Rate Control in Atrial Fibrillation: Many Questions Still Unanswered
More than 10 years ago seven rate versus rhythm control trials demonstrated that in patients with paroxysmal and persistent atrial fibrillation (AF) rate control was comparable to rhythm control regarding outcome.1,2 From that moment on, rate control became frontline therapy in older patients with few or acceptable symptoms of AF. Although being an easy to perform therapeutic strategy, rate control criteria as well as selection of drugs were not evidence based. Of interest, in the rate versus rhythm control trials rate controlling strategies differed significantly. Whereas The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial AFFIRM aimed to achieve heart rates comparable to the heart rates during sinus rhythm, patients included in the Rate Control versus Electrical Cardioversion for Persistent Atrial Fibrillation (RACE) study were treated with a more lenient approach. Thus far, only one randomized clinical trial has been performed evaluating different rate control strategies. The Rate Control Efficacy in Permanent Atrial Fibrillation: a comparison between Lenient and Strict Rate Control II (RACE II) study compared a strict rate control approach with a more lenient rate control approach in patients with permanent AF.3,4 The RACE II trial showed that a lenient rate control approach was not inferior as compared to a strict rate control approach regarding cardiovascular morbidity and mortality in patients with permanent AF without severe heart failure (HF). Subsequently, both the American College of Cardiology, American Heart Association, Heart Rhythm Society and the European Society of Cardiology guidelines adopted a lenient rate control approach as initial strategy in asymptomatic patients as long as the left ventricular function remains preserved.5,6 A more strict rate control approach, however, is recommended in more symptomatic patients or when left ventricular function deteriorates.
- Received September 9, 2015.
- Accepted September 10, 2015.