Long-Standing Persistent AF
The progression of AF from paroxysmal to long-standing persistent AF is characterized by advanced substrate remodeling of the left atrium in a stretch, inflammation, and fibrosis sequence leading to fibrillation.25 Thus, in advanced AF, the predominant triggers have evolved from the pulmonary vein to left atrial tissue, particularly on the posterior wall, creating a need for treatment options beyond endocardial ablation to effectively and comprehensively treat long-standing persistent AF.26,27Success rates of endocardial ablation in this population have had limited effectiveness, ranging from 35.6 to 43% after a single procedure.26,27This is attributed to the lack of a standardized lesion set, limited ability to produce transmural lesions, and dissociation of electrical activity between the endocardium and epicardium. A subgroup analysis examining the effectiveness of the Hybrid Convergent procedure for long-standing persistent AF demonstrated an absolute difference of 28.8% (78% improvement; p=0.022) in 12-month freedom from AF in the Hybrid group over the endocardial only group and was sustained through 18-months.28 The benefit of Hybrid Convergent held when compared to the Catheter Ablation arm and their respective impacts on AF burden reduction as well as freedom from cardioversion and AF symptoms, through 18-months. Along with an acceptable safety profile, these significantly improved outcomes provided the collaborative heart team a new, effective approach for the difficult to treat population of patients suffering from advanced AF.