Longitudinal Assessment of TAPSE/PASP Ratio and Its Correlation with Clinical Outcomes in Pulmonary Arterial Hypertension.

BACKGROUND: The aim of this study was to assess the prognostic significance of the longitudinal tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio as a surrogate marker of right ventricular (RV) to pulmonary arterial (PA) coupling in patients with pulmonary arterial hypertension (PAH). METHODS: A retrospective cohort study was conducted on patients with PAH. The TAPSE/PASP ratio at baseline and at 3 to 6 months of follow-up was evaluated along with other echocardiographic and clinical parameters. RESULTS: The study included 68 patients with PAH, 75% of whom were female, with a mean age of 46 years and a mean follow-up duration of 64 months. At baseline, non-survivors had higher brain natriuretic peptide levels, shorter 6-minute walk distance (6MWD), and worse hemodynamic profiles compared with survivors. A TAPSE/PASP ratio > 0.22 mm/mmHg at baseline and > 0.23 mm/mmHg at 3 to 6 months of follow-up was associated with improved survival. Compared with baseline, survivors had lower pulmonary vascular resistance, lower PASP, and reduced left ventricular eccentricity indexat follow-up. In addition, better outcomes were observed in patients with World Health Organization functional class (WHO FC) I/II and 6MWD > 390 m compared with those in WHO FC III/IV and 6MWD ≤ 390 m. CONCLUSIONS: The TAPSE/PASP ratio is a noninvasive marker of RV-PA coupling that can provide dynamic prognostic insights in patients with PAH. It may assist in guiding treatment escalation and individualized therapy. Further studies are needed to verify its role and integration into comprehensive PAH risk assessment frameworks.