Guidewire-Assisted 3D Mapping of Intramural Ventricular Arrhythmia Associated with Roemheld Syndrome: A Novel Case Report | 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 Case Report Guidewire-Assisted 3D Mapping of Intramural Ventricular Arrhythmia Associated with Roemheld Syndrome: A Novel Case Report Kunaraj Perumalu, Colin Yeo, Eric Tien Siang Lim This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8752849/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 Background Intramural PVCs (premature ventricular complexes) can be challenging to treat due to the deep origin within the myocardium. Case Summary A 45-year-old female with frequent palpitations triggered by abdominal pain was found to have a 24% PVC burden over 24 hours and preserved LVEF (left ventricular ejection fraction). An electrophysiology study and 3D electroanatomical mapping showed features of intramural PVCs. The coronary venous system was further mapped using VisionWire (0.014-inch). Catheter ablation at the basal right ventricular septum led to PVC suppression with non-inducibility of the clinical PVC at the end of the case. Conclusion The use of multimodality mapping and ablation tool has enabled us to manage cases effectively with good clinical outcomes. Roemheld syndrome is an understudied diagnosis and forgotten entity that can lead to PVCs via vagus nerve mediated mechanism. Intramural PVCs Vision Guide Wire Bipolar Ablation Ethanol Infusion Electrophysiology study Electroanatomical mapping Roemheld Syndrome Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Intramural PVCs originate in the interventricular septum or deep septal regions. Standard mapping and ablation catheters typically only reach the endocardial or epicardial surfaces, leaving intramural foci inaccessible for direct contact. Therefore, utilizing mapping guidewires helps delineate the origin of PVCs and simultaneously determines the appropriate approach to catheter ablation. Roemheld syndrome can be associated with PVCs due to a vagus nerve-mediated reflex triggered by gastrointestinal pressure. Case History A 45-year-old lady with no known co-morbids presented with frequent palpitations triggered by abdominal pain for 1 month. A 12-lead surface electrocardiogram and 24-hour Holter study showed non-outflow tract premature ventricular complexes with a burden of 24%. Her symptoms persisted despite being on oral bisoprolol. Her transthoracic echocardiogram and cardiac MRI showed preserved left ventricular ejection fraction with no evidence of structural heart disease or myocardial fibrosis. She underwent electrophysiology study and 3D electroanatomical mapping using Ensite X EP system. Two femoral vein punctures and one femoral artery puncture was done via modified Seldinger technique. Coronary sinus cannulation with SL-2 sheath support and an Advisor™ HD Grid was used to map RVOT (right ventricle outflow tract), right ventricle and the left ventricle. Local activation time (LAT) mapping showed consistent earliest premature ventricular complexes breakout site which was on time at the right ventricular septum. The LAT map demonstrated two discrete sites of premature ventricular complexes origin (from both superior and inferior right ventricular septum). Therefore, the left ventricle was mapped via retrograde aortic approach. The earliest breakout site from left ventricular septum was 5ms later than right ventricular septum. Based on the information obtained from both ventricular chambers, decision was made to map coronary sinus tributaries especially anterior interventricular vein using Biotronik VisionWire (0.014inch). A diagnostic multipurpose coronary catheter was used for support and ease accessibility of the vision wire further into septal branches. The earliest unipolar signal recorded at the septal perforator branch of coronary venous system was the earliest by 20ms. This coincides with the location of one of the septal perforator branches which was earlier captured via a coronary venous system venography. Therefore, combination of right ventricular, left ventricular and coronary venous system maps showed the premature ventricular complexes to be intramural in origin. Radiofrequency catheter ablation using half-normal saline (0.45% NaCl) was performed at the basal right ventricular septum. An energy of 35W to 40W was delivered for 60 seconds, with half normal saline irrigation and additional consolidation lesions. It led to acceleration of clinical