Pulmonary hypertension is a complication in at least 23% of patients with significant mitral regurgitation due to flail leaflet, and approximately doubles the risk of death and heart failure after diagnosis.
Barbieri A, Bursi F, Grigioni F, et al. Prognostic and Therapeutic Implications of Pulmonary Hypertension Complicating Degenerative Mitral Regurgitation Due to Flail Leaflet. Eur Heart J. 2011; 32(6). https://www.ncbi.nlm.nih.gov/pubmed/20829213