (Mean +/- StD %) 46 +/-12 51 +/-11 LVIVSd (mm) 8 +/-2 LVPWd (mm) 7 +/-2 LVIDd (mm) 44 +/-1 LVIDs (mm) 36 +/-1 E/A 1.5 +/-0.3 RV dysfunction (N, %) 3, 9% 1, 3% MR mild (N, %) 3, 9% MR trace (N, %) 10, 30% AR > trivial 0 TR > trivial 0 Table 3: MRI parameters LVEF (median) 43% Normal LVEF (N, %) 3, 38% Extensive midwall fibrosis (N, %) 7, 100%* *Contrast not administered in N=1 Regional wall motion abnormality (N, %) 4, 50% Additional Declarations No competing interests reported. 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Murray","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA80lEQVRIiWNgGAWjYNCDjw0gkrHxAH5lzAgm48wGBgkg1UC8FmZesBYGBrxazNn7Dz6uqNmWuH324WfStjts6nTbDwNtqbGJxqXFsucws+GZY7cT55xLM5POPZMmYXYmEajlWFpuAw4tBjeS2SQbG24nzuBhAGppOyxhdgCohbHhMG4t9x+z/4RoYf8mbQnScv4hAS03mNkYIVp4zKQZQVpuELDFsifZWLLh2G1joJZiy962NMltN4C2JODxizn7wYcfG2puywIdtvHGzzYbfrPz6Q8ffKixwe0wJDaLBJyZgEM5uhbmD3gUjoJRMApGwQgGANSnYbBZaWlBAAAAAElFTkSuQmCC","orcid":"","institution":"Beaumont Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Peter","middleName":"C.","lastName":"Murray","suffix":""},{"id":275125297,"identity":"b6653197-5c32-4e42-9d55-62462049bc69","order_by":1,"name":"Ailis Pollock","email":"","orcid":"","institution":"Beaumont Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Ailis","middleName":"","lastName":"Pollock","suffix":""},{"id":275125298,"identity":"3733d53b-fd57-4e80-905e-07dd76f88151","order_by":2,"name":"Katie Hewitt","email":"","orcid":"","institution":"Beaumont Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Katie","middleName":"","lastName":"Hewitt","suffix":""},{"id":275125299,"identity":"037570f2-dbf9-4a21-b3a4-07cf0c6efd5b","order_by":3,"name":"Jennifer O'sullivan","email":"","orcid":"","institution":"Beaumont Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jennifer","middleName":"","lastName":"O'sullivan","suffix":""},{"id":275125300,"identity":"949ca5ea-7ab0-46b8-9e89-e431baafc318","order_by":4,"name":"Richard Sheahan","email":"","orcid":"","institution":"Beaumont Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Richard","middleName":"","lastName":"Sheahan","suffix":""}],"badges":[],"createdAt":"2024-02-26 16:22:59","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3991442/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3991442/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":51969836,"identity":"ee54d09f-de25-43a1-9105-6d00039bcd14","added_by":"auto","created_at":"2024-03-04 18:45:34","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":150897,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-3991442/v1/c65584da89009c852048e2dd.png"},{"id":51969835,"identity":"4adb7ee8-ae4d-4e17-8f30-933b6d93a3a9","added_by":"auto","created_at":"2024-03-04 18:45:34","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":142719,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-3991442/v1/04509405721570e63c41858c.png"},{"id":51969837,"identity":"1f7da130-e5b4-4a15-940d-2f65ae11b325","added_by":"auto","created_at":"2024-03-04 18:45:34","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":97132,"visible":true,"origin":"","legend":"\u003cp\u003eUnnumbered image in the Results section.\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-3991442/v1/99b6e78a45e8580df29577ff.png"},{"id":52927902,"identity":"59b47fd7-8130-473f-8509-b50da9b19314","added_by":"auto","created_at":"2024-03-18 19:05:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":613525,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3991442/v1/6b4ef187-5baf-4fff-bfb1-96a078efe06d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Real World Barriers to Diagnostic Cardiac Imaging in Adults with Duchenne Muscular Dystrophy Cardiomyopathy","fulltext":[{"header":"Background","content":"\u003cp\u003eDuchenne muscular dystrophy (DMD) is an X-linked recessive disease caused by mutations in the gene encoding dystrophin\u003csup\u003e1\u003c/sup\u003e, a protein essential to the integrity of the cytoskeleton of striated muscle. The complete absence of dystrophin seen in DMD\u003csup\u003e2\u003c/sup\u003e, and resultant progressive atrophy, manifests clinically as gait disturbance with subsequent loss of ambulation, and ultimately cardiac and respiratory failure\u003csup\u003e3\u003c/sup\u003e. Its prevalence is approximately 4.78 per 100,000 males\u003csup\u003e4\u003c/sup\u003e. The natural history of DMD carries a poor prognosis, with death at a mean age of 14.4 years reported in some studies\u003csup\u003e5\u003c/sup\u003e. The introduction of non-invasive ventilation has increased this by approximately 10 years, however. Consequently, cardiomyopathy, which is universally apparent over 18 years of age, has become the leading cause of mortality\u003csup\u003e6\u003c/sup\u003e. Monitoring for pre-clinical evidence of cardiomyopathy presents a challenge in this unique cohort of patients. Contractures, chest wall deformities, ventilation abnormalities and scoliosis are some