premature ventricular complexes and their subsequent suppression with no further recurrences. Acute procedural success was achieved with non-inducibility of further clinical premature ventricular complexes. Discussion This case highlights the importance of multimodality tools in accurately locating the origin of intramural PVCs. Based on existing literature, intramural PVCs ablation can be challenging due to the risk of recurrences despite acutely successful ablation. The important considerations to look into, in cases of suspected intramural PVCs will be to compare the earliest activation time from different chambers of the heart whereby there will be significant borderline discrepancy in the activation time (neither late nor early). 1 The 12-lead surface electrocardiogram does provide adequate clue on the probability of a septal PVC origin which is absence of notching in inferior leads, narrow QRS pattern with earlier transition at V3 and more negative QRS at lead aVL than aVR. In our case, mapping the adjacent structures of the earliest exit site is important to appreciate the best approach. Mapping of both sides of the interventricular septum with isochronal LAT revealed that neither sides were truly early. This suggests that the endocardial surfaces are only the exit sites. Ablation of only the exit sites may not modify the substrate. This is a clue suggesting PVC origin from deep septal or intramural. This can be approached in different ways during 3D electroanatomical mapping and radiofrequency catheter ablation. 2,3 The coronary venous system should be further mapped in cases of suspected intramural PVCs, to identify the site of earliest activation. In our case, coronary sinus mapping focused on the anterior interventricular vein and its tributaries. 4,5 These were mapped using a 0.014-inch VisionWire in a unipolar configuration, which allowed for detailed anatomical reconstruction by reaching deep, small branches inaccessible to standard catheters. However, mapping via the venous system is only feasible if the area of interest is adjacent to the venous branches. 6 The 3D electroanatomical mapping of septal perforator branches of the coronary venous system is an important approach in cases of interventricular septum PVCs as it will guide endocardial ablation on the exact site to be targeted. 7,8 An alternative bail-out strategy for reaching areas inaccessible to standard ablation catheters is the use of a 0.014-inch PTFE (polytetrafluoroethylene)-coated guidewire, either for direct energy delivery or to facilitate ethanol ablation. 9,10 There are several non-epicardial methods to choose from when treating intramural PVCs. We opted to use a low-ionic irrigant solution, specifically half-normal saline (0.45% NaCl), which is supported by existing literature for its ability to deliver deeper and larger lesions. Low ionic content in the irrigant helps create high impedance cloud around the electrode, simultaneously increasing current density at the tip-tissue interface which enables larger and deeper lesion delivery. 11 Other options include bipolar ablation with 2 ablation catheters from opposite sides of the myocardial wall to ensure adequate transmural lesions, or unipolar ablation at multiple adjacent sites to mitigate the heat-sink effect and achieve a better clinical endpoint. 12 Irrigated needle ablation catheter is also possible to create intramural lesions, but it is not readily available in most centres. 13 To our knowledge, this is the first case report describing intramural PVCs associated with Roemheld syndrome. To the best of our knowledge, no large-scale studies have been published on this specific topic to date. A complex gut-brain-heart triad, linked primarily by the vagus nerve, may contribute to this phenomenon. This mechanism is attributed to autonomic imbalance caused by compensatory sympathetic activity and the subsequent release of catecholamines. 