Surgical Ablation of AF Efficacy Trial

Atrial fibrillation (AF) affects more than 1% of the general population and is an important risk factor for stroke. AF prevalence increases with age, occurring in 10 to 15% of patients older than 80 years of age, which is important with the aging population. Of patients undergoing cardiac surgery, 10.8% have a history of AF. AF is believed to cause the left atrium to dilate and lose its transport function. AF significantly increases the risk of ischemic stroke of cardioembolic origin, but is also associated with heart failure and impairs quality of life. Although the causal relationship between the 2 clinical entities has not been fully elucidated, AF is believed to cause heart failure via several mechanisms.

Ablation of AF is the application of scars to the atrial tissue to disrupt faulty electrical signals that cause the arrhythmia. If surgical ablation of AF yields a benefit similar to catheter-based AF ablation, thousands of people undergoing cardiac surgery could benefit from this procedure each year. SAFE will be a landmark trial in cardiac surgery, definitely establishing surgical AF ablation's impact on cardiovascular outcomes. Cardiac surgery is the optimal setting to establish whether maintenance of sinus rhythm through AF ablation yields clinical benefit, and is a setting where sham-control is possible. This will not only provide evidence for the cardiac surgical patients but will bolster the evidence for ablation (catheter or stand-alone surgical) in other AF patients.

The intervention under investigation is concomitant surgical AF ablation which is compared to no surgical AF ablation. The primary outcome is hospital readmissions with heart failure during 4 years of follow-up. This study will enroll 2000 patients from 50 centres, globally. Patients will be followed at hospital discharge, 4 to 6 weeks after surgery, 6 months after surgery, and then at 6-month intervals until the final follow-up visit, for a median follow-up for 4 years.

• Number of Ischemic stroke or systemic arterial embolism events over duration of follow up [Time frame: Common termination point for trial (median follow-up of 4 years)]
• Length of ICU stay [Time frame: From the date of study intervention surgery completion to the date of index hospital discharge, assessed up to the common termination point for trial (median follow-up of 4 years)]
• Length of hospital stay [Time frame: From the date of study intervention surgery completion to the date of index hospital discharge, assessed up to the common termination point for trial (median follow-up of 4 years)]
• Freedom from recurrence of atrial tachyarrhythmia [Time frame: 1 year post-operatively]
• Number of days free from admission to healthcare facility or presentation to the emergency department for heart failure [Time frame: Common termination point for trial (median follow-up of 4 years)]
• All-cause mortality [Time frame: Common termination point for trial (median follow-up of 4 years)]
• Cardiovascular mortality [Time frame: Common termination point for trial (median follow-up of 4 years)]
• Antiarrhythmic drug use [Time frame: Beyond 6 weeks until common termination point for trial (median follow-up of 4 years)]
• Number of patients undergoing atrial fibrillation ablation [Time frame: 90 days post- study surgery until common termination point for trial (median follow-up of 4 years)]
• Quality of Life - atrial fibrillation specific [Time frame: At 1 year, and at common termination point for trial (median follow-up of 4 years)]
• Quality of Life - heart failure specific [Time frame: At 1 year, and at common termination point for trial (median follow-up of 4 years)]
• Quality of Life - General [Time frame: At 1 year, and at common termination point for trial (median follow-up of 4 years)]