Objectives: Raised pulmonary artery pressure (PAP), trans-pulmonary gradient (TPG) and pulmonary vascular resistance (PVR) are risk factors for poor outcomes after heart transplant in patients with secondary pulmonary hypertension (PH) and may contraindicate transplant. Unloading of the left ventricle with an implantable left ventricular assist device (LVAD) may reverse these pulmonary vascular changes. We studied the effect of implanting centrifugal LVADs in a cohort of patients with secondary PH as a bridge to candidacy.
Methods: Pulmonary haemodynamics on patients implanted with centrifugal LVADs at a single unit between May 2005 and December 2010 were retrospectively reviewed.
Results: Twenty-nine patients were implanted with centrifugal LVADs (eight HeartWare ventricular assist device (HVAD), HeartWare International, USA and 21 VentrAssist, Ventracor Ltd., Australia). Seventeen were ineligible for transplant by virtue of high TPG/PVR. All the patients were optimized with inotrope/balloon pump followed by LVAD insertion. Four required temporary right VAD support. Thirty-day mortality post-LVAD was 3.4% (1 of 29) with a 1-year survival of 85.7% (24 of 28). Thirteen patients have been transplanted to date: 30-day mortality was 7.7% (1 of 13) and 1-year survival was 91% (10 of 11). Baseline and post-VAD pulmonary haemodynamics were significantly improved: systolic PAP (mmHg), mean PAP, TPG (mmHg) of 57 ± 9.5, 42 ± 4.4 and 14 ± 3.9 reduced to 32 ± 7.5, 18 ± 5.5 and 9 ± 3.3, respectively. PVR reduced from 5 ± 1.5 to 2.1 ± 0.5 Wood units (P < 0.05).
Conclusions: In selected heart failure patients with secondary PH, use of centrifugal LVAD results in significant reductions in PAP, TPG and PVR, which are observed within 1 month, reaching a nadir by 3 months. Such patients bridged to candidacy have post-transplant survival comparable with those having a heart transplant as primary treatment.
Keywords: Bridge to candidacy; Centrifugal; Heart transplant; Pulmonary hypertension; Ventricular assist device.