Impact of Clopidogrel Loading for Coronarography on Bleeding After Urgent First Time CABG.

Background: Excessive bleeding impairs outcome after coronary artery bypass grafting (CABG). Clopidogrel in combination with aspirin, given before percutaneous coronary intervention, have become the standard for stent thrombosis prevention. Some premedicated patients, however, are found to need surgical treatment, thus platelet inhibition caused by clopidogrel becomes a concern for post operation major bleeding.

Aims: This study was designed to evaluate the impact of preoperative clopidogrel on bleeding and outcomes after coronary artery bypass graft surgery (CABG).

Methods: The study represent a observational retrospective analysis of collected data. The follow up of 223 treated with clopidogrel and aspirin and 77 patients not receiving treatment with platelet antagonist 7 days before CABG are analyzed.

Results: The groups were comparable in age, gender, body surface area, preoperative hematocrit, preoperative prothrombin time and prior myocardial infarction. The clopidogrel group had higher12h and 24h mean chest tube output (at 12h mean 519.7ml vs 353.1 ml, p < 0.05, at 24h mean 756.6 ml vs 563.5 ml, p<0.05). Moreover, reoperation for bleeding was 4.5-fold higher in the clopidogrel group (5.9% vs. 1.3%, p <0.01), and more transfusions of red blood cells (3.23U vs 2.6 U, p<0.05), platelets (1.53U vs 1.23U, p<0.01) and fresh frozen plasma (0.84U vs 0.36 U, p<0.01). The clopidogrel group also showed a longer mechanical ventilation time (16.9h vs 12.9 h p = 0.03) and trend towards more prolonged stay in ICU (2.08 days vs 1.7 days p= 0.048).

Conclusions: Clopidogrel in combination with aspirin before CABG is associated with higher postoperative bleeding, exposure to blood products and morbidity. These findings raise concern regarding the routine administration of clopidogrel before anticipated but undecided coronary stent implantation.