of the barriers to diagnostic quality imaging of patients with DMD which have been alluded to in previous studies\u003csup\u003e7, 8\u003c/sup\u003e.While more recent research has highlighted the utility of CMR in the evaluation of patients with muscular dystrophy for the presence of preclinical cardiomyopathy\u003csup\u003e9, 10\u003c/sup\u003e, there is a lack of data regarding the extent to which these issues impact on the quality and practicability of cardiac imaging in this group of patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAim\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe aim of this study was to evaluate the optimal strategy for cardiac imaging in young adults with DMD with regard to the practicalities of imaging in individual patients, and to review the extent to which these issues impact on the quality and practicability of cardiac imaging in this group of patients.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eWe conducted a prospective cohort study comparing the diagnostic utility of CMR with TTE in patients with DMD. All patients attending a Comprehensive Multidisciplinary Adult DMD clinic over a 4 year period were enrolled. The clinic provided a single One Stop Visit with an extensive review with Advanced Specialist Care from Pulmonologist, Cardiologist, Neurologist, Physiotherapist, Occupational Therapist, Nutritionist, and Social Worker. All patients were offered referral for CMR and had a TTE study conducted.\u003c/p\u003e\n\u003cp\u003eData collection occurred at baseline and at patients\u0026rsquo; clinical review. Parameters included were age, TTE derived EF at baseline and follow-up, time to follow-up, ambulatory status, use of respiratory adjuncts, whether CMR was performed and, if so, presence or absence of fibrosis and CMR derived EF. In the case of non-attendance for their investigation, we recorded the reason cited by the patient or caregiver. All data collection, storage and reporting was carried out in accordance with local governance procedures, and national and international data protection regulations.\u003c/p\u003e\n\u003cp\u003eData were analysed for agreement in LVEF between modalities with results illustrated using a Bland-Altman plot. Differences in non-attendance and non-diagnostic exam rates, and the reason for observed differences between modalities, were reported in a qualitative manner.\u003c/p\u003e\n\u003cp\u003eEthical approval\u003c/p\u003e\n\u003cp\u003eThe study protocol was reviewed and ethically approved by the Beaumont Hospital Clinical Audit \u0026amp; Governance Committee (Institutional Review Board reference number CA2023/133).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eWe enrolled a total of 33 patients consecutively, all of whom were male. Baseline characteristics and medication use are shown in Table 1. The median age was 20, standard deviation 4.3 years. The box plot depicts the number of patients broken down by LVEF range on TTE at enrolment and follow-up.\u003c/p\u003e\n\u003cp\u003eTable 2 depicts TTE parameters measured for each patient at follow-up, and initial study. We note that of the 13 patients with any degree of mitral regurgitation (MR), 12 (92%) had LVEF less than 55%. Thus the presence of any degree of MR strongly correlates to LVSD in our study cohort. Absence of MR did not correlate well with presence or absence of LVSD, however.\u003c/p\u003e\n\u003cp\u003eTTE was conducted in all patients. Mean EF was 51% at initial echo and 45% at follow-up. Mean follow-up period was 3 years, 3 months. Although imaging was reported as \u0026ldquo;suboptimal\u0026rdquo; or \u0026ldquo;limited\u0026rdquo; in 75% of cases, only 9% of studies (N=3) were considered non-diagnostic.Patient positioning / immobility was cited as the reason for suboptimal imaging in most cases.\u003c/p\u003e\n\u003cp\u003eEight patients (25%) underwent a diagnostic quality CMR. The remainder were offered or attempted the scan but declined to attend or attended and were unable to have a diagnostic quality scan for the reasons given. Results are depicted in table 3. Extensive midwall fibrosis was reported in 100% of studies where IV contrast was administered (N=7). Contrast evaluation was not performed in N=1 due to difficulty obtaining IV access, however T1 mapping was suggestive of midwall fibrosis in this case also. Of those with confirmed fibrosis, 14% (N=1) exhibited normal LVEF. The extent of fibrosis was reported in a semi-quantitative manner, with \u0026ldquo;significant\u0026rdquo; or \u0026ldquo;extensive\u0026rdquo; fibrosis reported in all 8 cases. Image 1 depicts a flowchart showing the number of patients who underwent CMR, as well as reasons not undertaken. The primary reason for non-completion of CMR was recorded as \u0026ldquo;patient unable to lie flat\u0026rdquo; or \u0026ldquo;could not tolerate\u0026rdquo; due to contractures in all cases except for 1, where \u0026ldquo;poor IV access\u0026rdquo; was cited. One patient requiring continuous non-invasive ventilation when lying recumbent was unable to attempt scanning for this reason also. Difficulties encountered with travel were an obstacle to further imaging described frequently by patients and caregivers in our study cohort, however these difficulties were not cited as the reason for failure to complete a scan in any case.