Evaluation of Right Ventricular Function in Patients Undergoing Mitral Valve Replacement with Pulmonary Artery Systolic Pressure of more than 50 mmHg: A Prospective Analysis

Abstract

The severity of pulmonary artery hypertension affects the outcomes of patients undergoing mitral valve replacement (MVR). Speckle-tracking derived strain is a new modality for the assessment of the right ventricular (RV) function as well as the longitudinal contractile pattern. Our main objective of this study was to evaluate the right ventricular (RV) function in patients undergoing MVR with pulmonary artery systolic pressure (PASP) of more than 50 mmHg at 1 and 4 weeks postoperatively. This prospective cohort study included 40 patients with rheumatic heart disease (RHD) (mitral stenosis [MS] and mitral regurgitation [MR]) scheduled to undergo MVR between January 2022 and December 2023 in AIIMS, New Delhi. Serial 2D echocardiography, tissue Doppler imaging, as well as RV speckle-tracking echocardiography were performed, and serum brain natriuretic peptide (BNP) levels were measured during the pre-operative period, 1st week and 4th weeks postoperatively to evaluate RV function. Tricuspid annular plane systolic excursion (TAPSE) and left ventricular ejection fractions (LVEFs) were significantly lower at 1 week after surgery, compared to pre-operative levels, and reached the pre-operative values at 4 weeks after surgery. The RV fractional area change (RVFAC) at 4 weeks postoperatively significantly increased compared to 1st week and baseline values. The tricuspid valve (TV) tissue velocity in systole (S'), TV velocity in diastole (E'), RV global strain (RVGLS), and RV free wall strain (RVFWLS) at post-operative 4 weeks were lower than pre-operative values, and this difference was statistically significant. Four weeks after MVR, in adult patients with RHD (MS and MR) having PASP >50 mmHg, it was observed that deformational indices or speckle-tracking echocardiography such as RVGLS and RVFWLS predict better RV dysfunction than linear indices like TAPSE. The BNP, PASP (delta TR), right atrial volume, left atrial volume, LV internal diameter in systole, and LV internal diameter in diastole decreased significantly in these patients. RVFAC increased significantly to compensate for the loss of longitudinal function.