Elevated pulmonary arterial elastance and right ventricular uncoupling are associated with greater mortality in advanced heart failure.

BACKGROUND

The objectives of this study were to describe right ventricular-pulmonary arterial elastance coupling hemodynamic phenotypes and their frequency in patients with advanced heart failure and to evaluate the association of elastance-based indices with all-cause mortality, cardiac transplantation, and left ventricular assist device therapy.

METHODS

This study included 175 patients with heart failure undergoing right heart catheterization to evaluate candidacy for advanced therapies and 21 healthy controls. We modified a single-beat approach to elastance to account for the magnitude of pulmonary arterial pressure and estimated right ventricular end-systolic elastance (Ees), pulmonary arterial elastance (Ea), and the Ees:Ea ratio. We defined elevated pulmonary arterial load as an Ea > 0.5 mm Hg/ml, and ventriculo-arterial uncoupling as an Ees:Ea < 0.8. We evaluated associations between Ees, Ea, and Ees:Ea with all-cause mortality and composite event-free survival using multivariable Cox proportional-hazard models, adjusted for age and sex.

RESULTS

All 21 controls had Ea ≤ 0.5 mm Hg/ml and Ees:Ea ≥ 0.8. Of 175 patients with heart failure, 63% had Ea > 0.5 mm Hg/ml. Ees:Ea was lower in patients than in controls (p < 0.001), and 47% of the patients demonstrated Ees:Ea < 0.8, including 8% with normal Ea. In median follow-up of 2.2 (0.8-4.6) years, 53 died, 37 received cardiac transplantation, and 33 received a left ventricular assist device. By multivariable analysis, Ea (hazard ratios [HR]: 2.01, 95% CI 1.18-3.41) and Ees:Ea (HR: 0.46, 95% CI: 0.26-0.82) were independently associated with mortality, whereas Ees was not.

CONCLUSIONS

Right ventricular-pulmonary vascular coupling is frequently impaired in heart failure and associated with greater mortality. Elevated pulmonary arterial elastance is associated with greater mortality even when coupling is preserved.