Renal Outcomes After Lung or Combined Heart-Lung Transplantation in Pulmonary Hypertension

Renal impairment is considered a contra-indication for lung (LTX) or combined heart-lung (HLTX) transplantation due to increased mortality. We hypothesized that renal impairment in pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) is the result of reduced cardiac output and should be partly reversible after LTX. We performed a retrospective analysis in 67 consecutive PAH and CTEPH patients who underwent (H)LTX, to investigate the postoperative evolution of renal function in function of baseline renal function using a mixed model effect test. Furthermore, we assessed potential predictors for postoperative renal dysfunction, renal replacement therapy (RRT) and mortality by multivariate analyses. Median baseline eGFR was 74 mL/min/1.73m². Fourteen patients were classified as KDIGO 3 preoperatively, 38 patients as KDIGO 2. Renal function significantly declined after 1 and 2 years in all patients. In patients with impaired renal function (KDIGO 2 and 3), we observed a significant improvement in eGFR 1 month after (H)LTX (p = 0.02 and p = 0.04, respectively). Baseline renal impairment ≤ 60 mL/min/1.73m² was associated with early RRT but not with further renal function deterioration, long-term RRT, or mortality. Age was a predictor of renal function decline and mortality. We conclude that renal function evolution can be biphasic after (H)LTX in PAH and CTEPH patients with baseline renal impairment, with initial improvement due to resolution of cardio-renal syndrome. Mild to moderate renal impairment was not significantly associated with renal deterioration or increased mortality.