Abstract 2027: Analysis of Outcomes Based on Left Ventricular Ejection Fraction in the Atrial Fibrillation Follow-Up Investigation of Rhythm Management Study
Background: The AFFIRM Study showed that treatment of patients with atrial fibrillation (AF) with a rhythm-control strategy offered no survival advantage over a rate-control strategy. Secondary analyses have shown that left ventricular (LV) dysfunction had a negative impact on survival for both treatment strategies.
Methods: A total of 4060 patients were enrolled (mean age, 69.7 ±9.0 years) of which 3311 (82%) underwent echocardiograms. Patients were subdivided into LVEF quartiles and EF ≥50% was considered normal. The primary endpoint was overall mortality. A composite secondary end point comprised of death, stroke, anoxic encephalopathy, major bleeding, and cardiac arrest. Mean follow-up was 3.5 years.
Results: LV function was abnormal in 26.0%. The mean LVEF was similar between the rate and rhythm-control groups (54.9 ±13.1% vs. 54.6 ±13.8%, p=0.74). Of the 2244 patients with normal LV function who were managed with a rate-control strategy, there were significantly lower rates of overall mortality (HR 0.79; 95% CI = 0.63–0.99, p=0.048) and the composite secondary endpoint (HR 0.80; 95% CI = 0.67 – 0.96, p=0.016). Of the 788 patients with abnormal LV function, there was no statistical difference in any of the LVEF quartiles between the two treatment strategies for overall mortality (p=0.54) or for the composite secondary endpoint (p=0.41).
Conclusions: Management of AF in patients with preserved LV function using a rate-control strategy conferred a statistically significant advantage for both overall survival and associated morbidity when compared to a rhythm-control strategy. This difference was not seen for those patients in other quartiles of abnormal LV function.