Noninvasive Assessment of Hemodynamic Status in HeartWare Left Ventricular Assist Device Patients: Validation of an Echocardiographic Approach

Abstract

Objectives: The aim of this prospective study was to validate an echocardiographic protocol derived from 5 HeartWare left ventricular assist device (HVAD) patients for the noninvasive evaluation of right atrial pressure (RAP) and left atrial pressure (LAP) in HVAD patients.

Background: Echocardiography is an invaluable tool to optimize medical treatment and pump settings and also for troubleshooting residual heart failure. Little is known about the echocardiographic evaluation of hemodynamic status in HVAD patients.

Methods: Right heart catheterization and Doppler echocardiography were performed in 35 HVAD patients. Echocardiography-estimated RAP (eRAP) was assessed using inferior vena cava diameter, hepatic venous flow analysis, and tricuspid E/e' ratio. Echocardiography-estimated LAP was assessed using E/A ratio, mitral E/e' ratio, and deceleration time.

Results: eRAP and estimated LAP significantly correlated with invasive RAP and LAP (respectively, r = 0.839, p < 0.001, and r = 0.889, p < 0.001) and accurately detected high RAP and high LAP (respectively, area under the curve 0.94, p < 0.001, and area under the curve 0.91, p < 0.001). High eRAP was associated with high LAP (area under the curve 0.92, p < 0.001) and correlated with death or hospitalization at 180 days (odds ratio: 8.2; 95% confidence interval: 1.1 to 21.0; p = 0.04). According to estimated LAP and eRAP, patients were categorized into 4 hemodynamic profiles. Fifteen patients (43%) showed the optimal unloading profile (normal eRAP and normal wedge pressure). This profile showed a trend toward a lower risk for adverse cardiac events at follow-up (odds ratio: 0.2; 95% confidence interval: 0.1 to 1.0; p = 0.05) compared with other hemodynamic profiles.

Conclusions: Doppler echocardiography accurately estimated hemodynamic status in HVAD patients. This algorithm reliably detected high RAP and LAP. Notably, high RAP was associated with high wedge pressure and adverse outcome. The benefit of noninvasive estimation of hemodynamic status in the clinical management of patients with left ventricular assist devices needs further evaluation.

Keywords: HVAD; echocardiography; hemodynamic assessment; left atrial pressure; left ventricular assist device.