Mitral valve prolapse (MVP), which affects approximately 2–3% of the population, is often benign but may be associated with a higher incidence of ventricular arrhythmias (VA) and sudden cardiac death (SCD). This study aimed to highlight the incidental detection of MVP among SCD cases and to investigate the associated histopathological features. In addition, we investigated the potential risk of VA in MVP patients by assessing heart rate variability (HRV) and heart rate turbulence (HRT). In 2021, two parallel investigations were conducted: a pathological examination of 225 individuals who experienced SCD, and a clinical evaluation of 50 MVP patients using 24-hour Holter monitoring. Among the SCD cases, MVP-like mitral valve changes were identified in eight subjects, along with fibrotic changes near the valve. The clinical study group was stratified into two categories based on age, clinical characteristics, and echocardiographic findings: group A: 23 individuals under 40 years with signs of myxomatous mitral valve degeneration; group B: 27 older adults with MVP and additional cardiovascular conditions. Holter monitoring in MVP patients revealed changes in HRV and HRT, which were frequently associated with the degree of mitral regurgitation (MR). These autonomic indicators may provide insight into the elevated risk of VA among this group of patients.
