Right Ventricular-Pulmonary Artery Uncoupling and Strain in Acute Heart Failure

Abstract

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.

Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02638142.

Keywords: acute heart failure; longitudinal strain; prognosis; pulmonary circulation; right ventricle; ventricular–arterial coupling.

Figure 1. Study population initially enrolled and final sample size.

HF indicates heart failure; and LVEF, left ventricular ejection fraction.

Figure 2. Area under the curve for RV strain/PASP versus TAPSE/PASP for identifying patients with events in the whole population.

AUC indicates area under the curve; PASP, pulmonary artery systolic pressure; RV right ventricle; and TAPSE, tricuspid annular plane systolic excursion.

Figure 3. Cubic spline analysis and Kaplan–Meier curves to assess the relationship between the risk of event and each of the RV‐PA coupling indices modeled as continuous variable.

Upper panels: Adjusted restricted cubic spline curves for TAPSE/PASP (left) and RV strain/PASP (right). Bottom panels: Kaplan–Meier curves drawn for TAPSE/PASP ratio (left) and RV strain/PASP (right). PASP indicates pulmonary artery systolic pressure; RV, right ventricle; and TAPSE, tricuspid annular plane systolic excursion.

Figure 4. Area under the curve for RV strain/PASP versus TAPSE/PASP for identifying patients with events in acute heart failure and reduced (left panel) or preserved (right panel) ejection fraction.

AUC indicates area under the curve; LVEF, left ventricular ejection fraction PASP, pulmonary artery systolic pressure; RV, right ventricular; and TAPSE, tricuspid annular plane systolic excursion.