Partial Pericardial Agenesis Presenting with Positional Palpitations

Partial Pericardial Agenesis Presenting with Positional Palpitations | 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 Partial Pericardial Agenesis Presenting with Positional Palpitations Francisco Alberto Rodrigues Santos¹, João Gouveia Fiuza¹, José Miguel Pais Correia¹, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9003917/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 12 You are reading this latest preprint version Abstract Background: Congenital pericardial agenesis is a rare anomaly caused by defective development of the pleuropericardial membrane. Most cases remain clinically silent, but partial defects may predispose to myocardial herniation, coronary compression, or ventricular arrhythmias. Symptomatic presentations are heterogeneous and often non-specific, which contributes to diagnostic delay. Case Presentation: We report the case of a 40-year-old man presenting with intermittent palpitations unrelated to exertion and aggravated by the left lateral decubitus position. Past medical history was unremarkable and patient did not take any chronic medication. Physical examination and laboratory studies, including thyroid function, were innocent. Initial electrocardiography revealed sinus bradycardia with incomplete right bundle branch block and left anterior fascicular block. A 24-hour Holter showed rare polymorphic premature ventricular contractions, and a treadmill stress test was normal. Transthoracic echocardiography demonstrated hypermobility of the apicolateral left ventricular segments and abnormal motion of the right ventricular apex, raising suspicion of pericardial absence. Cardiac magnetic resonance imaging confirmed partial pericardial agenesis involving the apical third of the right ventricular free wall and the apical region of the left ventricle, with reduced systolic excursion and diastolic bulging suggestive of early herniation. No evidence of coronary compression or myocardial ischemia was identified. Given the mild symptom burden and absence of complications, a conservative management plan was adopted. Surveillance consisted of periodic Holter monitoring to assess ventricular ectopy and annual echocardiography to detect potential progression of herniation or development of coronary compression. The patient remains clinically stable with infrequent palpitations and no imaging progression over follow-up. Conclusion: This case illustrates an unusual presentation of partial pericardial agenesis manifesting primarily as positional palpitations. Partial defects may confer a risk of myocardial ischemia or coronary compression and therefore warrant structured long-term monitoring even in minimally symptomatic individuals. Symptom-oriented management, Holter evaluation of ventricular ectopy, and serial imaging are essential to detect evolving herniation or coronary compromise. Increased awareness of this rare entity may facilitate earlier recognition and prevent misdiagnosis. Pericardial agenesis Partial pericardial defect Cardiac herniation Ventricular hypermobility Palpitations Cardiac MRI Congenital heart disease. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Background Congenital pericardial agenesis is an uncommon anomaly with an estimated prevalence of 1 in 10,000 individuals and is more frequent in males. It arises from incomplete fusion of the pleuropericardial membranes during embryogenesis ( 1 ). While complete agenesis typically follows a benign course, partial defects may lead to myocardial herniation, coronary artery compression, and ventricular arrhythmias due to localized cardiac hypermobility ( 2 ). While often asymptomatic, clinical presentation in symptomatic patients is heterogeneous and non-specific. Imaging, particularly cardiac MRI, plays a crucial role in diagnosis and risk stratification. Treatment must be considered on an individual basis, according to symptoms, complications and imaging findings. Conservative management is frequently the initial approach, especially with low symptom burden, while surgical intervention may be indicated in the presence of herniation, vascular narrowing or severe symptoms ( 3 ). Case Report A 40-year-old man presented with intermittent palpitations that worsened in the left lateral decubitus position. He denied chest pain, dyspnoea, dizziness, syncope or exercise intolerance. Past history included previously treated pulmonary tuberculosis and episodic vertigo. No regular medication or relevant family history. Physical examination and laboratory tests were unremarkable. ECG showed sinus bradycardia at 41 bpm with incomplete right bundle branch block and left anterior fascicular block, with left axis deviation (-40º) (Fig. 1). A 24-hour Holter revealed frequent polymorphic premature ventricular complex (PVC) (Fig. 2) and a treadmill stress test was normal-range. Transthoracic echocardiography demonstrated apicolateral left ventricular hypermobility and abnormal right ventricular apical motion, suspicious for pericardial absence (Fig. 3). Cardiac MRI confirmed partial pericardial agenesis ( 4 ), involving the apical third of the right ventricular free wall and apical left ventricle, with reduced systolic excursion (Fig. 4) and diastolic bulging consistent with early herniation (Fig. 5). No interposition of lung tissue was seen in the mediastinum (Fig. 6) ( 5 ). No coronary compression was seen. Given the mild symptoms and absence of complications, a conservative management was chosen. Follow-up included periodic Holter monitoring and annual echocardiography. The patient remains