Pulmonary Hypertension: Insights From the Reservoir-Wave Approach

Abstract

We employed the reservoir-wave approach to analyze high-fidelity pulmonary arterial (PA) pressure and Doppler flow velocity in 11 patients with varying cardiac diseases. Our specific objectives were to (1) to characterize PA wave pattern and (2) evaluate right ventricular (RV) performance. Wave pressure was partitioned into its forward and backward components. Among patients with lower PA pressures, pressure-decreasing and flow-increasing reflected waves that assist RV ejection were detected. Among the more pulmonary hypertensive patients, pressure-increasing and flow-decreasing reflected waves that impede RV ejection were detected. The four patients with the highest PA pressures showed an early systolic deceleration in flow, which was found to coincide with reflected pressure-increasing, flow-decreasing waves. Wave work done by the RV increased with PA pressure, but expressed as a fraction of total RV work, did not change. The reservoir-wave approach may prove to be a valuable tool to characterize PA-RV interaction and evaluate RV performance.