INTRODUCTION: Data on outcomes between unfractionated heparin and bivalirudin anticoagulation during percutaneous coronary intervention (PCI) in acute coronary syndromes remain inconclusive. We aimed to systematically analyze PCI outcomes by comparing unfractionated heparin and bivalirudin.

METHODS: We systematically searched Ovid MEDLINE, Ovid Embase, Ovid Cochrane Database of Systematic Reviews, Scopus, and Web of Science from database inception in 1966 through January 2024 for studies evaluating PCI outcomes comparing unfractionated heparin and bivalirudin. Two investigators independently reviewed the data. Conflicts were resolved through consensus. Random-effects meta-analyses were used.

RESULTS: A total of 10 prospective trials were identified that enrolled 42,253 individuals who presented with an acute coronary syndrome. Our analysis found that heparin when compared to bivalirudin was associated with an increased risk of trial-based definition of major bleeding [relative risk (RR): 1.68, 95% confidence interval (CI): 1.29-2.20], nonaccess site complications (RR: 4.6, 95% CI: 1.75-12.09), thrombolysis in myocardial infarction major bleeding (RR: 1.70, 95% CI: 1.20-2.41), major bleeding risks (RR: 1.87, 95% CI: 1.49-2.36), cardiovascular disease death (RR: 1.26, 95% CI: 1.02-1.57), and thrombocytopenia (RR: 1.67, 95% CI: 1.07-2.62). There were no statistically significant differences between heparin and bivalirudin for all-cause mortality, major adverse cardiovascular event, stroke, reinfarction, target vessel revascularization, and acute or stent thrombosis.

CONCLUSIONS: The present meta-analysis demonstrates bivalirudin reduces major bleeding when used for anticoagulation during PCI in patients with acute coronary syndromes and is not associated with an increased risk of stent thrombosis or major adverse cardiovascular event.