Acute myocardial infarction due to thrombolytic reperfusion of chronically occluded saphenous vein coronary bypass grafts

Late occlusion of saphenous vein grafts is a major cause of recurrent angina in the years after successful coronary artery bypass surgery. Reestablishment of circulation to the involved artery is problematic, because direct angioplasty may be precluded by chronic occlusion of the native artery and extensive thrombus in the occluded vein graft. It has recently been demonstrated that chronically occluded aortocoronary saphenous vein grafts can be successfully recanalized by prolonged low-dose intragraft infusions of urokinase.^1-5 Hartmann et al² achieved recanalization in 11 of 12 chronically occluded grafts using 16- to 72-hour urokinase infusions in total doses ranging from 870,000 to 6,290,000 U. Marx et al³ reported recanalization in 8 of 10 grafts with shorter urokinase infusions. Neither investigator reported significant cardiovascular complications as a result of the procedure. We report on 2 consecutive patients who developed acute myocardial infarction as a direct result of successful thrombolytic reperfusion of chronically occluded saphenous vein grafts.