Fatal quinidine-induced thrombocytopenia following open-heart surgery.

Three patients developed quinidine-induced thrombocytopenia within 3 months of our initiating quinidine therapy after open-heart surgery. One patient recovered from thrombocytopenic purpura after quinidine was discontinued. The 2 other patients presented with thrombocytopenic purpura and gingival bleeding over several days. Both patients developed headaches and succumbed to intracerebral hemorrhage in spite of the immediate cessation of quinidine therapy on admission and treatment with corticosteroids and platelet transfusions. In the light of this experience, we recommend that quinidine therapy of perioperative arrhythmias in patients undergoing open-heart surgery be re-evaluated, both at the time of discharge from the hospital and 1 month postoperatively, with an aim towards earlier discontinuation of quinidine whenever possible. Although a rare occurrence, quinidine-induced thrombocytopenia can evolve into a lethal cerebral hemorrhage. The response to current treatment of this rare complication is unpredictable.