Comparison of Functional Outcome and Stroke Recurrence in Patients with Embolic Stroke of Undetermined Source (ESUS) vs. Cardioembolic Stroke Patients

BACKGROUND Embolic stroke of undetermined source (ESUS) recurrence and functional outcome from long-term follow-up is not well delineated. The purpose of this study is to compare these functional variables between ESUS vs. cardioembolic stroke (CS) patients. METHODS We analyzed data of consecutive ESUS and CS patients from our institutional database, from January 2003 until April 2015. The endpoints were stroke recurrence, mortality and poor clinical outcome (Modified Rankin Score 3-6), at discharge, 6 months and final follow-up. Adjusted multivariate Cox analysis and Kaplan-Meier curves were used to estimate the probability of recurrence and death. RESULTS 149 ESUS (median age 44 years) and 235 CS (median age 66 years) consecutive patients were included in the study. Median follow-up period for the entire sample was 19 months (interquartile range 6.0-45.0 months). Stroke recurrence was similar between ESUS and CS patients (5.4% vs. 9.8% respectively, p = 0.12). Death occurred in 30 CS cases (12.8%), with a cumulative probability of survival of 77%. Poor functional outcome was present in 58.3%, 54.0% and 54.9% at discharge, 6 months and final follow-up respectively in CS patients, significantly worst compared to ESUS cases (HR 3.1; CI 95% 1.96-4.68). Oral anticoagulation presents with a HR 8.01 for recurrence, and antiplatelet therapy had the highest risk for recurrence for both groups (HR 24.3). CONCLUSION ESUS patients are substantially younger than CS patients but have a stroke recurrence rate similar to CS patients, with a lower mortality rate, and better functional outcome on long-term follow-up.