14 Pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 increase transmural dispersion of repolarization, creating an electrophysiological substrate that may potentially promote intramural PVCs. Intramural PVCs are considered challenging because of the potential for future recurrence. Therefore, comprehensive strategies in mapping and catheter ablation can be deployed to achieve a good clinical endpoint. Conclusions The use of coronary venous system guidewire mapping as an alternative to the epicardial approach is essential in areas inaccessible by standard mapping or ablation catheters. Mapping with coronary wires such as the Biotronik Vision wire allows us to map the small branches which are otherwise not accessible with even the smallest calibre diagnostic EP catheter. A holistic approach is needed when treating patients with Roemheld Syndrome as both the cardiac and gastrointestinal components need to be addressed. Declarations Disclosures The authors have no conflict of interest to disclose. Authors' contributions KP wrote the original-draft and was involved in data-curation together with revision of the manuscript. CY provided supervision along with critical feedback and manuscript revision. EL was involved in supervision, along with providing critical feedback. All authors were involved in diagnostic assessment and patient management. All authors contributed to clinical interpretation, literature review and manuscript review. All authors read and approved the final manuscript. Acknowledgements Funding Sources This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Authorship All authors attest they meet the current ICMJE criteria for authorship. Ethics declarations Ethics approval and consent to participate The study protocol was carried out in accordance with Declaration of Helsinki guidelines. This case report used fully anonymized patient data. Consent for Publication Written informed consent for publication of this case report (including clinical details, imaging findings, and other relevant information) was obtained from the patient. Competing interests The authors declare no competing interests. References Yokokawa M, Good E, Chugh A, Pelosi F, Crawford T, Krit Jongnarangsin, et al. Intramural Idiopathic Ventricular Arrhythmias Originating in the Intraventricular Septum. Circulation Arrhythmia Electrophysiol. 2012;5(2):258–63. Briceño DF, Enriquez A, Liang JJ, Shirai Y, Santangeli P, Guandalini G et al. Septal Coronary Venous Mapping to Guide Substrate Characterization and Ablation of Intramural Septal Ventricular Arrhythmia. JACC Clinical electrophysiology [Internet]. 2019;5(7):789–800. Available from: https://www.sciencedirect.com/science/article/pii/S2405500X1930307X Ghannam M, Liang J, Sharaf-Dabbagh G, Latchamsetty R, Jongnarangsin K, Morady F et al. Mapping and Ablation of Intramural Ventricular Arrhythmias: A Stepwise Approach Focused on the Site of Origin. JACC Clinical electrophysiology [Internet]. 2020;6(11):1339–48. Available from: https://pubmed.ncbi.nlm.nih.gov/33121661/ Liang JJ, Bogun F. Coronary Venous Mapping and Catheter Ablation for Ventricular Arrhythmias. Methodist DeBakey Cardiovascular Journal [Internet]. 2021 Jan 1 [cited 2026 Jan 7];17(1):13. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC8158455/ Hanson M, Peters C, Enriquez A, Garcia F. Cardiac venous system mapping for ventricular arrhythmia localization. Heart Rhythm O2. 2025;6(1):70–7. Kawata H, Yamada T, Karanam S, Reddy R. Intracoronary artery mapping and 3-dimensional visualization of the coronary arteries with a 0.014 inch guidewire in catheter ablation of left ventricular summit premature ventricular contractions. HeartRhythm Case Reports [Internet]. 2020;6(12):914–7. Available from: https://www.sciencedirect.com/science/article/pii/S2214027120301986 Katagiri T, Nguyen MT, Yamamoto T, Fujimura T, Kajiwara M, Hirooka Y et al. Ethanol Ablation of Refractory Premature Ventricular Complex Originating from a Left Ventricular Summit Communicating Vein after Radiofrequency Catheter Ablation Failed in a Dilated Cardiomyopathy Patient. Internal medicine (Tokyo, Japan) [Internet]. 2025 Autumn;64(4):563–7. Available from: https://pubmed.ncbi.nlm.nih.gov/38987189/ Meier D, Pavon A, Pascale P et al. Ablation of Incessant Premature Ventricular Complex Through Retrograde Transvenous Ethanol Infusion. J Am Coll Cardiol Case Rep 2020 Jun, 2 (6) 973–8. https://doi.org/10.1016/j.jaccas.2020.01.032 Bennett R, Campbell T, Byth K, et al. Catheter Ablation Using Half-Normal Saline and Dextrose Irrigation in an Ovine Ventricular Model. J Am Coll Cardiol EP. 2021 Oct;7(10):1229–39. https://doi.org/10.1016/j.jacep.2021.05.002 . Ikenouchi T, Takigawa M, Goya M, Yamaguchi J, Martin CA, Yamamoto T et al. The effect of half-normal saline irrigation on lesion characteristics in temperature-flow-controlled ablation. Journal of interventional cardiac electrophysiology: an international journal of arrhythmias and pacing [Internet]. 