The Bottom Line: Quality of life is determined by symptoms, sex, age and underlying disease severity, not by stringency or leniency of heart rate control.
Groenveld, Hessel. The effect of rate control on quality of life in patients with permanent atrial fibrillation: data from the RACE II (Rate Control Efficacy in Permanent Atrial Fibrillation II) study. Journal of the American College of Cardiology 2011 vol:58 iss:17 pg:1795 -1803
Symptoms of atrial fibrillation include palpitations, dyspnea, and fatigue. Patients with atrial fibrillation have a lower quality of life compared to healthy subjects; quality of life is restored and maintained by improvement of sinus rhythm. The RACE II trial showed lenient control is equally effective as strict control with respect to morbidity and mortality.