Pulmonary arterial hypertension in rheumatic mitral stenosis: Does it affect right ventricular function and outcome after mitral valve replacement?

Abstract

Right ventricular function affects the outcome in valvular heart disease but less is known about the relation between indices of dysfunction and outcome. Seventy patients undergoing mitral valve replacement between April 2007 and April 2008 for predominant rheumatic mitral stenosis were included in the study. Two groups were formed based on right ventricular systolic pressure (RVSP), ≤40 mmHg (group I, n=16) and >41 mmHg (group II, n=54). Right ventricle (RV) function indices were studied by echocardiography. RVSP reduced significantly in group II (P=0.0001) but not in group I. Brain natriuretic peptide (BNP) was raised in all cases and reduced significantly postoperatively. Tricuspid annular plane excursion, myocardial performance index, RV descent and tricuspid valve annular shortening (TV shortening) conformed to RV dysfunction in both groups, and did not change significantly postoperatively. Regression analysis for outcome revealed TV shortening as the only significant factor (P=0.03). Receiver operating characteristic of TV shortening and adverse outcome showed worse outcome with TV shortening of <11%. RV dysfunction was observed in all cases irrespective of RVSP. TV shortening of <11% was associated with adverse outcome. Postoperative fall in BNP levels may indicate a trend towards recovery.