ACE and acute kidney injury: ACEIs: angiotensin-converting enzyme inhibitors; AKI: acute kidney injury; ARBs: angiotensin receptor blockers; ARF: acute renal failure; CA: coronary angiography; CHF: congestive heart failure; Cr: creatinine; ESRD: end-stage renal disease; NAC: N-acetyl cysteine; NR: not recorded; NSTE-ACS: non–ST-segment elevation acute coronary syndrome; RCT: a randomized controlled trial; STE: ST-segment elevation.