• Rate control can be started in primary care, but rhythm control should only be started following specialist assessment.
• Rate control is the preferred treatment for permanent atrial fibrillation (AF) and in people with persistent AF and any of the following:
• More than 65 years of age.
• With coronary artery disease.
• With contraindications to antiarrhythmic drugs.
• Unsuitable for cardioversion.
• Rhythm control is the preferred treatment for paroxysmal AF and in people with persistent AF and any of the following:
• Symptomatic.
• 65 years of age or less.
• Presenting for the first time with lone AF.
• Presenting with AF secondary to a treated or corrected precipitant (such as infection).
• With congestive heart failure.
• If there is uncertainty about which option is best (for example the person may be older than 65 years of age with lone AF), seek specialist advice.

• Rate control involves the use of drugs to slow the ventricular heart rate, in an attempt to minimize symptoms and associated morbidity of atrial fibrillation (AF). Rate control will not stop the atria from fibrillating.
• Rhythm control involves the use of drugs to maintain normal sinus rhythm once AF has terminated (spontaneously or after electrical or pharmacological cardioversion). Rhythm control is often needed long term to help prevent recurrence of AF.
• Cardioversion is unsuitable for people with:
• Contraindications to anticoagulation.
• Structural heart disease (for example a large left atrium greater than 5.5 cm or mitral stenosis) that makes it unlikely that sinus rhythm would be maintained following successful cardioversion. 
• A long duration of AF (usually greater than 12 months).
• A history of multiple failed attempts at cardioversion and/or relapses, even with concomitant use of antiarrhythmic drugs or non-pharmacological approaches.
• An ongoing but reversible cause of AF, until the precipitant has been effectively treated (such as thyrotoxicosis).

These recommendations are based on the National Institute for Health and Clinical Excellence (NICE) guideline Atrial fibrillation: national clinical guideline for management in primary and secondary care [National Collaborating Centre for Chronic Conditions, 2006].

• After reviewing the evidence (five randomized controlled trials and one meta-analysis) comparing rate control with rhythm control on different outcomes, NICE concluded that overall there is no difference between rhythm control and rate control in terms of mortality or quality of life.
• NICE states that rate control is the preferred treatment in people with permanent AF (as by definition rhythm control has been tried and failed, or is not an option), and in people with persistent AF who are older than 65 years of age, have evidence of coronary heart disease, or have no evidence of heart failure, as there is some evidence that rate control may be superior in these groups.
• In one study, there was a significant difference in favour of rate control in terms of all-cause mortality in people older than 65 years of age and in people with coronary artery disease.
• In three studies, rhythm control compared with rate control resulted in a higher rate of adverse effects and hospital admissions and a higher incidence of arrhythmias in people with recurrent AF.
• In one study, rhythm control was associated with a lower incidence of all-cause mortality in people with heart failure.
• However, CKS found a subsequent prospective, open-labelled trial (n = 1376) with 2 years of follow-up which suggests that in people with AF and symptoms of heart failure, rhythm control and rate control may result in similar cardiovascular outcomes [Roy et al, 2008].