Abstract TP230: Ischemic Strokes in Anti-Coagulated Patients - Treatment Failure or Alternate Etiology?

Abstract

Background: Patients experiencing ischemic strokes while already on therapeutic anti-coagulation are often considered anti-coagulant failures if they are compliant with treatment, and pose a management challenge. Stroke etiology in such patients is also often overlooked and they are routinely switched to alternate anticoagulant or combined with an anti-platelet therapy, although evidence is lacking if doing so prevents future ischemic strokes. Objective: To identify determinants and mechanisms of strokes in patients who experience ‘breakthrough ischemic strokes’ while already on therapeutic anticoagulation. Methods: We conducted a retrospective case-cohort study of patients presenting to Cleveland Clinic Akron General between January 2013 - December 2017. Patients were included if they had an ischemic stroke diagnosis on admission and were already on therapeutic anticoagulation at the time, who were then compared against a matched cohort from the same time period. Treatment compliance was determined using manual chart review. Stroke etiology was determined and dichotomized into embolic stroke (ES) vs Non-embolic stroke (NES) etiology based on their history, imaging and ancillary findings. Results: We identified 64 patients who were true breakthrough strokes with complete data and compared them to 119 matched controls. Both groups were similar in age (72±13 years among cases vs 72±16 among cohorts, p=0.795) and sex (Females 69 (58%) among cases vs 30 (47%) among cohorts, p=0.150). History of auto-immune disease was the only co-morbid condition not dependent on anticoagulation status which was significantly higher among cases (9(14%) vs 4(3%), p=0.013). Stroke etiology was similar among both groups, with the anti-coagulated group not necessarily showing a trend towards higher incidence of ES (49 (77%) in cases vs. 83 (70%) in cohort, p=0.327). Conclusion: Ischemic strokes among patients on therapeutic anticoagulation do not necessarily differ in stroke mechanisms compared to routine ischemic strokes, and require a thorough, individualized approach to prevent future stroke risks.