Carotid artery and heart disease in subtypes of cerebral infarction.

BACKGROUND AND PURPOSE: The aim of the study was to determine the prevalences of carotid artery disease and major and minor potential cardioembolic sources (1) in patients with cerebral infarction and age-matched control subjects and (2) in different clinical subtypes of cerebral infarction. METHODS: A series of 166 consecutive patients with cerebral infarction and 59 control subjects was examined. The study protocol included clinical subtyping of the cerebral infarctions, ultrasonography of the carotid arteries, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), ECG, and examination of the brain with computed tomography, magnetic resonance imaging, or autopsy. RESULTS: Carotid artery stenosis > or = 80% or occlusion was present in 35 (21%) patients but in no control subjects (P or = 80% or occlusion, atrial fibrillation, or a major cardioembolic source detected at TTE or TEE was more frequent among patients with cortical symptoms from anterior or middle cerebral artery territories than among those with lacunar syndromes (66% versus 22%, respectively). The probable source of cerebral infarction was identified in most of the 166 patients: cardiac embolism in 28% of cases (n = 46), carotid artery disease in 8% (n = 14), both cardiac embolism and carotid artery disease in 7% (n = 11), and lacunar infarction in 23% (n = 38). In 57 (34%) of the patients no unequivocal cause of the cerebral infarction was found. CONCLUSIONS: The prevalences of carotid artery and heart disease differ significantly between clinical subtypes of cerebral infarction. The cause of cerebral infarction remains uncertain in one third of patients. Because a minor potential cardioembolic source occurs in about 50% of both patients and control subjects, this finding is of questionable value as a risk factor for stroke in the elderly.