2024;67(6):1331–40. Available from: https://pubmed.ncbi.nlm.nih.gov/37946002/ Enriquez A, Neira V, Bakker D, Baley J, Bisleri G, Baranchuk A et al. Bipolar ablation with half normal saline for deep intramural outflow tract premature ventricular contraction. HeartRhythm Case Reports [Internet]. 2019 Aug [cited 2026 Jan 10];5(8):436–9. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6701005/ Berte B, Cochet H, Magat J, Naulin J, Ghidoli D, Pillois X et al. Irrigated Needle Ablation Creates Larger and More Transmural Ventricular Lesions Compared With Standard Unipolar Ablation in an Ovine Model. Circulation Arrhythmia and electrophysiology [Internet]. 2015;8(6):1498–506. Available from: https://pubmed.ncbi.nlm.nih.gov/26359480/ Mathis BJ, Suzuki R, Kuroda Y, Kato H, Hiramatsu Y. Understanding the Gut-Heart Axis in Roemheld Syndrome: Mechanisms and Clinical Insights. Encyclopedia. 2024;4(4):1721–38. Breit S, Kupferberg A, Rogler G, Hasler G. Vagus Nerve as Modulator of the Brain–Gut Axis in Psychiatric and Inflammatory Disorders. Front Psychiatry. 2018;9(44). Additional Declarations No competing interests reported. Supplementary Files OmnipolarSparkle.mpg OmnipolarPropagationwOT.mpg GuidewireMapping.mpg CoronarySinusSeptalVenousBranchWire.avi CoronarySinusSeptalVenousBranchVenogram.avi Cite Share Download PDF Status: Posted Version 1 posted 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-8752849","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":588041814,"identity":"bd4467cc-27f7-4e9c-85b5-30cf7fa47768","order_by":0,"name":"Kunaraj Perumalu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYBACCQjFxsPP3gCkDSyI1yIj2XMApEWCaC0MNgY3EpD5eIDkjNyDnytq+HgMbj6/uuFHgQQDf3t3Al4t0hJ5yZJnjrHxSN7OKbvZA3SYxJmzG/BqkZPIMZBsYGPj4budk3aDB6jFQCKXoBbjnw3/2HgYbp5Ju/mHGC3SEjlmko1tbDwCN9iP3SbKFsmeN2aWjX1Av/TksN2WMZDgIegXieM5xjcbvh2z52c//uzmmz82cvztvfi1QMExIOYxALF4iFEOAjVAzP6AWNWjYBSMglEwwgAACiBCwYmof7QAAAAASUVORK5CYII=","orcid":"","institution":"National Heart Centre Singapore","correspondingAuthor":true,"prefix":"","firstName":"Kunaraj","middleName":"","lastName":"Perumalu","suffix":""},{"id":588041815,"identity":"998702ca-6acb-46e4-99b7-dd598c0b9d9b","order_by":1,"name":"Colin Yeo","email":"","orcid":"","institution":"Changi General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Colin","middleName":"","lastName":"Yeo","suffix":""},{"id":588041816,"identity":"2c8ee47b-2e02-46c9-9305-f1dee5fd3854","order_by":2,"name":"Eric Tien Siang Lim","email":"","orcid":"","institution":"National Heart Centre Singapore","correspondingAuthor":false,"prefix":"","firstName":"Eric","middleName":"Tien Siang","lastName":"Lim","suffix":""}],"badges":[],"createdAt":"2026-01-31 23:23:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8752849/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8752849/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102438534,"identity":"a931fd5a-0d18-4c01-bda0-73e00d2e77bd","added_by":"auto","created_at":"2026-02-11 16:34:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":3924254,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(A).\u003c/strong\u003e 12-lead electrocardiogram showing narrow QRS PVC with probability of septal origin. \u003cstrong\u003e(B). \u003c/strong\u003e12-lead surface electrocardiogram shows absence of notching in inferior leads, with earlier transition at V3 and more negative QRS at lead aVL than aVR. \u003cstrong\u003e(C)\u003c/strong\u003e. Earliest electrogram signal on high density mapping catheter on-time at basal right ventricular septum\u003cstrong\u003e (D). \u003c/strong\u003eEarliest electrogram signal being late at basal left ventricular septum compared to right ventricular septum.\u003c/p\u003e","description":"","filename":"IMPVCFigure1.png","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/0ca62d5712346622b78d9ab1.png"},{"id":102438537,"identity":"b177464e-b813-4d30-80f8-398941ef5f8f","added_by":"auto","created_at":"2026-02-11 16:34:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":3881589,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(A).\u003c/strong\u003e Biotronik VisionWire mapping showed earliest electrogram signal at the septal venous branch by 20ms. \u003cstrong\u003e(B). \u003c/strong\u003ePace match from basal right ventricular septum was 64% with no other areas showing better pace match (indicating transmurality). \u003cstrong\u003e(C) \u003c/strong\u003eRadiofrequency catheter ablation using half-normal saline at basal right ventricular septum led to acceleration with no further PVC inducibility.