Published September 1, 2017 | Kidney International

Pediatric heart surgeons know that the complex surgeries required to repair congenital heart defects often can result in acute kidney injury (AKI) during the days following a procedure. Now a research team from Cincinnati Children’s and the University of Aarhus in Denmark reports that some children also face a long-term risk of chronic kidney disease (CKD).

“Cardiac surgery associated-acute kidney injury (CS-AKI) in patients with congenital heart disease (CHD) is common and is associated with an increased risk for CKD,” the study states. “This association remained heightened even when applying a strict definition of CKD and adjusting for age at surgery and surgical complexity.”

CS-AKI occurs in 30 to 50 percent of patients receiving heart defect repairs. However, even when kidney function returns to near-normal, the cumulative incidence of CKD for patients with CS-AKI was 12 percent, compared to three percent among those without CS-AKI.

“We cannot conclude that cardiac surgery increases the risk of CKD. We could not assess that directly. What we did show was in this population, surgery-associated AKI increased the risk,” says co-author Stuart Goldstein, MD.

The analysis was the largest of its kind, involving data on 382 CHD patients gathered from detailed population-based registries from Denmark. The team sorted patients according to stages of AKI, then used serum creatinine values to calculate hazard ratios.

CKD poses well-established risks for people growing up with CHD, including multivessel calcification, hypertension, ventricular hypertrophy, and myocardial infarction.

“Given its frequency, AKI has the potential to feel like an unavoidable result of cardiac surgery in the CHD population,” says co-author Nicolas Madsen, MD, MPH. “However, as the field transitions from a focus on mortality alone to one of morbidity and long-term outcomes, AKI and CKD deserve particular attention.”