stable with infrequent palpitations and no progression of imaging abnormalities. Discussion and Conclusion Partial pericardial agenesis is rare and often difficult to diagnose due to its nonspecific symptoms. Palpitations, as seen in this case, are a less common presentation but may occur due to increased regional cardiac mobility or traction on the myocardium within the defect. Imaging modalities are pivotal in identifying this uncommon condition, due to its heterogeneous clinical manifestations ( 1 ). Partial defects carry a recognized risk of myocardial or vascular entrapment, particularly in apical or lateral segments where hypermobility is greatest, that may lead to myocardial herniation and coronary artery compression ( 1 , 4 ). Management is primarily symptom-directed, where beta-blockade might be necessary to diminish ventricular automaticity. Surgical intervention is reserved for cases with significant herniation, coronary compression or persistent severe symptoms. In minimally symptomatic patients, structured surveillance is essential. Holter monitoring is important to evaluate for ventricular ectopy, while serial echocardiography or MRI helps assess changes in herniation or emerging coronary compromise ( 1 , 5 ). This case underscores the need for heightened clinical awareness of partial pericardial agenesis, particularly when encountering positional palpitations or unexplained ventricular hypermobility on imaging. Conservative management with vigilant follow-up remains the cornerstone of care ( 2 ). Abbreviations ECG Electrocardiogram MRI Magnetic Resonance Imaging PVC Premature Ventricular Complex RV Right Ventricle LV Left Ventricle BPM Beats Per Minute Declarations Ethics approval and consent to participate Ethical approval was not required for this study, since it’s a case report. Written informed consent was obtained from the patient for participation. Consent for publication Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Availability of data and materials All data relevant to the case are included in the article. No additional datasets were generated or analysed. Competing interests The authors declare that they have no competing interests. Funding The authors received no specific funding for this work. Authors’ contributions I.F.P contributed to patient management and data acquisition. F.R.S analysed and interpreted the data. J.M.S And J.G.F drafted the manuscript. J.M.P.C. acquired and selected the figures. All authors critically revised the manuscript and approved the final version. Acknowledgements Not applicable. References Jafari F, Taheri M, Ebrahimi P, Soflaee M, Rafie RA, Anafje M. Congenital unilateral pericardial agenesis presenting as an isolated chest pain in an adolescent: a case report and comprehensive review . J Cardiothorac Surg. 2025 Dec 1;20(1). Marzullo R, Capestro A, Cosimo R, Fogante M, Aprile A, Balardi L, et al. Congenital Absence of Pericardium: The Swinging Heart . J Imaging. 2024 Aug 1;10(8). Patel AK, Gharai LR. Pericardial agenesis . Int J Cardiovasc Imaging. 2025 Oct 1;41(10):2049–51. Bersali A, Nabi F. Partial Pericardial Agenesis . Methodist Debakey Cardiovasc J. 2023;19(3):108–10. Bassareo PP, Secinaro A, Ciliberti P, Chessa M, Perrone MA, Walsh KP, et al. Congenital Absence of Pericardium: The Largest Systematic Review in the Field on 247 Worldwide Cases (1977-Now) . Congenit Heart Dis. 2023;18:595–610. Additional Declarations Competing interest reported. The authors declare that they have no financial or non-financial competing interests related to this manuscript. Supplementary Files Video1TransthoracicechocardiographyApical4C.mp4 Video2TransthoracicechocardiographyPLAX.mp4 Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 05 May, 2026 Reviews received at journal 04 May, 2026 Reviewers agreed at journal 03 May, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviews received at journal 30 Mar, 2026 Reviewers agreed at journal 22 Mar, 2026 Reviewers invited by journal 12 Mar, 2026 Editor invited by journal 03 Mar, 2026 Editor assigned by journal 03 Mar, 2026 Submission checks completed at journal 03 Mar, 2026 First submitted to journal 01 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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The authors declare that they have no financial or non-financial competing interests related to this manuscript.","formattedTitle":"Partial Pericardial Agenesis Presenting with Positional Palpitations","fulltext":[{"header":"Background","content":"\u003cp\u003eCongenital pericardial agenesis is an uncommon anomaly with an estimated prevalence of 1 in 10,000 individuals and is more frequent in males. It arises from incomplete fusion of the pleuropericardial membranes during embryogenesis (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). While complete agenesis typically follows a benign course, partial defects may lead to myocardial herniation, coronary artery compression, and ventricular arrhythmias due to localized cardiac hypermobility (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). While often asymptomatic, clinical presentation in symptomatic patients is heterogeneous and non-specific. Imaging, particularly cardiac MRI, plays a crucial role in diagnosis and risk stratification. Treatment must be considered on an individual basis, according to symptoms, complications and imaging findings. Conservative management is frequently the initial approach, especially with low symptom burden, while surgical intervention may be indicated in the presence of herniation, vascular narrowing or severe symptoms (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e"},{"header":"Case Report","content":"\u003cp\u003eA 40-year-old man presented with intermittent palpitations that worsened in the left lateral decubitus position. He denied chest pain, dyspnoea, dizziness, syncope or exercise intolerance. Past history included previously treated pulmonary tuberculosis and episodic vertigo. No regular medication or relevant family history. Physical examination and laboratory tests were unremarkable. ECG showed sinus bradycardia at 41 bpm with incomplete right bundle branch block and left anterior fascicular block, with left axis deviation (-40\u0026ordm;) (Fig.