Acute kidney injury after heart transplantation: A systematic review and meta-analysis

Acute kidney injury (AKI) after heart transplantation (HT) remains incompletely understood. This systematic review and meta-analysis aimed to estimate the pooled incidence of AKI and AKI requiring renal replacement therapy (RRT) after HT, assess associated mortality risks and identify characteristics associated with AKI requiring RRT.

A systematic literature search identified original studies reporting the incidence of AKI after HT using standardized definitions or reporting AKI requiring RRT. Meta-analyses were conducted using random-effects models.

Forty-eight studies covering 14,389 patients were included. The pooled incidence of AKI was 57.05% (95% CI: 49.51-64.28), and AKI requiring RRT occurred in 16.99% (95% CI: 13.58-21.04). Among patients with AKI, 30-day and one-year mortality were of 12.96% (95% CI: 9.80-16.94) and 18.51% (95% CI: 14.56-23.23) respectively. AKI was associated with an approximately threefold increase in 30-day (OR: 2.92; 95% CI: 2.02-4.22) and one-year mortality (OR: 3.07; 95% CI: 1.76-5.34). In patients requiring RRT, 30-day and one-year mortality were 26.47% (95% CI: 18.46-36.41) and 35.13% (95% CI: 28.78-42.06), respectively. AKI requiring RRT was associated with and increased 30-day mortality of more than twelvefold (OR: 12.11; 95% CI: 6.05-24.24) and one-year mortality of more than fivefold (OR: 5.40; 95% CI: 3.88-7.51) Characteristics associated with AKI requiring RRT included higher body mass index, elevated baseline creatinine, chronic kidney disease, perioperative extracorporeal membrane oxygenation support, and longer cardiopulmonary bypass time.

AKI is highly prevalent after HT and is strongly associated with increased early and late mortality, particularly in patients requiring RRT.