ANTICOAGULATION IS UNNECESSARY AFTER BIOLOGICAL AORTIC-VALVE REPLACEMENT

Background-Opinion differs as to whether anticoagulation is beneficial in preventing ischemic stroke in the early postoperative period after biological aortic valve replacement (AVR), The purpose of this study was to determine whether early anticoagulation with heparin and warfar in confers any significant advantage for patients undergoing such repl acement. Methods and Results-Patients undergoing biological AVR betwee n 1987 and 1996 were divided retrospectively into 2 groups based on th eir postoperative anticoagulation. Group A (109 patients) received hep arin followed by warfarin for 3 months (prothrombin time, 20 to 25 sec onds). Group B (76 patients) received no postoperative anticoagulation . Patients were followed for cerebral ischemic events, bleeding, repea t operation, hospital stay, and survival. There were 5 (4.6%), 3 (2.8% ), and 12 (11%) postoperative cerebral ischemic events for group A at time points of <24 hours, 24 hours to 3 months, and >3 months, respect ively; for group B patients, 3 (3.9%), 2 (2.6%), and 9 (11.8%) events were seen during the same respective time periods. There were no stati stically significant differences for ischemic events during any of the se time periods for the 2 groups. Bleeding complications occurred in 1 0 (9.2%) group A and 7 (9.2%) group B patients. Mean hospital stay was 12 days for both groups. Repeat operative AVR was required in 6 (5.5% ) group A and 7 (9.2%) group B patients. A comparison of Kaplan-Meier survival rates between groups A and B (mean follow-up, 47+/-26 and 59/-30 months, for groups A and B, respectively) was not statistically s ignificant (P=0.60). Survival rates were 93%, 84%, and 62% at 1, 5, an d 7 years for group A and 87%, 74%, and 67% for group B, respectively. Conclusions-Early anticoagulation after AVR confers no advantage in t he prevention of early cerebral ischemic events after biological AVR. No disadvantage in terms of bleeding or prolonged hospital stay was in curred by early anticoagulation, Long-term valve function and survival were not adversely affected by withholding early anticoagulation. We conclude that early anticoagulation after biological AVR is unnecessar y.