\u003c/p\u003e\n\u003cp\u003eDespite the difficulties encountered with both imaging modalities, it is notable that our study found a high degree of correlation between TTE and CMR derived measurement of LV ejection fraction. We used the Bland-Altman plot to assess for clinically acceptable agreement between modalities rather than calculating a correlation coefficient, given the inherent limitations of correlation as a surrogate for agreement in statistical analysis, as well as the lack of any standardised acceptable limits for agreement in LVEF between modalities. We found that there was a high level of agreement between TTE and CMR, with a mean difference in reported LVEF between modalities of 1.625% (95% CI -9.0 - 5.8). Image 2 depicts the results recorded on the Bland-Altman plot.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study shows Real-world data from a consecutive Adult population with Duchenne Muscular Dystrophy that show only a small proportion of patients enrolled had both diagnostic quality TTE (91%) and CMR (25%) performed successfully. Our study is the first to report on the actual barriers to obtaining an evaluable CMR. The array of barriers to successful imaging which were encountered prove problematic in obtaining accurate diagnostic information on LV function as well as potentially useful prognostic information such as strain rate and fibrosis, which may be important in guiding treatment decisions.\u003c/p\u003e\n\u003cp\u003eCurrent evidence for therapeutic strategies based on imaging parameters\u003c/p\u003e\n\u003cp\u003eAs in other forms of heart failure (HF), incident left ventricular (LV) systolic dysfunction in DMD should prompt the introduction of treatment with beta adrenergic blockade, renin-angiotensin activation system inhibition, mineralocorticoid receptor antagonist and sodium-glucose cotransporter 2 inhibitor drugs\u003csup\u003e11\u003c/sup\u003e, and Ivabradine. Established TTE parameters, such as reduction in LV ejection fraction and fractional shortening, are well studied in the seminal clinical trials of these drug classes\u003csup\u003e12-14\u003c/sup\u003e. International bodies therefore recommend treatments based on cut-off values in these parameters.\u003c/p\u003e\n\u003cp\u003eDue to complete penetrance of cardiomyopathy in DMD, however, early intervention with conventional drugs is the currently accepted consensus strategy to prevent or delay the onset of clinical HF. The optimal timing of treatment has yet to be determined, and clinical trials are ongoing to ascertain when these drugs should be initiated before the onset of LV systolic dysfunction\u003csup\u003e15\u003c/sup\u003e. The emergence of tissue Doppler and strain imaging, which correlate well with subsequent development of DMD HF\u003csup\u003e16\u003c/sup\u003e, has already seen a role for these parameters in early detection and instigation of treatment. Similarly, CMR parameters such as late gadolinium enhancement of the LV midwall can provide invaluable early prognostic information about the extent of fibrosis, and predict subsequent deterioration in systolic function.\u003c/p\u003e\n\u003cp\u003eComparison of modalities: TTE\u003c/p\u003e\n\u003cp\u003eDespite recent advances in cardiac magnetic resonance imaging (CMR) and computed tomography (CCT), transthoracic echocardiography (TTE) remains the most commonly used imaging modality in the investigation of cardiomyopathy and heart failure, and in their follow-up\u003csup\u003e17\u003c/sup\u003e. Although the comparatively low cost is likely to be the principal motivation behind its ongoing use in preference to other modalities\u003csup\u003e18\u003c/sup\u003e, TTE continues to bear certain important advantages over CMR and CCT. The widespread availability of TTE makes it accessible to patients who are too unwell or clinically unstable to undergo other departmental imaging studies. Its portability has unique implications in DMD, where practical issues such as immobility and lack of appropriate transportation can render travel to centres with CCT and CMR capability unfeasible for patients. Moreover, the prevalence of contractures seen in DMD limits entry into the CMR scanner, and this is less problematic with a mobile modality such as TTE.