Noninvasive Assessment of Pulmonary Vascular Resistance Using Doppler Tissue Imaging of the Tricuspid Annulus

Abstract

Pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) are important hemodynamic parameters in patients with advanced cardiopulmonary disease. We undertook this study to determine whether Doppler tissue imaging of the tricuspid annulus could be used to assess PAP and PVR noninvasively. We studied 50 consecutive patients with suspected chronic thromboembolic pulmonary hypertension referred to our center for evaluation. We performed preoperative transthoracic echocardiography with Doppler tissue imaging of the tricuspid annulus. All patients then underwent cardiac catheterization with invasive determination of cardiac output, PAP, and PVR. The systolic velocity of the tricuspid annulus (tS(m)) had an inverse relationship with catheterization-derived mean PAP, with a correlation coefficient of -0.493 (P = .0003). The inverse correlation of tS(m) with catheterization-derived PVR was more striking, with a correlation coefficient of -0.710 (P < .0001). Based on the data, we derived the following logarithmic regression equation: PVR = 3698 - 1227 x ln(tS(m)). Doppler tissue imaging of the lateral tricuspid annulus is a useful clinical tool that can provide a noninvasive estimate of PVR in patients with chronic thromboembolic pulmonary hypertension. In this population, decreasing values of tS(m) predicted progressively higher measurements of PVR.