\u003cstrong\u003e(D). \u003c/strong\u003e12-lead surface electrocardiogram showing no PVCs post ablation.\u003c/p\u003e","description":"","filename":"IMPVCFigure2.png","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/7787fdcb98bc088fbc981847.png"},{"id":102438540,"identity":"edc496e4-d16d-47ca-944f-2848cb60550b","added_by":"auto","created_at":"2026-02-11 16:34:33","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":3734882,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(A).\u003c/strong\u003e Advisor\u003csup\u003eTM\u003c/sup\u003e HD Grid mapping catheter placed at the basal right ventricle corresponding to the earliest PVC which was on-time. Contrast venogram showing the septal venous perforator branch of the anterior interventricular vein that is closest to the HD grid mapping catheter. \u003cstrong\u003e(B).\u003c/strong\u003e Biotronik Vision Guidewire cannulated in the septal perforator branch of interest showed the earliest activation by 20ms. \u003cstrong\u003e(C). \u003c/strong\u003eRadiofrequency ablation from basal right ventricle which triggered response and led to suppression of PVCs.\u003c/p\u003e","description":"","filename":"IMPVCFigure3.png","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/e06660879a5c265c6a4fc1c7.png"},{"id":102438542,"identity":"1c7c73f3-b7a1-4776-9702-3526dcfd716d","added_by":"auto","created_at":"2026-02-11 16:34:33","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":12900238,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(A).\u003c/strong\u003e Advisor\u003csup\u003eTM \u003c/sup\u003eHD Grid mapping of basal right ventricle showing earliest local activation on-time at right ventricular septum. \u003cstrong\u003e(B). \u003c/strong\u003eAdvisor\u003csup\u003eTM \u003c/sup\u003eHD Grid mapping of basal left ventricle showing earliest local activation late by 5ms than at right ventricular septum. \u003cstrong\u003e(C) \u003c/strong\u003eBiotronik VisionWire (0.014-inch) mapping showing the septal perforator branch being the earliest by 20ms compared to both ventricular chambers\u003cstrong\u003e (D). \u003c/strong\u003eRadiofrequency catheter ablation catheter distance being 11mm from the earliest PVC breakout site at septal venous perforator branch.\u003c/p\u003e","description":"","filename":"IMPVCFigure4.png","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/fe939d817ca1b522e541f31c.png"},{"id":104401688,"identity":"07636473-eb11-487b-9d62-c51dfd59244b","added_by":"auto","created_at":"2026-03-11 12:13:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":23142962,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/0b213264-cb01-45e3-bc26-302888658a01.pdf"},{"id":102745535,"identity":"d5aeb3c8-38e8-43b6-b8a6-67e5ea8eae1a","added_by":"auto","created_at":"2026-02-16 08:51:32","extension":"mpg","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":4368098,"visible":true,"origin":"","legend":"","description":"","filename":"OmnipolarSparkle.mpg","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/ba4778bca0343cf92a5e5386.mpg"},{"id":102438538,"identity":"a8e5fc84-c982-4856-9210-f12b75a5b79f","added_by":"auto","created_at":"2026-02-11 16:34:33","extension":"mpg","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":4120604,"visible":true,"origin":"","legend":"","description":"","filename":"OmnipolarPropagationwOT.mpg","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/30f73f7e7e529f122f7231df.mpg"},{"id":102746179,"identity":"209835e0-266d-4b57-86a9-1f16bf46ce53","added_by":"auto","created_at":"2026-02-16 08:56:01","extension":"mpg","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":7342452,"visible":true,"origin":"","legend":"","description":"","filename":"GuidewireMapping.mpg","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/eefacadf8f232321a93bb90e.mpg"},{"id":102745892,"identity":"4663d776-52c0-4dce-88bd-7df208fcbee5","added_by":"auto","created_at":"2026-02-16 08:54:34","extension":"avi","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":305664,"visible":true,"origin":"","legend":"","description":"","filename":"CoronarySinusSeptalVenousBranchWire.avi","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/e703e996bb62c591daa2577c.avi"},{"id":102745895,"identity":"b3ecfaf7-1814-4adb-8540-266963c67809","added_by":"auto","created_at":"2026-02-16 