Summary:
Copenhagen, Denmark - Drs Moller and Steinbruchel of the Department of Cardiothoracic Surgery, Rigshospitalet, University of Copenhagen, Denmark have investigated an important topic in cardiac surgery, namely, platelet function after off-pump coronary artery bypass (OPCAB).
This topic has been looked at previously and suggested by emperical observation by surgeons in the operating room. The original article was published by Giuseppe D'Ancona and colleagues in the Heart Surgery Forum. Dr. D'Ancona surveyed surgeons in the United States performing on-pump and OPCAB surgery to see what heparinization protocols are used and whether surgeons believed that the OPCAB procedure was associated with "prothrombotic complications" in the postoperative period.
The current study authors state that "haemostasis might be better preserved compared with on-pump coronary artery bypass grafting (CABG)." Their aim was to investigate whether "better preserved haemostasis" results in a "procoagulant activity of the platelets."
Thirty patients were studied prospectively, 15 undergoing on-pump CABG and 15 undergoing OPCAB. Platelet function was evaluated four times within the first 24 h: preoperatively, postoperatively, 4 h and 1 day after surgery with a bedside whole blood clotting test.
The authors found a significant increase of platelet-activating-factor-induced platelet aggregation after OPCAB. Platelet aggregation immediately after on-pump CABG was reduced to near half of preoperative values, but within 1 day postoperatively normal platelet aggregation was regained in half of the patients.
The study authors concluded that "platelets after OPCAB were more easily activated in the early postoperative period." The effect of this on procoagulant related clinical complications were not determined in this study and this effect remains unknown.
However, the authors found that "after CABG with cardiopulmonary bypass, a temporary platelet dysfunction was found which [resolved] within the first postoperative day.
Editor's Note:
This study is important as it answers some of the empiric observations made by surgeons that the OPCAB procedure is associated with a procoagulant state. More studies are needed to study this in a prospective fashion.