\u003c/p\u003e\n\u003cp\u003eFactors limiting the diagnostic accuracy and utility of TTE are also encountered frequently. Image quality is often suboptimal in this almost-universally non-ambulatory cohort as correct positioning is infrequently achieved. Neuromuscular scoliosis and chest wall deformity present a further barrier to the acquisition of good acoustic windows in many cases. In addition to the factors limiting image acquisition, TTE interpretation is also highly operator dependent. This presents unique challenges in serial follow-up examinations when monitoring patients for deteriorating LV function. Varying degrees of correlation have been reported in studies comparing CMR with TTE.\u003c/p\u003e\n\u003cp\u003eComparison of modalities: CMR\u003c/p\u003e\n\u003cp\u003ePostmortem histopathological examinations in DMD show a paucity of cardiac myocytes with a distinctive pattern of fibrofatty infiltration with early preponderance for the posterior left ventricular wall\u003csup\u003e19\u003c/sup\u003e. CMR can detect this myocardial fibrosis using gadolinium contrast enhancement. The extent of late gadolinium enhancing myocardium indicates the degree of fibrosis, and strongly correlates with the risk of subsequent deterioration in LVEF. Consequently, it is useful in screening for early myocardial involvement prior to the onset of LV systolic dysfunction. Unfortunately only 25% of our patients were able to have CMR performed due to the inherent patient-based and system-based obstacles described above.\u003c/p\u003e\n\u003cp\u003eCMR strain imaging is also increasingly used, and declining circumferential strain even precedes myocardial fibrosis. These technologies are therefore emerging as pre-clinical predictors of earlier and more severe cardiomyopathy, with greater accuracy than conventional TTE imaging. Thus CMR is likely to become much more widespread as a tool to inform risk stratification in DMD. Research is ongoing to investigate how this may guide the timing and optimisation of pre-clinical intervention in cardiomyopathy.\u003c/p\u003e\n\u003cp\u003eDespite these promising advances, CMR has inherent limitations specific to the DMD population of patients. Its cost and consequent lack of widespread availability means that travel to centres with CMR capability may present an obstacle to patients attending for this investigation, especially with regard to immobility and transport. Neuromuscular contractures resulting in scoliosis and fixed flexion deformity of the hip joints are well described and present a barrier to patients entering the MRI scanner (and precluded scanning in 27% of our study cohort). Additionally, 3% of patients required continuous non-invasive ventilation. These devices are generally incompatible with MRI, and therefore scanning could not be achieved in patients who were fully dependent.\u003c/p\u003e\n\u003cp\u003eThe use of a multi-modality approach increases diagnostic yield, with the finding of early and extensive pattern of fibrosis on CMR prompting intensification of treatment prior to deterioration in systolic function. Despite the clinical value of this diagnostic information, obtaining it can be onerous on patients, causing significant disruption to routine as well as discomfort at times.\u003c/p\u003e\n\u003cp\u003eIt is noted that patients with DMD and their caregivers cite numerous difficulties in attending appointments, due to considerations around wheelchair-accessible travel arrangements, distance to travel and time constraints. Therefore, as the use of imaging increases, it may necessitate tailoring the use of different modalities to clinical need, with due regard to the patient\u0026rsquo;s ambulatory state, severity of contractures and dependence on respiratory support, as well as other practical considerations not limited to transportation and the availability of caregiver support.\u003c/p\u003e\n\u003cp\u003eImage Concordance\u003c/p\u003e\n\u003cp\u003eAlthough image quality was suboptimal in a large proportion of TTE studies, it is noteworthy that there was a high level of agreement in LVEF reported on TTE compared with CMR, which is at odds with some previous studies\u003csup\u003e20\u003c/sup\u003e where more heterogeneity was observed. We found that LVEF agreed to within +/- 5% in 88% of patients who underwent both TTE and CMR. This was deemed to be a very satisfactory level of agreement to guide clinical decision making, and further supports the use of TTE as the first line of diagnostic imaging in patients with significant mobility impairment.\u003c/p\u003e\n\u003cp\u003eTechnical considerations\u003c/p\u003e\n\u003cp\u003eAlthough the technical expertise of radiographers and sonographers is beyond the scope of this article, it is acknowledged that a significant skill set is employed in performing high quality studies on patients with significant mobility impairment. At the time of writing, a literature search for training of cardiac sonographers in imaging patients with disabilities did not yield any relevant published results. Specialist training for operators in the practical considerations of this unique patent cohort may well improve imaging yield. Given the frequent citing by our technicians of difficulty with patient positioning as a major factor in suboptimal TTE image quality, it is postulated that additional resourcing of TTE units with healthcare staff to aid with positioning may help to further optimise acoustic windows.