Simple Doppler Method for Estimating PVR

Background: Pulmonary vascular resistance (PVR) helps distinguish isolated postcapillary pulmonary hypertension (IpcPH) from those with precapillary or mixed pulmonary hypertension (PH) where PVR >2. Most echocardiographic methods for PVR estimation rely on the tricuspid regurgitant jet or right ventricular outflow tract (RVOT) velocity time integrals, and their predictive ability declines with increasing PVR. Objective: To test the hypothesis that systolic notch timing in the RVOT Doppler envelope could help estimate PVR. Participants/Methods: 95 patients with suspected PH were studied. All had been referred for right heart catheterization and had echocardiography within 24 hours of the procedure. Early systolic notching (ESN) was defined as that occurring in the initial 50% of ejection, mid-systolic notching (MSN) at the midpoint of systole, and late-systolic notching (LSN) closer to the end of systole. Notch time (NT) was measured from onset of ejection to nadir of notch; notch more...