Abstract
Introduction: Embolic strokes of an undetermined source may be caused by various potential embolic sources, which can be better managed by anticoagulant or antiplatelet therapy. Identifying these sources may have diagnostic and therapeutic implications. Our objectives were to assess the prevalence and overlap of different potential embolic sources identified in a population of patients with embolic strokes of undetermined sources, and to evaluate the stroke recurrence rate according to the type and number of potential embolic sources.
Methods: We used data from consecutive patients with ischemic stroke admitted to the department of neurology in Fattouma Bourguiba hospital (Monastir, Tunisia), between January 2017 and December 2020. Patients who met the embolic strokes of undetermined source diagnostic criteria according to the criteria of the Cryptogenic Stroke “embolic strokes of undetermined source” International Working Group were selected. The presence of each potential embolic source was assessed, and patients were categorised according to the identified potential embolic sources. The main outcome was ischemic stroke recurrence, and it was collected prospectively during follow-up after the index stroke.
Results: Among 330 patients admitted between 2017 and 2020, 66 (20.6%) were classified as embolic strokes of undetermined source (68.2% were men, mean age 57 ±11 years). The three most prevalent potential embolic sources were atrial cardiopathy (N = 47/66; 71.2%), arterial atherosclerosis (N = 46/66; 69.7%) and left ventricular disease (N = 26/66; 39.4%). Most patients (N = 56/66; 84.8%) had ≥2 potential embolic sources. After 6-month of follow up, ischemic stroke recurrence occurred in 18 (27.3%) patients. In survival analysis, the type and the number of potential embolic sources were not statistically associated with stroke recurrence.
Conclusion: Most patients with embolic strokes of undetermined source had multiple potential embolic sources, which overlap considerably. The type and number of potential sources were not associated with stroke recurrence. This finding may explain the negative results of large trials of secondary prevention in the Embolic strokes of undetermined source population.