\u003c/p\u003e\n\u003cp\u003eA Single Multidisciplinary Team Clinical Review\u003c/p\u003e\n\u003cp\u003ePatients with DMD are almost entirely non-ambulatory and dependent on wheelchairs for mobility, as well as carers for assistance with transport and personal care. Specialised equipment is required to aid with transportation, as well as various devices for respiratory support which require trained operators to be present. This results in a significant stress for patients as well as high demand on their caregivers when numerous different appointments are necessary. The recent establishment of tertiary referral centres such as ours is done with the intention of honing advanced clinical skill from multi-disciplinary services resulting in a broad range of specialised services being made available to patients with DMD in a \u0026ldquo;one-stop-shop\u0026rdquo; setting. The aim is to cater for all of the patient\u0026rsquo;s specialist care needs in one sitting, averting the need for multiple attendances. This also results in continuity of care, with staff being familiar with the particular needs of this group of patients attending over time. Management of challenging discussions around ICD device considerations are best made in this setting, with multiple inputs from the team, patient and carers.\u003c/p\u003e\n\u003cp\u003eAlthough not cited as a reason for non-attendance for any diagnostic investigation by our cohort, the additional challenge with off-site CMR imaging is that patients are required to attend a further appointment, with repetition of the full set of obstacles that these patients are required to overcome when travelling for medical and care needs. The provision of dedicated on-site CMR slots would negate this further challenge, however this may be logistically and financially challenging in a publicly funded healthcare setting.\u003c/p\u003e\n\u003cp\u003eThe high level of agreement between TTE and CMR in our study, and the acquisition of diagnostic quality images in the large majority of patients, supports the argument to continue the use of TTE as the standard of care imaging modality in this clinical context. Furthermore, its widespread availability, low cost and portability makes TTE a more convenient test than CMR in patients with DMD. Noting that extensive fibrosis was seen in 88% of patients who underwent CMR in this study, in addition to the complete penetrance of DMD cardiomyopathy seen in other studies, there is an argument for empirical and aggressive medical treatment for all patients with DMD regardless of imaging findings. This is the approach undertaken in our Centre. This would largely negate the need for CMR, especially in patients on whom high quality TTE imaging could be obtained. Regardless of whether CMR data is deemed necessary, it seems rational based on current evidence that all patients should undergo TTE imaging, with CMR being utilised as an adjunctive modality.\u003c/p\u003e\n\u003cp\u003eThe range of difficulties reported with diagnostic imaging by both operators and patients and caregivers related largely to mobility, positioning and discomfort. These issues are universally apparent in this unique cohort of patients, and the natural history of DMD is such that improvements in patient factors are likely to be minimal. Therefore difficulties with imaging should be regarded primarily as difficulties specific to the imaging centre rather than the patient. Increased resourcing of imaging centres to cater to the particular mobility and care needs of these patients is likely to result not only in improved care delivery but also in better quality diagnostic imaging.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis single centre study provides useful information on the barriers to obtaining diagnostic imaging in DMD. The small sample size and the fact that the data presented are only representative of a single centre cohort may affect generalisability of results, however this tertiary referral centre caters to a large catchment area serving urban and rural populations with broad variation in socioeconomic conditions. Therefore data should reflect a reasonably diverse cohort.\u003c/p\u003e\n\u003cp\u003eIncomplete quantitative measurements in TTE studies were noted, especially missing LV diameter, wall thickness, and occasionally diastology. Assessment of RV function was missing in cases where the RV was not well visualised. As a consequence there was heterogeneity in reports and comparison of data. This was often due to difficulties cited in the discussion above in relation to acquisition of TTE images, however there was also inter-operator variability in reporting of these parameters. A standardised format of quantitative measurement and reporting would likely strengthen the TTE data presented here.