Secondary Precipitants of Atrial Fibrillation and Anticoagulation Therapy

Background Atrial fibrillation (AF) commonly occurs in the setting of acute conditions. We aimed to identify the acute conditions associated with secondary AF (AF precipitants) including pneumonia/sepsis, pneumothorax, respiratory failure, myocarditis, pericarditis, alcohol intoxication, thyrotoxicosis, cardiothoracic surgery, other surgery in patients with newly diagnosed AF and determine their association with subsequent oral anticoagulant use. Methods and Results We assembled a cohort of patients in the UMass Memorial Healthcare system with a new diagnosis of AF with and without AF precipitants. We used combinations of International Classification of Diseases, Tenth Revision (ICD-10) codes, Current Procedural Terminology codes, laboratory values, imaging reports, and physician notes including discharge summary texts to identify AF precipitants. We then manually reviewed the individual charts to validate presence of AF precipitants. The study sample consisted of 185 patients with and 172 patients without AF precipitants. Pneumonia/sepsis, myocardial infarction, respiratory failure, and cardiothoracic surgery were the most common precipitants identified. In multivariable analyses adjusting for age, sex, patient comorbidities, left atrial enlargement, left ventricular ejection fraction, and antiplatelet use, patients with AF precipitants were less likely to receive subsequent anticoagulation therapy at 30 days after the initial AF diagnosis (odds ratio, 0.31; 95% CI, 0.19-0.52). The association was persistent after excluding men with CHA₂DS₂-VASc score <2 and women with CHA₂DS₂-VASc score <3. Conclusions Our study highlights lower usage of oral anticoagulant in secondary AF in contemporary clinical practice.