Response To Letter Regarding Article, "Platelet Function Measurement-Based Strategy To Reduce Bleeding And Waiting Time In Clopidogrel-Treated Patients Undergoing Coronary Artery Bypass Graft Surgery: The Timing Based On Platelet Function Strategy To Reduce Clopidogrel-Associated Bleeding Related To Cabg (Target-Cabg) Study"

Background-Aspirin and clopidogrel therapy is associated with a variable bleeding risk in patients undergoing coronary artery bypass graft surgery (CABG). We evaluated the role of platelet function testing in clopidogrel-treated patients undergoing CABG. Methods and Results-One hundred eighty patients on background aspirin with/without clopidogrel therapy undergoing elective first time isolated on-pump CABG were enrolled in a prospective single-center, nonrandomized, unblinded investigation (Timing Based on Platelet Function Strategy to Reduce Clopidogrel-Associated Bleeding Related to CABG [TARGET-CABG] study) between September 2008 and January 2011. Clopidogrel responsiveness (ADP-induced platelet-fibrin clot strength [MAADP]) was determined by thrombelastography; CABG was done within 1 day, 3-5 days, and > 5 days in patients with an MA(ADP) > 50 mm, 35-50 mm, and < 35 mm, respectively. The primary end point was 24-hour chest tube drainage and key secondary end point was total number of transfused red blood cells. Equivalence was defined as <= 25% difference between groups. ANCOVA was used to adjust for confounders. Mean 24-hour chest tube drainage in clopidogrel-treated patients was 93% (95% confidence interval, 81-107%) of the amount observed in clopidogrel-naive patients, and the total amount of red blood cells transfused did not differ between groups (1.80 U versus 2.08 U, respectively, P=0.540). The total waiting period in clopidogrel-treated patients was 233 days (mean, 2.7 days per patient). Conclusions-A strategy based on preoperative platelet function testing to determine the timing of CABG in clopidogrel-treated patients was associated with the same amount of bleeding observed in clopidogrel-naive patients and approximate to 50% shorter waiting time than recommended in the current guidelines. Clinical Trial Registration-URL: http://www.clinicaltrials.gov.Unique identifier: NCT00857155. (Circ Cardiovasc Interv. 2012;5:261-269.)