How do we discover the unknown unknowns? Screening 'Well' patients after catheter ablation for atrial fibrillation

Abstract

This editorial refers to ‘Persistent iatrogenic atrial septal defect after pulmonary vein isolation by cryoballoon: an under-recognized complication’ by N-Y. Chan et al. , on page 1406. [T]here are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don't know we don't know. -Former US Secretary of Defense Donald Rumsfeld Atrial fibrillation (AF) remains a therapeutic challenge for millions of patients and their treating physicians. Advances in pharmacotherapy, including the development of novel antiarrhythmics1 and anticoagulants,2 have provided clinicians newer—but not necessarily better—treatment options for AF patients. There has been a concurrent evolution in catheter ablation for AF; novel ablation techniques have come, and in some cases gone,3 over the last several years. Whether these novel techniques will translate into improved safety and efficacy of AF ablation remains to be seen. While ablation modalities used in catheter-based therapy for AF are evolving, the physical introduction of those catheters into the left atrium (LA) remains a nearly universal constant. This is true for standard radiofrequency ablation approaches [i.e. wide, circumferential lesion sets to isolate the pulmonary veins (PV)], for more targeted LA ablation (of complex fractionated atrial electrograms, sympathetic ganglia, or putative rotors, for example), and for newer methods of achieving PV isolation (cryoablation, cyroballoon ablation, laser, microwave, robotically assisted catheter ablation, and so on). Each of these approaches relies on the delivery of one (and frequently more than one) catheter into the LA. …