Clinical characteristics and outcomes of patients with atrial fibrillation: impact of an alternative primary diagnosis

Abstract

Objective To explore the impact of atrial fibrillation (AF) recognized at primary diagnosis on clinical features and outcomes of patients with AF in emergency service. Methods Data were collected from consecutive patients admitted in resuscitation room in the Department of Emergency (ED) of a major comprehensive teaching hospital, from January 1, 2011 through December 31, 2015. Patients were checked by electrocardiogram examination and / or monitored in resuscitation room after admission, and were divided into patients with AF recognized at a primary diagnosis and those with AF judged by alternative primary diagnoses in ED. The main criteria of prognosis were the length of resuscitation room stay, number of repeated ED visits, and outcome scale (such as death, transferred to intensive units, transferred to general wards, or direct discharge). Non-paired student t test, χ2, and circular distribution analysis were performed using SPSS 10.0 and EXCEL 2007 software. Results A total of 929 patients with mean age of (70.3±12.7)years, and 502 (54.0%) female were enrolled. There were 122 cases with AF not recognized at primary diagnosis but by an alternative primary diagnosis (non-primary group, NPG), and 807 cases with AF recognized at primary diagnosis (primary group, PG). Compared with the PG, the patients were older [(76.9±9.3)vs.(68.7±14.4), P<0.01], had more comorbidities [(1.75±1.26)vs.(0.08±0.39), P<0.01], higher APACHE Ⅱ scores [(17.89±8.19)vs.(8.64±4.15), P<0.01], longer resuscitation room stay (P<0.01), higher mortality (11.5% vs. 0.2%, OR=52.176, 95%CI: 11.698-232.710, χ2=78.928, P<0.01) and a higher percentage of transferring to intensive care unit (14.8% vs. 5.1%, OR=3.234, 95%CI: 1.791-5.838, χ2=16.674, P<0.01) in NPG. There were no significant difference in number of repeated-visits in ED between the PG and the NPG. Conclusion Patients with AF in the ED judged by alternative primary diagnosis are older and have more comorbidities, higher mortality and higher probability to be transferred to intensive care unit than patients with AF directly recognized by a primary diagnosis. This cohort of patients with special characteristics should be meticulously cared for and be distinguished from the patients with AF crystal clear at a primary diagnosis. Future studies are needed to examine the specific impact of AF on outcomes in the setting of primary diagnoses in ED. Key words: Atrial fibrillation; Emergency; Non-primary diagnosis; Mortality