• Randomized, multicenter, unblinded trial
• 1376 patients, ≥ 18 years with documented LVEF ≤ 35% (by nuclear imaging, echo or cardiac angiography) and a history of both:
  • atrial fibrillation = one episode lasting ≥ 6 hours or cardioversion within the last 6 months or an episode lasting ≥ 10 minutes in the last 6 months and previous electrical conversion
  • Heart failure = NYHA class II-IV symptoms in the last 6 months, asymptomatic with either HF hospitalization in the last 6 months or LVEF ≤ 25%.
• For all patients, recommendations for ACE inhibitor or ARB therapy; maximum tolerated doses of beta-blockers; anticoagulation. Recommendations for implantable defibrillator and ventricular-resynchronization as per guidelines.

• persistent AF >12 months, AF or HF with reversible etiology, use of antiarrhythmic drugs for other arrhythmias, 2° and 3° AV block, HF decompensation within 48 hrs of randomization, previous AV nodal ablation, long-QT syndrome, planned cardiac transplant, dialysis patients

• Rhythm Control arm: Initial therapy with amiodarone and either sotalol or dofetilide if required. Electrical cardioversion was performed within 6 wks of randomization if patients did not convert to sinus rhythm after antiarrhythmic drug therapy; if needed, a second cardioversion was performed within three months and for subsequent AF recurrences. Pacemakers were recommended if bradycardia prevented use of antiarrhythmics.
• Rate Control arm: Titrated beta-blocker with digitalis to achieve target resting heart rate <80 bpm and 6 minute walk test HR <110 bpm. AV nodal ablation and pacemaker therapy were recommended if rate control was not achieved with drugs.

Primary Endpoints

Death from cardiovascular causes: 27% (rhythm-control) vs. 25% (rate-control); unadjusted hazard ratio 1.06 (0.86-1.30), p=0.59.

Secondary Endpoints (see study for complete list)

Rhythm Control	Rate Control	Hazard Ratio	p
All cause mortality
32%	33%	0.97 (0.80-1.17)	0.73
Stroke
3%	4%	0.74 (0.40-1.35)	0.32
Worsening HF (hospitalization required, IV diuretics, change in treatment strategy)
28%	31%	0.87 (0.72-1.06)	0.17
Composite of death from CV causes, stroke, worsening HF
43%	46%	0.90 (0.77-1.06)	0.20

• increased hospitalization in the rhythm-control group (64%) than in the rate-control group (59%), p=0.06
• increased hospitalization for AF in the rhythm-control group (14%) than in the rate-control group (9%), p=0.001
• increased hospitalization for bradyarrhythmias in the rhythm-control group (6%) than in the rate-control group (3%), p=0.02