Pulmonary hypertension and left heart function: insights from tissue Doppler imaging and myocardial performance index

Abstract

Background: As a consequence of a leftward shift of the interventricular septum and of pericardial restraint, related to the degree RV dilatation, left heart function would be influenced after pulmonary hypertension and right heart failure.

Methods and results: We enrolled 70 patients with pulmonary artery systolic pressure (PASP) more than 30 mmHg: 40 patients with PASP between 30 and 60 mmHg (Group 2), 30 patients with PASP more than 60 mmHg (Group 3). Another 70 patients with normal heart performance and PASP less than 30 mmHg served as the control group (Group 1). Myocardial performance index (MPI), isovolumic contraction time (IVCT), and isovolumic relaxation time (IVRT) were obtained by tissue Doppler imaging (TDI). PASP correlated negatively to peak systolic velocity of lateral tricuspid annulus (RV-Sm) and RVEF. The MPI of RV and LV in patients with severe pulmonary hypertension (Group 3) became higher as the result of the prolongation of IVRT. The higher E/Em (peak early-diastolic mitral-inflow velocity divided by early-diastolic velocity of mitral annulus) in pulmonary hypertension indicated diastolic dysfunction of LV. The decline of left ventricular ejection fraction, and also right ventricular ejection fraction, suggested LV systolic dysfunction after pulmonary hypertension. The LV-MPI truly reflected LV systolic and diastolic dysfunction in patients with pulmonary hypertension. In multiple linear regression analysis, LV-MPI was independently associated only with RV-MPI (Beta 0.47, P < 0.0001).

Conclusion: The result infers that the systolic and diastolic function of LV declined, following pulmonary hypertension.