Prognostic Thresholds of Pulmonary Artery Pressure and Right Ventricular Function at Echocardiography in Heart Failure

Transthoracic echocardiography of right ventricular (RV) to pulmonary artery coupling by TAPSE/sPAP predicts outcome in heart failure (HF). This study aims at investigating the thresholds for the increase in mortality risk of tricuspid annular plane systolic excursion (TAPSE), of systolic pulmonary artery pressure (sPAP) and of their ratio (TAPSE/sPAP), in HF patients with reduced (HFrEF) or preserved (HFpEF) left ventricular ejection fraction, of ischemic or nonischemic etiology, and in subjects with cardiovascular risk factors (CVRF). TAPSE and sPAP were obtained in 1,660 patients with HFrEF, 718 with HFpEF, 210 subjects with CVRF and 216 healthy controls. Cox proportional hazards regression was used to assess the association between sPAP, TAPSE and TAPSE/sPAP ratio with mortality. Mortality at follow-up increased nonlinearly with increased sPAP and decreased TAPSE or TAPSE/sPAP, with cut-off values of 33 mmHg, 19 mm and 0.68 mm/mmHg respectively. The results were essentially the same in HF of different etiologies or categories, and in subjects with CVRF except for the absence of significant impact of TAPSE alone on outcome in HFpEF. The prediction of outcome by TAPSE/sPAP was more robust than by sPAP or TAPSE alone as assessed by different metrics. The TAPSE/sPAP ratio better than TAPSE or sPAP alone predicts outcome in HF patients regardless of etiology and category and in asymptomatic subjects with CVRF. The prognostic thresholds are positioned at the upper limits of normal for sPAP and within normal limits for TAPSE/sPAP.