Shape of the Right Ventricular Outflow Doppler Envelope and Severity of Pulmonary Hypertension

Abstract

Background: Pulmonary arterial hypertension is defined as a group of diseases characterized by a progressive increase in pulmonary vascular load, leading to a marked increase in pulmonary artery pressure (PAP). A cross-sectional descriptive study in Baghdad Teaching Hospital and Iraqi Center of Heart Disease with Duration Beginning of September 2014 to the end of August 2015. Aim: We devised a study to determine whether visual assessment of the right ventricular outflow Doppler signals can be useful in identifying the severity of pulmonary hypertension. Patients and methods: We used a pulsed Doppler technique to examine the flow velocity pattern in the RVOT in 127 patients. Inclusion criteria: All patients had a complete echocardiogram, including pulsed Doppler spectral signals across the RVOT, discernible tricuspid regurgitation signal, good endocardial border resolution of both right and left ventricular chambers for tracing of the end-systole and end-diastole, as well as M- mode of the lateral tricuspid annulus. In addition, all these patients included for the analysis were in normal sinus rhythm. Exclusion criteria: No atrial or ventricular ectopy or other cardiac arrhythmia was present at the time of the study, and none of the patients had a pacer or defibrillator wire in the right ventricle (RV). No previous cardiac surgery. Result: Visual inspection of RVOT spectral Doppler signals from the 127 showed four dynamic patterns; pulmonary artery systolic pressure (PASP) was significantly correlated with these different types of RVOT spectral Doppler signals. Both TR pressure gradient (PG) and PASP increased significantly from groups I to IV with p-value ˂ 0.05; mean pulmonary PASP was 32.92 in pattern I, 56.07 in pattern II, 73.65 in pattern III and 113.45 in pattern IV and mean TR PG was 27.57 in pattern I, 47.28 in pattern II, 64.32 in pattern. III and 102.27 in pattern IV. Furthermore, Right ventricular outflow velocity time integral (VTI), acceleration time (ACT), and pulmonary vascular resistance (PVR) showed a significant correlation with the four right ventricular outflow Doppler patterns with p-value ˂ 0.05. Conclusion: In this study, we show that easily appreciated differences in the shape or morphology of the right ventricular outflow tract Doppler signal provide rapid, powerful hemodynamic insight into the presence and severity of pulmonary hypertension