Abstract
OBJECTIVES: Pronounced mitral annular disjunction (pMAD ≥8 mm) in myxomatous mitral valve disease has been associated with ventricular arrhythmias in selected cohorts, whereas minor degrees of mural separation are frequently observed in structurally normal hearts. Its clinical relevance after mitral valve surgery remains unclear. We investigated whether pMAD is associated with postoperative symptom burden and rhythm outcomes. METHODSV: In this retrospective cohort with prospective follow-up, 246 adults undergoing mitral valve surgery for Barlow's disease were classified intraoperatively as pMAD (≥8 mm) or non-pMAD (<8 mm). The primary end point was patient-reported postoperative palpitations. Propensity score-based inverse probability weighting was applied to adjust for baseline differences. Structured follow-up in pMAD patients included transthoracic echocardiography (TTE) and 24-hour Holter monitoring. RESULTS: pMAD was present in 103 patients (41.9%). Surgery effectively reduced disjunction distance. At follow-up, palpitations were more frequent in pMAD compared with non-pMAD patients (40.8% vs 18.9%, P = .011), remaining significant after adjustment. In the pMAD follow-up cohort, atrial fibrillation prevalence decreased significantly after surgery. Holter monitoring did not demonstrate sustained malignant arrhythmias. Survival and major adverse events were comparable between groups. CONCLUSIONS: After mitral valve surgery for Barlow's disease, pMAD is independently associated with increased postoperative palpitations despite anatomical correction. This association was not accompanied by excess malignant arrhythmias or adverse clinical end points, suggesting persistent symptom susceptibility rather than overt electrical instability.