\u003c/p\u003e\n\u003cp\u003eThis study evaluated young adult patients with DMD after transition to the adult healthcare system. Due to current legislative and local regulations regarding sharing of patient data, access to historical imaging was limited to reports brought voluntarily by patients to the adult clinic. Thus the comparison of TTE findings over time is limited by a short mean follow-up time.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur study highlights the common practical barriers to successful diagnostic imaging in adult patients with Duchenne Muscular Dystrophy cardiomyopathy. High rates of suboptimal TTE imaging were observed alongside high rates of failure to carry out CMR, although there was good agreement between modalities when both were undertaken. The obstacles included muscular contraction deformity, inability to lie flat, reliance on respiratory and other support devices, and difficulty with positioning for TTE scanning. Transportation and logistic considerations were also cited as an additional challenge by patients and caregivers.\u003c/p\u003e\n\u003cp\u003eIn some cases we observed opportunities to enable patients to participate more fully in diagnostic imaging. Trained staff to aid with positioning during scanning and assistance with transportation were two key areas where we identified modifiable interactions between impairment and environment which could aid in facilitation of diagnostic imaging for patients. The use of multimodality imaging, namely TTE and CMR, not only contributes important prognostic data on the progression of this universally penetrant cardiomyopathy, but also offers two distinct prospects to obtain sufficient diagnostic data to guide management. Therefore we highlight the importance of offering multimodality imaging to patients with DMD, and promoting practical strategies to support patients in modifying and overcoming environmental challenges to diagnostic quality imaging.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors have no conflicts of interest to declare.\u003c/p\u003e\n\u003cp\u003eThere are no grants, contracts or other sources of funding associated with this research\u003c/p\u003e\u003cp\u003e\u0026nbsp;\u003cstrong\u003eData availability statement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data underlying this article will be shared on reasonable request to the corresponding author, in aggregate form in order to protect the privacy of the individual study participants.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBlake DJ, Weir A, Newey SE, Davies KE. Function and genetics of dystrophin and dystrophin-related proteins in muscle. Physiol Rev. 2002;82(2):291-329.\u003c/li\u003e\n\u003cli\u003eNowak KJ, Davies KE. Duchenne muscular dystrophy and dystrophin: pathogenesis and opportunities for treatment. EMBO Rep. 2004;5(9):872-6.\u003c/li\u003e\n\u003cli\u003eDuan D, Goemans N, Takeda S, Mercuri E, Aartsma-Rus A. Duchenne muscular dystrophy. Nat Rev Dis Primers. 2021;7(1):13.\u003c/li\u003e\n\u003cli\u003eMah JK, Korngut L, Dykeman J, Day L, Pringsheim T, Jette N. A systematic review and meta-analysis on the epidemiology of Duchenne and Becker muscular dystrophy. Neuromuscul Disord. 2014;24(6):482-91.\u003c/li\u003e\n\u003cli\u003eEagle M, Baudouin SV, Chandler C, Giddings DR, Bullock R, Bushby K. Survival in Duchenne muscular dystrophy: improvements in life expectancy since 1967 and the impact of home nocturnal ventilation. Neuromuscul Disord. 2002;12(10):926-9.\u003c/li\u003e\n\u003cli\u003eNigro G, Comi LI, Politano L, Bain RJ. The incidence and evolution of cardiomyopathy in Duchenne muscular dystrophy. Int J Cardiol. 1990;26(3):271-7.\u003c/li\u003e\n\u003cli\u003eMarkham LW, Kinnett K, Wong BL, Woodrow Benson D, Cripe LH. Corticosteroid treatment retards development of ventricular dysfunction in Duchenne muscular dystrophy. Neuromuscul Disord. 2008;18(5):365-70.\u003c/li\u003e\n\u003cli\u003eKamdar F, Garry DJ. Dystrophin-Deficient Cardiomyopathy. J Am Coll Cardiol. 2016;67(21):2533-46.\u003c/li\u003e\n\u003cli\u003ePower LCOG, G. L; Hornung, T. S; Jefferies, C; Gusso, S; Hofman, P. L. Imaging the heart to detect cardiomyopathy in Duchenne muscular dystrophy: A review. Neuromuscular Disorders. 2018;28(9):717-30.\u003c/li\u003e\n\u003cli\u003eSanchez FW, C; Gutierrez, J. M; Mestroni, L; Hanneman, K; Vargas, D. Cardiac MR Imaging of Muscular Dystrophies. Current Problems in Diagnostic Radiology. 2022;51(2):225-34.\u003c/li\u003e\n\u003cli\u003eMcDonagh TA, Metra M, Adamo M, Gardner RS, Baumbach A, Bohm M, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2021;42(36):3599-726.\u003c/li\u003e\n\u003cli\u003eGroup CTS. Effects of enalapril on mortality in severe congestive heart failure. Results of the Cooperative North Scandinavian Enalapril Survival Study (CONSENSUS). N Engl J Med. 1987;316(23):1429-35.