Isolated Broca's area aphasia and ischemic stroke mechanism.

Cerebral embolism has been considered to be the most common stroke mechanism when the resulting stroke has at least some amount of aphasia as part of its clinical manifestations. To determine stroke mechanism and risk factor profile in patients with isolated Broca's area aphasia (Broca's infarct), we studied 34 consecutive patients with recent infarcts whose only or predominant clinical feature was that of nonfluent speech and compared these cases with 68 control patients with cortical infarcts in the middle cerebral artery distribution whose clinical features were not restricted to an isolated aphasia. Controls were age- and sex-matched and were selected from ischemic infarcts seen at our institutions over the same observation period. Broca's infarct patients had significantly more cardiac-source emboli, more cardiac thrombi identified on echocardiography, and less large-artery atherosclerosis (each P = .02). These differences in stroke mechanism may suggest different diagnostic and therapeutic decision making for those ischemic stroke patients presenting with isolated Broca's aphasia.