Risk of ischemic stroke in Cuban children with sickle cell anemia: Study with transcranial Doppler

INTRODUCTION: Elevated flow velocity in the internal carotid artery or middle cerebral artery, detected by transcranial Doppler (TCD) ultrasonography, predicts an increased risk of stroke in children with sickle cell disease. OBJECTIVE: To describe the characteristics of TCD and to evaluate ischemic stroke risk in children with sickle cell anemia. METHODS: We prospectively studied 107 patients less than 16 years old remitted from Hematology and Immunology Institute of Havana with the diagnosis of sickle cell disease. The risk of stroke was classified according to the highest time averaged mean blood flow velocity (TAMM), according to STOP study. RESULTS: The mean age of patients was 9.6 years. An 86.9% have TAMM velocity in middle cerebral arteries below to 170 cm/s and 7% over 200 cm/s. There was an inverse correlation between the age and the level of the hemoglobin with the blood flow velocity in the studied arteries. We found inter-hemispheric asymmetry in the flow velocity of anterior cerebral artery in 38.3% of the cases, followed by the middle cerebral artery (30.8%) and the 15.9% of the extracraneal internal carotid artery. CONCLUSION: The risk of ischemic stroke in these patients appears to be lower than that described in the literature. The high flow velocity in cerebral arteries is uncommon. In contrast, hemispheric asymmetries between homologous vessels are frequent.