Right ventricular recovery after bilateral lung transplantation for pulmonary arterial hypertension†.

OBJECTIVES

Pulmonary arterial hypertension (PAH) is a progressive and often fatal disease characterized by increased pulmonary vascular resistance (PVR) and right ventricular (RV) failure. End-stage PAH is often an indication for a lung transplant (LTX). Our goal was to study ventricular recovery using cardiac magnetic resonance imaging late after LTX.

METHODS

We studied 10 patients with PAH who underwent isolated bilateral LTX. RV and left ventricular (LV) volumes, function and mass were measured. In addition, the RV stroke volume/end-systolic ratio (SV/ESV), the LV eccentricity index, the RV/LV volume ratio, the area of the tricuspid valve annulus and the severity of tricuspid regurgitation (TR) were calculated.

RESULTS

The median age was 44 [30-54] years and the mean PVR was 1020 ± 435 dynes·s·cm - 5 . Six patients had ≥ moderate TR. After LTX, the RV ejection fraction increased from 32 to 64% ( P  < 0.001) and both RV volume (from 118 to 51 ml/m 2 , P  < 0.001) and RV mass (from 69 to 33 g/m 2 , P  < 0.001) decreased. The mean SV/ESV ratio increased from 0.5 to 1.9 ( P  < 0.001) and the LV mass increased from 55 to 61 g/m 2 ( P  = 0.005). There was a decrease in both the LV eccentricity index (from 2.8 to 1.1, P  < 0.001) and the RV/LV volume ratio (from 2.3 to 0.8, P  < 0.001). The area of the tricuspid valve annulus also decreased (from 9.8 to 4.6 cm 2 /m 2 , P  < 0.001); no patient had ≥ mild TR post-LTX.

CONCLUSIONS

Cardiac magnetic resonance imaging confirms ventricular recovery after isolated bilateral LTX for end-stage PAH.