Reversal of Atrial Substrate to Prevent Atrial Fibrillation Pilot Study

Atrial fibrillation (AF) is a major health problem, with a prevalence of 0.4-1% of the population. It is associated with a six-fold risk of stroke and a two-fold increase in mortality, the main cardiac reason for death one year after presenting to the emergency department with AF is heart failure. It results in high healthcare costs, recurrent ED visits and hospitalizations. The burden of disability associated with AF has been found to increase by 20% from 1990-2010. AF was also cited as one of the seven causes of death that has been increasing worldwide. Prevention of AF has not been a focus of past treatments and it is well known that elevated body mass index, hypertension, smoking, increased alcohol intake, lack of exercise and sleep apnea are risk factors for AF. There is a lack of randomized, multicenter data proving that a strategy of aggressive risk factor modification will prevent and modify AF.

Upstream therapy for AF has been of considerable interest, and benefit has been demonstrated in primary prevention of AF. Catheter ablation has demonstrated success over current medical therapies for long-term rhythm control, but recurrence remains high, irrespective of ablation strategy. This study is a feasibility study to determine whether a complex and multi-component risk factor modification can be successfully implemented.

Inclusion criteria

• Patients with symptomatic (CCS-SAF ≥2) recurrent paroxysmal or persistent nonvalvular atrial fibrillation despite rate control, desiring catheter ablation AND
• one of : BMI>27, BP>140/90 or history of hypertension, alcohol use > recommended limit, current smoking, diabetes with HgA1C>7%, physical inactivity (<150 minutes/week).

(Definitions: Recurrent paroxysmal - at least 4 episodes of symptomatic AF in the prior 6 months, with or without cardioversion; Persistent AF lasting greater than 7 days but less than 3 years; AF must be documented on a Holter, rhythm strip or electrocardiogram within the last 24 months.)

Exclusion criteria

• Permanent AF (AF lasting > 3 years)
• Prior catheter ablation for AF
• Left ventricular ejection fraction <30%
• Left atrial size > 5.5 cm
• NYHA IV heart failure
• Participation in a cardiac rehabilitation program within the last year
• Currently performing exercise training 150 minutes/week of moderate to vigorous physical activity
• Unable to exercise
• Unable to give informed consent
• Other noncardiovascular medical condition making 1 year survival unlikely