We searched PubMed, Embase, Cochrane Library, Chinese Biomedical Literature, China National Knowledge Infrastructure, VIP Information/Chinese Scientific Journals, and WANFANG databases for randomized controlled trials (RCTs) comparing the preventive effects of PGE1 versus controls (conventional hydration, no PGE1, or placebo) on CIN in patients undergoing percutaneous coronary procedures from January 1999 to June 2016.