"Bridging therapy" with low molecular weight heparin in patients with coronary stents undergoing surgery

Abstract

Background: Bridging discontinuation of antithrombotic agents with low molecular weight heparin (LMWH) in patients with coronary stents undergoing cardiac or non cardiac surgery is not infrequent in clinical practice. However, safety and efficacy data on this approach are sparse. Methods: Patients with coronary stent(s) undergoing surgery between March 2003 and February 2012 were included. The primary efficacy endpoint was the 30-day incidence of major adverse cardiac or cerebrovascular events (MACCE), defined as the composite of cardiac death, myocardial infarction, stroke, acute coronary syndrome leading to hospitalization, congestive heart failure leading to hospitalization and definite or probable stent thrombosis. The primary safety endpoint was the 30-day incidence of Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding. Results: Of 748 patients analyzed, 251 (33.6%) were on dual antiplatelet therapy (DAPT) at the time of surgery. Among them, LMWH bridging was used in 144 (57%). At 30 days, the risk of MACCE was not significantly decreased by LMWH bridging (13% vs 8%, odds ratio [OR] 1.8, 95% confidence interval [95% CI] 0.7-4.2; P=0.20). This finding was consistent after adjusting for age, insulin dependent diabetes mellitus, chronic kidney disease, prior drug eluting stent (DES) implantation, surgical risk and American Society of Anesthesiologists (ASA) score. On the other side, patients on LMWH bridging experienced a significantly higher risk of 30-day TIMI major or minor bleeding (33% vs 11%, OR 4.0, 95% CI 2.0-7.9, P<0.001). After adjustment for age, body mass index, female gender, renal failure, insulin dependent diabetes mellitus, prior stroke, prior ulcer, prior DES implantation, use of vitamin K antagonists, surgical risk, ASA score, and dual antiplatelet therapy discontinuation at surgery, LMWH bridging remained independently associated with 30-day TIMI major or minor bleeding (adjusted OR 2.3, 95% CI 1.0-5.0; P=0.04). Conclusions: LMWH bridging in patients with coronary stents undergoing surgery is a detrimental practice, resulting in no advantage on cardiac outcomes at 30 days, and a significant risk of bleeding.