08:54:34","extension":"avi","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":1634304,"visible":true,"origin":"","legend":"","description":"","filename":"CoronarySinusSeptalVenousBranchVenogram.avi","url":"https://assets-eu.researchsquare.com/files/rs-8752849/v1/45bb2bfebd2353d0ce926c7f.avi"}],"financialInterests":"No competing interests reported.","formattedTitle":"Guidewire-Assisted 3D Mapping of Intramural Ventricular Arrhythmia Associated with Roemheld Syndrome: A Novel Case Report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIntramural PVCs originate in the interventricular septum or deep septal regions. Standard mapping and ablation catheters typically only reach the endocardial or epicardial surfaces, leaving intramural foci inaccessible for direct contact. Therefore, utilizing mapping guidewires helps delineate the origin of PVCs and simultaneously determines the appropriate approach to catheter ablation. Roemheld syndrome can be associated with PVCs due to a vagus nerve-mediated reflex triggered by gastrointestinal pressure.\u003c/p\u003e"},{"header":"Case History","content":"\u003cp\u003eA 45-year-old lady with no known co-morbids presented with frequent palpitations triggered by abdominal pain for 1 month. A 12-lead surface electrocardiogram and 24-hour Holter study showed non-outflow tract premature ventricular complexes with a burden of 24%. Her symptoms persisted despite being on oral bisoprolol. Her transthoracic echocardiogram and cardiac MRI showed preserved left ventricular ejection fraction with no evidence of structural heart disease or myocardial fibrosis. She underwent electrophysiology study and 3D electroanatomical mapping using Ensite X EP system. Two femoral vein punctures and one femoral artery puncture was done via modified Seldinger technique. Coronary sinus cannulation with SL-2 sheath support and an Advisor\u0026trade; HD Grid was used to map RVOT (right ventricle outflow tract), right ventricle and the left ventricle. Local activation time (LAT) mapping showed consistent earliest premature ventricular complexes breakout site which was on time at the right ventricular septum. The LAT map demonstrated two discrete sites of premature ventricular complexes origin (from both superior and inferior right ventricular septum). Therefore, the left ventricle was mapped via retrograde aortic approach. The earliest breakout site from left ventricular septum was 5ms later than right ventricular septum.\u003c/p\u003e \u003cp\u003eBased on the information obtained from both ventricular chambers, decision was made to map coronary sinus tributaries especially anterior interventricular vein using Biotronik VisionWire (0.014inch). A diagnostic multipurpose coronary catheter was used for support and ease accessibility of the vision wire further into septal branches. The earliest unipolar signal recorded at the septal perforator branch of coronary venous system was the earliest by 20ms. This coincides with the location of one of the septal perforator branches which was earlier captured via a coronary venous system venography. Therefore, combination of right ventricular, left ventricular and coronary venous system maps showed the premature ventricular complexes to be intramural in origin. Radiofrequency catheter ablation using half-normal saline (0.45% NaCl) was performed at the basal right ventricular septum.\u003c/p\u003e \u003cp\u003eAn energy of 35W to 40W was delivered for 60 seconds, with half normal saline irrigation and additional consolidation lesions. It led to acceleration of clinical premature ventricular complexes and their subsequent suppression with no further recurrences. Acute procedural success was achieved with non-inducibility of further clinical premature ventricular complexes.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis case highlights the importance of multimodality tools in accurately locating the origin of intramural PVCs. Based on existing literature, intramural PVCs ablation can be challenging due to the risk of recurrences despite acutely successful ablation. The important considerations to look into, in cases of suspected intramural PVCs will be to compare the earliest activation time from different chambers of the heart whereby there will be significant borderline discrepancy in the activation time (neither late nor early).\u003c/p\u003e \u003cp\u003e \u003csup\u003e1\u003c/sup\u003eThe 12-lead surface electrocardiogram does provide adequate clue on the probability of a septal PVC origin which is absence of notching in inferior leads, narrow QRS pattern with earlier transition at V3 and more negative QRS at lead aVL than aVR.