\u0026nbsp;1). A 24-hour Holter revealed frequent polymorphic premature ventricular complex (PVC) (Fig.\u0026nbsp;2) and a treadmill stress test was normal-range. Transthoracic echocardiography demonstrated apicolateral left ventricular hypermobility and abnormal right ventricular apical motion, suspicious for pericardial absence (Fig.\u0026nbsp;3). Cardiac MRI confirmed partial pericardial agenesis (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e), involving the apical third of the right ventricular free wall and apical left ventricle, with reduced systolic excursion (Fig.\u0026nbsp;4) and diastolic bulging consistent with early herniation (Fig.\u0026nbsp;5). No interposition of lung tissue was seen in the mediastinum (Fig.\u0026nbsp;6) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). No coronary compression was seen.\u003c/p\u003e \u003cp\u003eGiven the mild symptoms and absence of complications, a conservative management was chosen. Follow-up included periodic Holter monitoring and annual echocardiography. The patient remains stable with infrequent palpitations and no progression of imaging abnormalities.\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion and Conclusion","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003cp\u003ePartial pericardial agenesis is rare and often difficult to diagnose due to its nonspecific symptoms. Palpitations, as seen in this case, are a less common presentation but may occur due to increased regional cardiac mobility or traction on the myocardium within the defect. Imaging modalities are pivotal in identifying this uncommon condition, due to its heterogeneous clinical manifestations (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Partial defects carry a recognized risk of myocardial or vascular entrapment, particularly in apical or lateral segments where hypermobility is greatest, that may lead to myocardial herniation and coronary artery compression (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eManagement is primarily symptom-directed, where beta-blockade might be necessary to diminish ventricular automaticity. Surgical intervention is reserved for cases with significant herniation, coronary compression or persistent severe symptoms. In minimally symptomatic patients, structured surveillance is essential. Holter monitoring is important to evaluate for ventricular ectopy, while serial echocardiography or MRI helps assess changes in herniation or emerging coronary compromise (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis case underscores the need for heightened clinical awareness of partial pericardial agenesis, particularly when encountering positional palpitations or unexplained ventricular hypermobility on imaging. Conservative management with vigilant follow-up remains the cornerstone of care (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eECG\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eElectrocardiogram\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic Resonance Imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePVC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePremature Ventricular Complex\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eRV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eRight Ventricle\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLeft Ventricle\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBPM\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBeats Per Minute\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was not required for this study, since it\u0026rsquo;s a case report. Written informed consent was obtained from the patient for participation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data relevant to the case are included in the article. No additional datasets were generated or analysed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors received no specific funding for this work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eI.F.P contributed to patient management and data acquisition.\u003c/p\u003e\n\u003cp\u003eF.R.S analysed and interpreted the data.\u003c/p\u003e\n\u003cp\u003eJ.M.S And J.G.F drafted the manuscript.\u003c/p\u003e\n\u003cp\u003eJ.M.P.C. acquired and selected the figures.\u003c/p\u003e\n\u003cp\u003eAll authors critically revised the manuscript and approved the final version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eJafari F, Taheri M, Ebrahimi P, Soflaee M, Rafie RA, Anafje M. \u003cem\u003eCongenital unilateral pericardial agenesis presenting as an isolated chest pain in an adolescent: a case report and comprehensive review\u003c/em\u003e. J Cardiothorac Surg. 2025 Dec 1;20(1).\u003c/li\u003e\n\u003cli\u003eMarzullo R, Capestro A, Cosimo R, Fogante M, Aprile A, Balardi L, et al. \u003cem\u003eCongenital Absence of Pericardium: The Swinging Heart\u003c/em\u003e. J Imaging. 2024 Aug 1;10(8).\u003c/li\u003e\n\u003cli\u003ePatel AK, Gharai LR. \u003cem\u003ePericardial agenesis\u003c/em\u003e. Int J Cardiovasc Imaging. 