Pulmonary arterial systolic pressure / Acceleration Time of Pulmonary
outflow relationship to evaluate the pulmonary ventricle interaction
Abstract
Background: In pulmonary hypertension (PH), the development of
dilatation and the right ventricular failure are signs of accelerated
progression of the disease, resulting in an increased risk of cardiac
death and right ventricular failure. Even the non-invasive assessment of
the systolic blood pressure in the pulmonary artery by echocardiography
does not provide a measure of ventricle-pulmonary interaction. Some
studies showed that the potential use of echocardiography to evaluate
indirectly the pulmonary vascular resistance (PVR) and the acceleration
time of pulmonary outflow (ACTPO) could be a good, correlated, indirect
measure. Methods: We decided to use a parameter that contained
information related to pulmonary artery pressure (sPAP) and pulmonary
vascular resistance. We called it PAPs/ACTPO ratio [strength/surface
unit]/[time]. We aimed to study this parameter in apparently
healthy subjects to code the normal range. From January 2017 to December
2018, 60 normal volunteer subjects and 63 patients with systemic
scleroderma (Ssc)(60F,3M), 27 with PH and 36 without PH at
two-dimensional echocardiographic/Doppler evaluation. Results: In normal
subjects, we found a mean sPAP/ACTPO ratio of 0.26 indicative of an
optimal pulmonary arterial ventricle coupling and biventricular
function. The data derived from the analysis of the patients with Ssc
showed that those presenting pre-capillary PH at cardiac catheterization
had a sPAP/ACTPO ratio of 0.40 ± 0.05. There was a significant
correlation between sPAP/ACTPO with Walk Distance (WD) and PVR but not
with TAPSE. Interobserver variability was lower than 5%.