Interpret the Evidence
The Question Before the Drug: Rhythm Control Versus Rate Control
An antiarrhythmic is not chosen because it belongs to a particular Vaughan Williams class.
An antiarrhythmic is not chosen because it belongs to a particular Vaughan Williams class. It is chosen because the patient has a specific arrhythmia, clinical goal, substrate for proarrhythmia, organ function, and medication profile. In atrial fibrillation (AF), rate control and rhythm control answer different questions. Rate control limits ventricular response by slowing conduction through the AV node; it may improve palpitations, exercise tolerance, and haemodynamics while AF continues. Rhythm control attempts to restore and maintain sinus rhythm. It does not replace stroke-risk assessment or anticoagulation planning. For symptomatic established AF that remains inadequately controlled with rate control, rhythm control is recommended. For newly diagnosed AF, rhythm control should be considered. The target is not necessarily a completely AF-free monitor; meaningful success can be fewer symptoms, better cardiovascular outcomes, and less health-care use. [1] The experienced clinician first asks, “Is this patient unstable because of the rhythm?” A medication-selection discussion belongs only after that question is answered.