Characteristics and Outcomes of Concurrently Diagnosed New Rapid Atrial Fibrillation or Flutter and New Reduced Ejection Fraction

BACKGROUND: Characteristics and outcomes of concurrently diagnosed new rapid atrial fibrillation (AF) or atrial flutter (AFL) and new heart failure with reduced left ventricular ejection fraction (LVEF) are not well described. METHODS: A retrospective cohort study of subjects referred for expedited transesophageal echocardiography-guided rhythm-control strategies for concurrent new rapid AF/AFL and new LVEF ≤ 40% diagnosed during the same admission was analyzed. RESULTS: -VASc = 2) presented with new AF (n = 18) or AFL (n = 7) with rapid ventricular rate (median 135 beats/min) and new reduced LVEF (median 27%; range, 10-37.5%). Seven (28%) subjects had left atrial appendage thrombi (LAAT) and five (20%) subjects had heavy or binge alcohol use. Baseline characteristics were similar between those with and without LAAT. Thirteen subjects with AF and without LAAT underwent direct-current cardioversion (DCCV) and 10 (77%) had AF recurrence within 90 days. Improvement of long-term LVEF to >40% was comparable for subjects with and without initial LAAT (83% vs 94%; P = 0.46). Three of four subjects who received primary prophylaxis implantable cardioverter-defibrillators improved their LVEF to >35% after sinus rhythm maintenance. The median long-term follow-up time was 3.0 years. CONCLUSIONS: Subjects with concurrently diagnosed new rapid AF/AFL and new reduced LVEF are characterized by a high prevalence of LAAT and significant alcohol use. AF subjects without initial LAAT who underwent DCCV had a high 90-day AF recurrence rate. The presence of LAAT did not have a prognosticative effect on eventual LVEF improvement, which was observed in almost all subjects.