Abstract 4305: Peri-operative Anti-thrombotic Therapy and Clinical Outcomes in Patients With Prior Coronary Stenting Undergoing Non-Cardiac Surgery
Background: Non-cardiac surgery performed following coronary stent implantation is associated with an increased risk of cardiovascular events. This risk is greatest for up to 8 weeks following stent implantation. The influence of anti-thrombotic therapy on outcomes in patients undergoing surgery beyond 8 weeks remains to be determined.
Methods: We examined clinical outcomes for 128 patients who underwent non-cardiac surgery at least 8 weeks following coronary stent implantation in Edinburgh between November 2003 and December 2008. The primary endpoint was death, acute coronary syndrome (ACS) or stroke occurring within 30 days of surgery.
Results: Patients were predominantly male (73%) with a mean age of 66 years. Twenty-three (18%) received at least 1 drug-eluting stent. The median duration from stent implantation to surgery was 15 months (range 2–51). The primary endpoint occurred in 9 patients (8 ACS and 1 stroke). Patients who suffered a cardiovascular event were older (74±9 vs 65±10 years, p=0.02) but had similar comorbidities and index coronary revascularization profiles compared to those who did not. Thirty-eight (30%) patients received no oral anti-platelet agent peri-operatively, 78 (61%) received 1, and 12 (9%) received 2 agents. Patients receiving no anti-platelet therapy peri-operatively had more cardiovascular events compared to patients treated with at least 1 anti-platelet agent (16% vs 3%, p=0.02). Pre-operative discontinuation of aspirin was associated with more cardiovascular events compared to maintenance of therapy (16% vs 4%, p=0.04). There were no differences in peri-operative anti-platelet therapy or outcomes according to stent type (bare metal vs drug-eluting) and no association between anti-platelet therapy and bleeding. Patients treated with low-molecular-weight heparin peri-operatively had more major bleeding (18% vs 6%, p=0.04).
Conclusions: Patients undergoing non-cardiac surgery at least 8 weeks following coronary stent implantation should be maintained on at least 1 anti-platelet agent peri-operatively. Pre-operative discontinuation of aspirin should be avoided. Low-molecular-weight heparin use appears to increase major peri-operative bleeding without preventing cardiovascular events.