Background: Mitral regurgitation (MR) secondary to ischemic heart disease (IHD) increases during exercise. We tested the hypothesis that the same is also true for MR due to mitral valve prolapse (MVP).
Methods: Consecutive patients with asymptomatic MR of varying severity underwent exercise test on a supine bicycle with workload up to a maximum of 100 W. Echocardiographic measurements were performed at rest and at peak exercise. The study was designed to detect an effective regurgitant orifice (ERO) change of at least 10 mm² during exercise.
Results: Twenty-six patients (21 male, age 56 ± 12 years (mean ± SD)) were included. Patients had an ERO of 35 ± 23 mm² (mean ± SD) and regurgitation volume of 48 ± 38 mL (mean ± SD). In these patients, ERO remained unchanged (an increase of 2 ± 15 mm² during exercise, P = 0.6). The regurgitation volume (RVol) decreased with 11 ± 16 mL (mean ± SD), P = 0.003. When calculated for 1 minute, RVol increased during exercise (P = 0.01), but in relation to the total cardiac output it decreased significantly (P = 0.02).
Conclusion: Exercise does not increase the severity of MR due to MVP, in contrast to MR secondary to IHD. Different disease mechanisms behind these two types of MR could explain this difference.
© 2010, Wiley Periodicals, Inc.