Aims: To determine the frequency, predictors, and outcome implications of pulmonary hypertension (PH) diagnosed by Doppler echocardiography in a large cohort of patients with the homogenous diagnosis of degenerative mitral regurgitation (MR) due to flail leaflets.
Methods and results: The Mitral Regurgitation International DAtabase (MIDA) is a registry including patients with MR due to flail leaflets consecutively referred at tertiary centres in Europe and the USA. Between 1987 and 2004, pulmonary artery systolic pressure (PASP) was measured at baseline by Doppler echocardiography in 437 patients (age 67 ± 11 years; 66% men). Pulmonary hypertension (PASP > 50 mmHg) was observed in 102 patients (23%). Independent predictors of PH were age and left atrial size (P < 0.0001). During a mean follow-up of 4.8 ± 2.8 years, PH was a strong independent predictor of death [adjusted HR 2.03 (1.30-3.18) P = 0.002], cardiovascular death [CVD; adjusted HR 2.21 (1.30-3.76) P = 0.003], and heart failure [adjusted HR 1.70 (1.10-2.62) P = 0.018]. Mitral valve surgery at any time during follow-up (performed in 325 patients, 75%) was beneficial [adjusted HR for death 0.22 (0.14-0.36) P < 0.001], but PH was associated with the increased risk of postoperative death and CVD (P = 0.01).
Conclusion: Pulmonary hypertension is a frequent complication of significant MR due to flail leaflet and is associated with major outcome implications, approximately doubling the risk of death and heart failure after diagnosis. Mitral valve surgery performed during follow-up is beneficial but does not completely abolish the adverse effects of PH once it is established and is particularly beneficial in patients without PH. These data support relieving PH secondary to MR due to flail leaflet, but also careful consideration for mitral surgery before PH is established.