Catheter-based ablation of atrial fibrillation (AF) is an established treatment option for symptomatic patients who are refractory to drug-based treatment, as implemented in the latest guidelines for the management of AF.1 The accepted and recommended cornerstone of all ablation strategies for AF is electrical isolation of the pulmonary veins (PV).2 However, in addition to PV isolation (PVI), ablation strategies for persistent or even long-standing persistent AF are heterogeneous. They may be characterised by PVI as the sole ablation target but can be extended to ablation of complex fractionated atrial electrograms (CFAE) and/or linear lesions.3–6 The recently published prospective, randomised, multicentre Substrate and Trigger Ablation for Reduction of Atrial Fibrillation (STAR-AF II) study demonstrated that pure PVI in patients with persistent AF is not less effective than more extensive ablation strategies such as ablation by way of linear lesions (mitral isthmus line and roof line) or ablation of CFAE.7
In this regard the second-generation cryoballoon has proven its potential for safe, effective and time-efficient PVI. One-year clinical outcome success after cryoballoon-based PVI in patients with paroxysmal AF (PAF) ranges between 80 % and 90 %.8–10 Cryoballoon-based PVI is also starting to demonstrate encouraging results in persistent AF; however these findings need further evaluation.11,12 In addition, novel invasive and non-invasive mapping systems allowing for focal impulse and rotor mapping (FIRM) are under investigation; they will broaden our comprehension of the underlying pathophysiology of AF and might potentially extend or change our ablation options and strategies in PAF as well as in persistent AF.13–16