PRISMA Flow Diagram

This study is a systematic review and meta-analysis evaluating the safety and efficacy of bivalirudin as an anticoagulant in patients with heparin-induced thrombocytopenia (HIT) undergoing cardiac surgery with cardiopulmonary bypass (CPB). Since unfractionated heparin is contraindicated in HIT, bivalirudin has emerged as the main alternative, but high-quality data remain scarce.Methods: The review followed PRISMA 2020 guidelines and was prospectively registered in PROSPERO. Searches across PubMed, Embase, and Cochrane CENTRAL identified three cohort studies (170 patients) plus 16 case reports/series. Primary outcomes were major bleeding, thromboembolic events, and mortality; secondary outcomes included transfusion needs, reoperation, circuit changes, and ICU/hospital stay.Results:Major bleeding: 10.6% pooled incidence (95% CI 6.4–16.9%).Thromboembolic events: 2.1% pooled incidence (95% CI 0.4–4.8%), with no CPB circuit thrombosis or oxygenator exchanges.Mortality: Early mortality ≤3%.Around 14% of patients required intraoperative dose adjustments, but ACT-guided protocols (480–520 s) ensured safe management.Case-based evidence confirmed feasibility in high-risk settings (pediatrics, reoperations, transplantation, renal impairment).Conclusions: Bivalirudin is a safe and effective alternative to heparin in HIT-positive patients requiring CPB, with low thrombotic risk and acceptable bleeding rates under strict ACT monitoring. Findings are consistent with international guidelines (ASH 2018, ACCP 2022), though large randomized trials are still needed to refine dosing strategies and long-term outcomes