2025 Oct 1;41(10):2049\u0026ndash;51.\u003c/li\u003e\n\u003cli\u003eBersali A, Nabi F. \u003cem\u003ePartial Pericardial Agenesis\u003c/em\u003e. Methodist Debakey Cardiovasc J. 2023;19(3):108\u0026ndash;10.\u003c/li\u003e\n\u003cli\u003eBassareo PP, Secinaro A, Ciliberti P, Chessa M, Perrone MA, Walsh KP, et al. \u003cem\u003eCongenital Absence of Pericardium: The Largest Systematic Review in the Field on 247 Worldwide Cases (1977-Now)\u003c/em\u003e. Congenit Heart Dis. 2023;18:595\u0026ndash;610.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Pericardial agenesis, Partial pericardial defect, Cardiac herniation, Ventricular hypermobility, Palpitations, Cardiac MRI, Congenital heart disease.","lastPublishedDoi":"10.21203/rs.3.rs-9003917/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9003917/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e\u003cbr\u003e\nCongenital pericardial agenesis is a rare anomaly caused by defective development of the pleuropericardial membrane. Most cases remain clinically silent, but partial defects may predispose to myocardial herniation, coronary compression, or ventricular arrhythmias. Symptomatic presentations are heterogeneous and often non-specific, which contributes to diagnostic delay.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase Presentation:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe report the case of a 40-year-old man presenting with intermittent palpitations unrelated to exertion and aggravated by the left lateral decubitus position. Past medical history was unremarkable and patient did not take any chronic medication. Physical examination and laboratory studies, including thyroid function, were innocent.\u003c/p\u003e\n\u003cp\u003eInitial electrocardiography revealed sinus bradycardia with incomplete right bundle branch block and left anterior fascicular block. A 24-hour Holter showed rare polymorphic premature ventricular contractions, and a treadmill stress test was normal.\u003c/p\u003e\n\u003cp\u003eTransthoracic echocardiography demonstrated hypermobility of the apicolateral left ventricular segments and abnormal motion of the right ventricular apex, raising suspicion of pericardial absence. Cardiac magnetic resonance imaging confirmed partial pericardial agenesis involving the apical third of the right ventricular free wall and the apical region of the left ventricle, with reduced systolic excursion and diastolic bulging suggestive of early herniation. No evidence of coronary compression or myocardial ischemia was identified.\u003c/p\u003e\n\u003cp\u003eGiven the mild symptom burden and absence of complications, a conservative management plan was adopted. Surveillance consisted of periodic Holter monitoring to assess ventricular ectopy and annual echocardiography to detect potential progression of herniation or development of coronary compression. The patient remains clinically stable with infrequent palpitations and no imaging progression over follow-up.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e\u003cbr\u003e\nThis case illustrates an unusual presentation of partial pericardial agenesis manifesting primarily as positional palpitations. Partial defects may confer a risk of myocardial ischemia or coronary compression and therefore warrant structured long-term monitoring even in minimally symptomatic individuals. Symptom-oriented management, Holter evaluation of ventricular ectopy, and serial imaging are essential to detect evolving herniation or coronary compromise. Increased awareness of this rare entity may facilitate earlier recognition and prevent misdiagnosis.\u003c/p\u003e","manuscriptTitle":"Partial Pericardial Agenesis Presenting with Positional Palpitations","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-18 08:22:47","doi":"10.21203/rs.3.rs-9003917/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-05T18:34:56+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-04T19:41:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"226676286388120038740048606132398857640","date":"2026-05-03T19:58:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"214042388099897515631768001461403980276","date":"2026-04-29T05:34:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"6995244951408469616056674917554693184","date":"2026-04-29T04:53:59+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-30T20:14:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"129528293986122979912889119103375379042","date":"2026-03-22T17:28:11+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-12T10:24:16+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-03T15:49:38+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-03T14:24:34+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-03T14:21:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cardiovascular Disorders","date":"2026-03-01T21:17:17+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4b624c9a-412c-4072-825a-d5b7474b0314","owner":[],"postedDate":"March 18th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-05T18:34:56+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-04T19:41:01+00:00","index":46,"fulltext":""},{"type":"reviewerAgreed","content":"226676286388120038740048606132398857640","date":"2026-05-03T19:58:37+00:00","index":45,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-17T22:23:09+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-18 08:22:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9003917","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9003917","identity":"rs-9003917","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}