Late postoperative tamponade following coronary artery bypass grafting in patients on antiplatelet therapy.

Myocardial revascularization was performed in 1,361 patients over a 66-month period (February, 1978 to August, 1983) without a single occurrence of late cardiac tamponade. During a subsequent 4-month-period, aspirin and dipyridamole were administered routinely to all coronary bypass patients. The incidence of late cardiac tamponade rose significantly (p less than 0.001) to 3 of 85 patients (3.5%). Routine perioperative administration of aspirin and dipyridamole to patients undergoing myocardial revascularization may be associated with an increased incidence of delayed cardiac tamponade.