Long-term Outcome of Cardiac Surgery in Patients With Mitral Stenosis and Severe Pulmonary Hypertension

Abstract

Background Pulmonary hypertension increases perioperative risk in patients having mitral valve replacement, but most studies have included patients with mixed mitral valve disease and have not examined long-term outcome. Methods and Results We retrospectively examined the results and predictors of outcome of cardiac surgery in 43 patients (age, 62±13 years [mean±SD]; 81% women) with a primary diagnosis of mitral stenosis and severe pulmonary hypertension (pulmonary artery systolic pressure ≥60 mm Hg or mean pressure ≥50 mm Hg). Patients with more than mild mitral regurgitation were excluded. Thirty-eight patients (88%) were in NYHA functional class III or IV, and 11 patients (26%) had an acute presentation requiring urgent surgery. Preoperative hemodynamics demonstrated a mean mitral valve area of 0.7±0.3 cm ² , mean pulmonary artery pressure of 50±9 mm Hg, and pulmonary artery systolic pressure of 81±18 mm Hg. Other characteristics included right ventricular failure (18 patients), coronary artery disease (16 patients), and critical aortic stenosis (11 patients). Forty patients underwent mitral valve replacement with St Jude prostheses; 3 had open commissurotomy. Additional surgical procedures included aortic valve replacement (42%), coronary artery bypass graft surgery (26%), and tricuspid valvuloplasty (16%). There were 5 perioperative deaths (11.6%), and 7 other patients (16%) had major complications, including reoperation for hemorrhage, stroke, respiratory failure, myocardial infarction, or a >30-day hospitalization. Univariate analysis of demographic, hemodynamic, and operative characteristics identified the following predictors of perioperative death ( P <.05): acute presentation, clinical evidence of right ventricular failure, impaired left ventricular ejection fraction, and increased left ventricular diastolic pressure. Predictors of complications ( P <.05) were acute presentation, ECG evidence of right ventricular hypertrophy, and elevated right ventricular systolic pressure. Multivariate analysis showed only acute presentation and right ventricular hypertrophy as predictors of perioperative death or major complications, respectively. Five- and 10-year actuarial survivals were 80% and 64%, respectively. The only predictor of long-term mortality was advanced age. Functional NYHA status was improved by one grade or more in 76% of survivors. Conclusions Patients referred to a tertiary care hospital in the United States with mitral stenosis and severe pulmonary hypertension often have other associated cardiac diseases and comorbid conditions. Cardiac surgery can be successfully performed with an acceptable mortality, and risk factors for poor perioperative outcome can be identified by preoperative clinical characteristics. Younger patients have the best long-term survival, and most survivors experienced long-term improvement in functional status.