\u003c/p\u003e \u003cp\u003eIn our case, mapping the adjacent structures of the earliest exit site is important to appreciate the best approach. Mapping of both sides of the interventricular septum with isochronal LAT revealed that neither sides were truly early. This suggests that the endocardial surfaces are only the exit sites. Ablation of only the exit sites may not modify the substrate. This is a clue suggesting PVC origin from deep septal or intramural. This can be approached in different ways during 3D electroanatomical mapping and radiofrequency catheter ablation.\u003c/p\u003e \u003cp\u003e \u003csup\u003e2,3\u003c/sup\u003eThe coronary venous system should be further mapped in cases of suspected intramural PVCs, to identify the site of earliest activation. In our case, coronary sinus mapping focused on the anterior interventricular vein and its tributaries. \u003csup\u003e4,5\u003c/sup\u003eThese were mapped using a 0.014-inch VisionWire in a unipolar configuration, which allowed for detailed anatomical reconstruction by reaching deep, small branches inaccessible to standard catheters. However, mapping via the venous system is only feasible if the area of interest is adjacent to the venous branches.\u003c/p\u003e \u003cp\u003e \u003csup\u003e6\u003c/sup\u003eThe 3D electroanatomical mapping of septal perforator branches of the coronary venous system is an important approach in cases of interventricular septum PVCs as it will guide endocardial ablation on the exact site to be targeted. \u003csup\u003e7,8\u003c/sup\u003eAn alternative bail-out strategy for reaching areas inaccessible to standard ablation catheters is the use of a 0.014-inch PTFE (polytetrafluoroethylene)-coated guidewire, either for direct energy delivery or to facilitate ethanol ablation.\u003c/p\u003e \u003cp\u003e \u003csup\u003e9,10\u003c/sup\u003eThere are several non-epicardial methods to choose from when treating intramural PVCs. We opted to use a low-ionic irrigant solution, specifically half-normal saline (0.45% NaCl), which is supported by existing literature for its ability to deliver deeper and larger lesions. Low ionic content in the irrigant helps create high impedance cloud around the electrode, simultaneously increasing current density at the tip-tissue interface which enables larger and deeper lesion delivery.\u003c/p\u003e \u003cp\u003e \u003csup\u003e11\u003c/sup\u003eOther options include bipolar ablation with 2 ablation catheters from opposite sides of the myocardial wall to ensure adequate transmural lesions, or unipolar ablation at multiple adjacent sites to mitigate the heat-sink effect and achieve a better clinical endpoint. \u003csup\u003e12\u003c/sup\u003eIrrigated needle ablation catheter is also possible to create intramural lesions, but it is not readily available in most centres.\u003c/p\u003e \u003cp\u003e \u003csup\u003e13\u003c/sup\u003eTo our knowledge, this is the first case report describing intramural PVCs associated with Roemheld syndrome. To the best of our knowledge, no large-scale studies have been published on this specific topic to date. A complex gut-brain-heart triad, linked primarily by the vagus nerve, may contribute to this phenomenon. This mechanism is attributed to autonomic imbalance caused by compensatory sympathetic activity and the subsequent release of catecholamines. \u003csup\u003e14\u003c/sup\u003ePro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 increase transmural dispersion of repolarization, creating an electrophysiological substrate that may potentially promote intramural PVCs.\u003c/p\u003e \u003cp\u003eIntramural PVCs are considered challenging because of the potential for future recurrence. Therefore, comprehensive strategies in mapping and catheter ablation can be deployed to achieve a good clinical endpoint.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe use of coronary venous system guidewire mapping as an alternative to the epicardial approach is essential in areas inaccessible by standard mapping or ablation catheters. Mapping with coronary wires such as the Biotronik Vision wire allows us to map the small branches which are otherwise not accessible with even the smallest calibre diagnostic EP catheter. A holistic approach is needed when treating patients with Roemheld Syndrome as both the cardiac and gastrointestinal components need to be addressed.