Etiological Classification of Stroke in Patients with Chagas Disease Using TOAST, Causative Classification System TOAST, and ASCOD Phenotyping

Background: Cardioembolism is considered a major pathophysiological mechanism in patients with ischemic stroke (IS) and Chagas disease (CD). However, a previous study reported that other stroke subtypes are present in more than 40% of CD patients according to the TOAST classification. Therefore, the aim of our study was to evaluate the etiologic classification of stroke in patients with CD using the Causative Classification System (CCS), the ASCOD, and the TOAST classifications in a prospective cohort of patients. Methods: Patients evaluated in our outpatient clinic from 2012 to 2015 with IS and CD were included and underwent full investigation for stroke etiology. TOAST, CCS TOAST, and the ASCOD classifications were compared. Findings: We Included 32 patients (18 men; mean age 62.7 +/-10.1 years). A total of 93.8% had at least 1 vascular risk factor; the most frequent was hypertension (87.5%). According to TOAST, we defined 87.5% as having cardioembolic stroke, being 9.4% as large-artery atherosclerotic (LAA) and 3.1% as undetermined cause. Using the CCS TOAST, 62.5% were classified as cardioaortic embolism evident and 15.6% as possible, 6.3% as small artery occlusion evident and 3.1% as probable, and 12.5% as LAA evident. When ASCOD phenotyping was applied, atherosclerosis was present in 50.1% of patients (A1 = 6.3%, A3 = 43.8%), cardiac pathology in 84.4% (C1 = 62.5%, C2 = 15.6%, C3 = 6.3%), and small-vessel disease in 66% (S1 = 9.4%, S2 = 3.1%, S3 = 3.1%). Findings: In conclusion, the use of the CCS and the ASCOD phenotyping in patients with CD confirmed a high frequency of cardioembolic IS but also showed that other etiologies are prevalent, such as large-artery atherosclerosis and small-vessel occlusion.