Acute coronary occlusion occurring after successful percutaneous transluminal coronary angioplasty: temporal relationship to discontinuation of anticoagulation.

The incidence and prognosis of acute coronary reocclusion occurring after patients had left the catheterization laboratory following a successful percutaneous transluminal coronary angioplasty (PTCA) procedure and the temporal relation of this event to the discontinuation of systemic heparin administration were analyzed in a series of 1238 consecutive patients. Acute reocclusion, 1 to 96 hours after successful PTCA, occurred in 22 of 1238 patients (1.8%). Patients undergoing PTCA in the setting of acute myocardial infarction were excluded. Out of 22 patients, 15 had a nonocclusive dissection and four had evidence of small intracoronary thrombus immediately post-PTCA, with no evidence of flow disturbance. Acute reocclusion occurred within 5 hours of heparin discontinuation in 12 patients or while they were receiving inadequate anticoagulation (four patients). In 16 of 22 (73%) patients, acute reocclusion was temporally related to a time of diminished anticoagulation. Redilation was attempted in 14 patients and was ultimately successful in five patients (36%). Ten patients required coronary artery bypass surgery and three patients died. Our findings suggest that acute reocclusion after an initially successful PTCA has a poor outcome and seems to be temporally related to the loss of effective anticoagulation in most of these patients. It is advisable to discontinue heparin infusion at a time when facilities for urgent revascularization are available.