Risk factors for PO-AKI include age >50 years, male sex, glomerular filtration rate <60 ml/min/1.73 m2, diabetes mellitus, heart failure, ascites, hypertension, emergency surgery, intraperitoneal surgery, number of medications, use of angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), high American Society of Anesthesiology Physical Status classification score and albuminuria. The gene discussed is ACE; the disease is heart failure.