Grant: Project Grant

Atrial fibrillation (AFib) is a common heart rhythm disorder. It affects quality of life and increases the risk of stroke and death. The name derives from the word fibrillation (quivering). Hence, AFib is the quivering of the upper chambers (atria) of the heart instead of a coordinated contraction, which causes an irregular heart rate. In most cases, abnormal electrical impulses that set off AFib come from the pulmonary veins. The pulmonary veins carry blood from the lungs to the left upper chamber (atrium) of the heart. Catheter ablation, a procedure used to remove faulty electrical pathways, has been developed to treat AFib. The procedure involves placing catheters (flexible wires) through veins in the groin. The catheters are advanced towards the heart, into the left atrium. Electric energy is then used to ablate (destroy) the atrial tissue around the pulmonary veins responsible for AFib. Although this intervention is effective for patients with intermittent episodes of AFib (80% success rate to prevent further episodes of AFib), it is not as good for patients with persistent AFib (episodes lasting >3 months) with success rates of 40-60%. We propose a study to see whether additional ablation in the atria (more than just around the pulmonary veins) could increase the success rate of ablation for patients with persistent AFib. We will compare 3 different ablation strategies. Patients will not know which one of the 3 procedures they receive. A total of 615 patients will be enrolled from 37 centers worldwide. Before ablation, patient medical history, routine exams and quality of life assessments will be completed. After the ablation, patients will be provided with a small portable device for weekly transmissions of heart rhythm during the study. After ablation, patients will be followed by the study doctor and research team at 3, 6, 9, 12 and 18 months. If our study shows that the additional ablation is better than standard ablation, it will become standard of care.