Thromboembolic complications in beta thalassemia major.

Thromboembolic complications in beta-thalassemia major have seldom been reported and their association with risk factors such as left ventricular failure and postsplenectomy thrombocytosis has remained speculative. In this report we describe 4 patients with unusual thromboembolic manifestations: recurrent arterial occlusion, recurrent pulmonary thromboembolism, venous thrombosis and a fatal cerebrovascular event. Although in all patients both risk factors were present, the precise causes for their thromboembolic complications were not identified. In 1 patient, however, a marked increase in hematocrit following blood transfusion resulted, in all likelihood, in a fatal cerebrovascular infarction. We suspect that these patients (constituting 4% of our beta-thalassemic group) represent a subset of those with high susceptibility to both arterial and venous thromboembolic complications.