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDisclosures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no conflict of interest to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eKP wrote the original-draft and was involved in data-curation together with revision of the manuscript. CY provided supervision along with critical feedback and manuscript revision. EL was involved in supervision, along with providing critical feedback. All authors were involved in diagnostic assessment and patient management. All authors contributed to clinical interpretation, literature review and manuscript review. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Sources\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthorship\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors attest they meet the current ICMJE criteria for authorship.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study protocol was carried out in accordance with Declaration of Helsinki guidelines. This case report used fully anonymized patient data.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for Publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent for publication of this case report (including clinical details, imaging findings, and other relevant information) was obtained from the patient.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eYokokawa M, Good E, Chugh A, Pelosi F, Crawford T, Krit Jongnarangsin, et al. Intramural Idiopathic Ventricular Arrhythmias Originating in the Intraventricular Septum. Circulation Arrhythmia Electrophysiol. 2012;5(2):258\u0026ndash;63.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrice\u0026ntilde;o DF, Enriquez A, Liang JJ, Shirai Y, Santangeli P, Guandalini G et al. 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Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://pubmed.ncbi.nlm.nih.gov/26359480/\u003c/span\u003e\u003cspan address=\"https://pubmed.ncbi.nlm.nih.gov/26359480/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMathis BJ, Suzuki R, Kuroda Y, Kato H, Hiramatsu Y. Understanding the Gut-Heart Axis in Roemheld Syndrome: Mechanisms and Clinical Insights. Encyclopedia. 2024;4(4):1721\u0026ndash;38.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBreit S, Kupferberg A, Rogler G, Hasler G. Vagus Nerve as Modulator of the Brain\u0026ndash;Gut Axis in Psychiatric and Inflammatory Disorders. Front Psychiatry. 2018;9(44).\u003c/span\u003e\u003c/li\u003e\u003c/ol\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":"Intramural PVCs, Vision Guide Wire, Bipolar Ablation, Ethanol Infusion, Electrophysiology study, Electroanatomical mapping, Roemheld Syndrome","lastPublishedDoi":"10.21203/rs.3.rs-8752849/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8752849/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eIntramural PVCs (premature ventricular complexes) can be challenging to treat due to the deep origin within the myocardium.\u003c/p\u003e\u003ch2\u003eCase Summary\u003c/h2\u003e \u003cp\u003eA 45-year-old female with frequent palpitations triggered by abdominal pain was found to have a 24% PVC burden over 24 hours and preserved LVEF (left ventricular ejection fraction). An electrophysiology study and 3D electroanatomical mapping showed features of intramural PVCs. The coronary venous system was further mapped using VisionWire (0.014-inch). Catheter ablation at the basal right ventricular septum led to PVC suppression with non-inducibility of the clinical PVC at the end of the case.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThe use of multimodality mapping and ablation tool has enabled us to manage cases effectively with good clinical outcomes. Roemheld syndrome is an understudied diagnosis and forgotten entity that can lead to PVCs via vagus nerve mediated mechanism.\u003c/p\u003e","manuscriptTitle":"Guidewire-Assisted 3D Mapping of Intramural Ventricular Arrhythmia Associated with Roemheld Syndrome: A Novel Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-11 16:34:28","doi":"10.21203/rs.3.rs-8752849/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":"211cf1e8-4934-454a-89c2-3e5888642a5f","owner":[],"postedDate":"February 11th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-04T06:10:25+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-11 16:34:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8752849","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8752849","identity":"rs-8752849","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}
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