Prognostic Value of Peak Exercise Systolic Pulmonary Arterial Pressure in Asymptomatic Primary Mitral Valve Regurgitation.

ABSTRACT Background The contribution of exercise echocardiography in primary asymptomatic mitral regurgitation (MR) remains debated. We aimed to gain evidence regarding its usefulness in this setting, and investigate the prognostic value of peak exercise systolic pulmonary artery pressure (SPAP). Methods We identified 177 patients (56±13 years, 69% males) with moderate-to-severe (3+)/severe (4+) degenerative MR and preserved left ventricular ejection fraction (LVEF), in sinus rhythm, referred for a clinically indicated exercise echocardiography. Our end-point, MR-related events, was a composite of all-cause death or occurrence of symptoms, heart failure, atrial fibrillation, LVEF 50mmHg. Results At rest, effective regurgitant orifice area was 48±16mm2, regurgitant volume 74±26ml, SPAP 32±7mmHg, and MR severe in 138 patients (78%). The peak exercise SPAP was 55±10mmHg. Exercise test positivity motivated surgery in 26 patients, 11 underwent prophylactic surgery, 10 were lost to follow-up and 130 included for the outcome analysis. During a follow-up of 19±7 months, 31 MR-related events (24%) were reported. Peak exercise SPAP was predictive of outcome in univariate analysis (p=0.01) and after adjustment for age, gender, MR severity, and resting SPAP (p Conclusions Our findings support the use of exercise echocardiography for risk stratification in asymptomatic primary MR and suggest a lower peak exercise SPAP threshold (50 mmHg) than previously recommended to define the timing of intervention. Prospective studies are needed to confirm these findings.