\u003c/li\u003e\n\u003cli\u003ePitt B, Zannad F, Remme WJ, Cody R, Castaigne A, Perez A, et al. The effect of spironolactone on morbidity and mortality in patients with severe heart failure. Randomized Aldactone Evaluation Study Investigators. N Engl J Med. 1999;341(10):709-17.\u003c/li\u003e\n\u003cli\u003ePoole-Wilson PA, Swedberg K, Cleland JG, Di Lenarda A, Hanrath P, Komajda M, et al. Comparison of carvedilol and metoprolol on clinical outcomes in patients with chronic heart failure in the Carvedilol Or Metoprolol European Trial (COMET): randomised controlled trial. Lancet. 2003;362(9377):7-13.\u003c/li\u003e\n\u003cli\u003eBourke JP, Watson G, Muntoni F, Spinty S, Roper H, Guglieri M, et al. Randomised placebo-controlled trial of combination ACE inhibitor and beta-blocker therapy to prevent cardiomyopathy in children with Duchenne muscular dystrophy? (DMD Heart Protection Study): a protocol study. BMJ Open. 2018;8(12):e022572.\u003c/li\u003e\n\u003cli\u003eGiatrakos N, Kinali M, Stephens D, Dawson D, Muntoni F, Nihoyannopoulos P. Cardiac tissue velocities and strain rate in the early detection of myocardial dysfunction of asymptomatic boys with Duchenne\u0026apos;s muscular dystrophy: relationship to clinical outcome. Heart. 2006;92(6):840-2.\u003c/li\u003e\n\u003cli\u003eMelero-Ferrer JL, Lopez-Vilella R, Morillas-Climent H, Sanz-Sanchez J, Sanchez-Lazaro IJ, Almenar-Bonet L, et al. Novel Imaging Techniques for Heart Failure. Card Fail Rev. 2016;2(1):27-34.\u003c/li\u003e\n\u003cli\u003eBraga JR, Leong-Poi H, Rac VE, Austin PC, Ross HJ, Lee DS. Trends in the Use of Cardiac Imaging for Patients With Heart Failure in Canada. JAMA Netw Open. 2019;2(8):e198766.\u003c/li\u003e\n\u003cli\u003eFrankel KA, Rosser RJ. The pathology of the heart in progressive muscular dystrophy: epimyocardial fibrosis. Hum Pathol. 1976;7(4):375-86.\u003c/li\u003e\n\u003cli\u003ePellikka PA, She L, Holly TA, Lin G, Varadarajan P, Pai RG, et al. Variability in Ejection Fraction Measured By Echocardiography, Gated Single-Photon Emission Computed Tomography, and Cardiac Magnetic Resonance in Patients With Coronary Artery Disease and Left Ventricular Dysfunction. JAMA Netw Open. 2018;1(4):e181456.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"641\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"2\"\u003e\n \u003cp\u003eTable 1: Baseline characteristics and medications use:\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eAge (median years, StD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e20, 4.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eMean HR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e88BPM\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eBeta blocker\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e79%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eACEi\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e75%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eMRA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.69110764430577%\" valign=\"top\"\u003e\n \u003cp\u003eCorticosteroid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.308892355694226%\" valign=\"top\"\u003e\n \u003cp\u003e50%\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=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"642\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"5\"\u003e\n \u003cp\u003eTable 2: TTE parameters (Follow-up, Initial study)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eAge (Median +/- StD years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e22 +/-4.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e18 +/-1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eLVEF (Mean +/- StD %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e46 +/-12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e51 +/-11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eLVIVSd (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e8 +/-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eLVPWd (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e7 +/-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eLVIDd (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e44 +/-1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eLVIDs (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e36 +/-1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eE/A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e1.5 +/-0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eRV dysfunction (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e3, 9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e1, 3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eMR mild (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e3, 9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eMR trace (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e10, 30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eAR \u0026gt; trivial\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.35413416536662%\" valign=\"top\"\u003e\n \u003cp\u003eTR \u0026gt; trivial\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.620904836193446%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"24.024960998439937%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\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=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"642\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd width=\"99.84423676012462%\" colspan=\"4\" style=\"width: 35.7915%;\"\u003e\n \u003cp\u003eTable 3: MRI parameters\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.57009345794393%\" colspan=\"3\" valign=\"top\" style=\"width: 27.7877%;\"\u003e\n \u003cp\u003eLVEF (median)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.274143302180686%\" valign=\"top\" style=\"width: 8.0038%;\"\u003e\n \u003cp\u003e43%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.57009345794393%\" colspan=\"3\" valign=\"top\" style=\"width: 27.7877%;\"\u003e\n \u003cp\u003eNormal LVEF (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.274143302180686%\" valign=\"top\" style=\"width: 8.0038%;\"\u003e\n \u003cp\u003e3, 38%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.57009345794393%\" colspan=\"3\" valign=\"top\" style=\"width: 27.7877%;\"\u003e\n \u003cp\u003eExtensive midwall fibrosis (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.274143302180686%\" valign=\"top\" style=\"width: 8.0038%;\"\u003e\n \u003cp\u003e7, 100%*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.57009345794393%\" colspan=\"3\" valign=\"top\" style=\"width: 27.7877%;\"\u003e\n \u003cp\u003e\u003cem\u003e*Contrast not administered in N=1\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.274143302180686%\" valign=\"top\" style=\"width: 8.0038%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"77.57009345794393%\" colspan=\"3\" valign=\"top\" style=\"width: 27.7877%;\"\u003e\n \u003cp\u003eRegional wall motion abnormality (N, %)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.274143302180686%\" valign=\"top\" style=\"width: 8.0038%;\"\u003e\n \u003cp\u003e4, 50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-3991442/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3991442/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eAims:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCardiomyopathy is universally penetrant in young adults with Duchenne muscular dystrophy (DMD), and is increasingly the preponderant cause of death. We sought to determine the rates of, and reasons for, failed diagnostic cardiac imaging in our DMD multidisciplinary care centre as well as the level of agreement between imaging modalities, in order to guide the optimal strategy for cardiac imaging in these patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods and results:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe followed all patients attending a Comprehensive Multidisciplinary Adult DMD clinic over 4 years. All attendees underwent transthoracic echocardiography (TTE) and were offered referral for cardiac MRI (CMR). Age, cardiac medications, left ventricular ejection fraction (LVEF), ambulatory status, airway adjuncts and presence and degree of cardiac fibrosis were recorded. A total of 33 patients enrolled, median age 20, with mean follow-up of 3 years and 3 months. Mean LVEF was 51% at enrollment and 45% at follow-up. Presence of any degree of mitral regurgitation correlated strongly to left ventricular systolic dysfunction. CMR was completed in just 25% of patients, all of whom had extensive midwall fibrosis. Of those in whom CMR failed, 52% were unable to lie flat or position correctly for scanning, predominantly due to muscle contractures. Despite suboptimal TTE imaging in 75%, there was good agreement in LVEF between CMR and TTE.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe found a high rate of failure to complete diagnostic cardiac imaging in this group of patients with impaired mobility. Our study highlights the importance of multimodality imaging, and practical strategies to overcome environmental obstacles to diagnostic imaging, to better guide aggressiveness of treatment for DMD and its inherent cardiomyopathy.\u003c/p\u003e","manuscriptTitle":"Real World Barriers to Diagnostic Cardiac Imaging in Adults with Duchenne Muscular Dystrophy Cardiomyopathy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-04 18:45:26","doi":"10.21203/rs.3.rs-3991442/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0b1792da-b2fb-4d0e-aecd-62a4a1cd75a9","owner":[],"postedDate":"March 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-03-18T19:05:13+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-04 18:45:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3991442","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3991442","identity":"rs-3991442","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}