Dissertation Christian K. Five

Trial lecture

Title: The fine line: Arrhythmia prevention and exercise recommendations in non-ischemic cardiomyopathies

Time: 10.15

Place: Rødt auditorium, Rikshospitalet 

Dissertation

Title: Mitral Valve Prolapse: Clinical Risk Stratification and Systemic Associations

Time: 13.15

Place: Rødt auditorium, Rikshospitalet

Summary

Mitral valve prolapse (MVP) is usually a benign condition, yet a minority of patients developed severe ventricular arrhythmias that may lead to syncope or, rarely, sudden cardiac death. This thesis examined clinical markers, electrophysiological features, lifestyle factors, and systemic associations that may influence arrhythmic risk in MVP.

The overall aim was to assess factors related to ventricular arrhythmias by reviewing clinical records, performing structured assessments, and analysing imaging, Holter data, and exercise testing.

Lifetime exercise dose was not associated with severe ventricular arrhythmic events, and exercise exposure did not correlate with established risk factors for severe ventricular arrhythmias. In contrast, non-sustained ventricular tachycardia during exercise stress testing was associated with later severe arrhythmias during follow-up.

Most MVP patients exhibited an increased burden of premature ventricular complexes at higher heart rates, suggesting an adrenergic component. However, PVC profile was not independently associated with severe arrhythmic outcomes. A separate analysis of patients with keratoconus found no increased prevalence of MVP, contradicting earlier reports of a shared mechanism.

Despite methodological limitations, the findings suggested that while cumulative exercise was safe, elevated heart rate may act as an acute arrhythmic trigger in susceptible individuals. Exercise stress testing may therefore be a useful adjunct tool for risk stratification.

Overall, the thesis contributed to improved understanding of arrhythmic mechanisms in MVP and highlighted the need for larger prospective studies.