A Prognostic Score To Predict Atrial fibrillation Recurrence After External Electrical Cardioversion—SLAC Score

INTRODUCTION: Atrial fibrillation (AF) recurrence after a successful external electrical cardioversion (ECV) is common. Assessing an individual's risk of AF recurrence is a critical part of the treatment plan. We aimed to develop a prognostic prediction score to predict AF recurrence in AF patients who underwent successful ECV. METHODS: A retrospective cohort study that included AF patients who underwent successful ECV was conducted with a primary outcome of AF recurrence at 6 months. Logistic regression analysis was done to identify variables, and a prognostic prediction score was created and internally validated. RESULTS: Four prognostic predictors were identified, including the type of AF, persistent AF (1 point) and long-standing persistent AF (4 points), previous cardioversion (1 point), stroke/transient ischemic attack (3 points), and left atrial volume index ≥40 mL/m 2 (6 points). The total score of 14 was further divided into 3 risk groups; low-risk (0-2 points), moderate-risk (3-7 points), and high-risk (8-14 points). The positive likelihood ratio for a moderate-risk patient was 2.08 (95% CI, 1.64-2.63) and for a high-risk patient was 7.90 (95% CI, 2.48-25.17). The score showed good discrimination power with the c-statistic of 0.74 (95% CI, 0.69-0.79). CONCLUSIONS: A simple prognostic prediction score for AF recurrence after successful ECV was created with a promising internally validated discrimination power. An external assessment of its usefulness as a tool to identify patients with low, moderate, and high risk for AF recurrence is warranted.