UNLOCKING THE POWER OF PULMONARY ARTERY ACCELERATION TIME FOR ACCURATE ESTIMATE OF SYSTOLIC PULMONARY ARTERY PRESSURE DURING TRANSTHORACIC ECHOCARDIOGRAPHY

Abstract

Background: Pulmonary hypertension (PH) is a progressive cardiovascular disorder associated with high morbidity and mortality. Right heart catheterization (RHC) remains the diagnostic gold standard in diagnosing PH but it is invasive, costly, and not widely accessible, especially in low- and middle-income countries. Echocardiographic estimation of estimated peak systolic pulmonary artery pressure (EPSPAP) traditionally relies on the peak tricuspid regurgitant velocity (TRVmax); however, this parameter is absent or technically inadequate in a substantial proportion of patients. Pulmonary artery acceleration time (PAAT) is a simple Doppler-derived measurement independent of TR, has emerged as a potential non-invasive surrogate, yet validation in local populations remains limited. Objectives: This study was aimed to investigate the correlation, diagnostic agreement, and reproducibility of PAAT compared with TRVmax-derived estimated peak systolic pulmonary artery pressure (EPSPAP) among patients underwent routine transthoracic echocardiography (TTE) in Palestine. Methods: A cross-sectional study was conducted at An-Najah National University Hospital (NNUH), enrolling 200 consecutive patients between February and May 2025. PAAT was measured in the right ventricular outflow tract (RVOT) using pulsed-wave (PW) Doppler, while EPSPAP was calculated from TRVmax according to current guidelines. Correlation and Bland–Altman agreement analyses were performed. Results: The median PAAT was 109 ms. Shorter PAAT values were observed among patients with valvular heart disease and right ventricular dysfunction. PAAT showed a moderate inverse correlation with TRVmax-derived EPSPAP (ρ = –0.49, p < 0.001). Bland–Altman analysis demonstrated a systematic overestimation (+14.6 mmHg bias) with wide limits of agreement (–8.1 to +37.3 mmHg), highlighting variability at the individual patient level. According to the sensitivity and specificity across various PAAT values from 80 ms to 130 ms in identifying PH, patients with PAAT< 80 ms predicts PH and PAAT> 130 ms excludes the presence of PH. The best optimal PAAT cutoff in identifying PH was 95 ms. Conclusions: PAAT is a practical, reproducible, and TR-independent echocardiographic parameter. While it tends to overestimate pulmonary pressures compared with TRVmax-derived values, it provides complementary diagnostic value and may help close diagnostic gaps in resource-limited settings where invasive testing or reliable TRVmax signals are lacking, facilitating earlier recognition and improved management of PH.