Right ventricular-pulmonary artery uncoupling and strain in acute heart failure

Background: Assessment of right ventricular-pulmonary artery coupling plays a crucial role in risk stratification, monitoring efficacy, and predicting outcomes in chronic heart failure patients. However, data in acute heart failure (AHF) are still lacking. Methods and results: This multicenter observational study includes 425 patients with AHF: 248 with reduced left ventricular ejection fraction (<50%) and 177 with preserved left ventricular ejection fraction (≥50%). Pulmonary artery systolic pressure (PASP), tricuspid annular plane systolic excursion (TAPSE), longitudinal 2-dimensional strain of right ventricular (RV) free wall, and the RV end-diastolic diameter were measured by echocardiography. TAPSE/PASP and longitudinal 2-dimensional strain of RV free wall/PASP ratios were calculated as noninvasive surrogates of right ventricular-pulmonary artery coupling. The end point was a composite of all-cause death/HF-related hospitalizations assessed at 180 days. At 180 days, 197 patients (46.4%) reached the end point. After multivariable adjustment for RV end-diastolic diameter, E/e' ratio, left ventricular ejection fraction, and natriuretic peptides, although both TAPSE/PASP (hazard ratio [HR], 0.49 [95% CI, 0.25-0.27]; P=0.042) and longitudinal 2-dimensional strain of RV free wall/PASP (HR, 0.30 [95% CI, 0.13-0.67]; P=0.004) had a statistically significant association with the end point, and longitudinal 2-dimensional strain of RV free wall/PASP better discriminated between patients with and without events compared with TAPSE/PASP (area under the curve, 0.70 versus 0.66; P=0.0041). Interestingly, the superiority of longitudinal 2-dimensional strain of RV free wall/PASP over the TAPSE/PASP ratio was more evident in patients with AHF with preserved ejection fraction (area under the curve, 0.72 versus 0.64; P<0.001) than in those with AHF with reduced ejection fraction (AUC, 0.67 versus 0.64; P=NS). Conclusions: In patients with AHF, both TAPSE/PASP and longitudinal 2-dimensional strain of RV free wall/PASP are independent predictor of prognosis. However, longitudinal 2-dimensional strain of RV free wall/PASP showed a superior discriminator capability in identifying patients with events, mainly in the AHF with preserved ejection fraction subgroup.