Tailored Cryoballoon Pulmonary Vein Ablation for Atrial Fibrillation: When to Stop the Freeze?

Atrial fibrillation (AF) is the most common cardiac arrhythmia with an increasing prevalence and burden on the health care system [ [1] Gallagher C. Hendriks J.M. Giles L. Karnon J. Pham C. Elliott A.D. et al. Increasing trends in hospitalisations due to atrial fibrillation in Australia from 1993 to 2013. Heart. 2019; 105: 1358-1363 Google Scholar , [2] Wong C.X. Brown A. Tse H.F. Albert C.M. Kalman J.M. Marwick T.H. et al. Epidemiology of atrial fibrillation: the Australian and Asia-Pacific perspective. Heart Lung Circ. 2017; 26: 870-879 Google Scholar ]. Recently, comprehensive lifestyle and risk factor modification have been shown to reduce AF burden but there has been no new anti-arrhythmic drug discovery for many years [ [3] Gallagher C. Fitzgerald J.L. Stokes M.B. Noubiap J.J. Elliott A.D. Hendriks J.M. et al. Risk factor management in atrial fibrillation: how to deliver a successful clinic. Curr Cardiovasc Risk Rep. 2021; 15: 9 Google Scholar ]. Catheter ablation remains an attractive strategy to combat AF in patients with symptomatic AF despite lifestyle and pharmacological therapy. Although our understanding of the pathophysiological mechanisms underlying AF has improved, pulmonary vein isolation (PVI) remains the gold standard in catheter-based therapy for this complex arrhythmia as recent research aimed at targeting putative AF drivers has not shown significant incremental improvement in achieveing freedom from AF [ [4] Lau D.H. Linz D. Schotten U. Mahajan R. Sanders P. Kalman J.M. Pathophysiology of paroxysmal and persistent atrial fibrillation: rotors, foci and fibrosis. Heart Lung Circ. 2017; 26: 887-893 Google Scholar ]. More recent data has demonstrated the potential merits of cryoballoon PVI over anti-arrhythmic drugs even as a first-line option in those with symptomatic paroxysmal AF [ [5] Andrade J.G. Wells G.A. Deyell M.W. Bennett M. Essebag V. Champagne J. et al. Cryoablation or drug therapy for initial treatment of atrial fibrillation. N Engl J Med. 2021; 384: 305-315 Google Scholar , [6] Wazni O.M. Dandamudi G. Sood N. Hoyt R. Tyler J. Durrani S. et al. Cryoballoon ablation as initial therapy for atrial fibrillation. N Engl J Med. 2021; 384: 316-324 Google Scholar ]. Indeed, there has been a worldwide growth in the uptake of cryoballoon PVI for AF since the initial ‘FIRE AND ICE’ 1 A Controlled, Prospective, Non-Inferiority, Parallel-Group, Randomised, Interventional, Open, Blinded Outcome Assessment (PROBE-Design), Multi-centre Trial, Comparing Efficacy and Safety of Isolation of the PVs With a Cryoballoon Catheter vs a Radiofrequency Ablation With a ThermoCool Catheter in Patients With PAF. trial demonstrated non-inferiority of cryoballoon to conventional radiofrequency point-by-point ablation for PVI, with regard to efficacy and safety endpoints in those with drug-refractory paroxysmal AF [ [7] Kuck K.H. Brugada J. Furnkranz A. Metzner A. Ouyang F. Chun K.R. et al. FIRE AND ICE InvestigatorsCryoballoon or radiofrequency ablation for paroxysmal atrial fibrillation. N Engl J Med. 2016; 374: 2235-2245 Google Scholar ]. Further, compared to radiofrequency ablation, cryoballoon PVI was found to be associated with shorter procedure time as well as lower resource utilisation and costs, due to fewer repeat ablations and reduced cardiovascular re-hospitalisations [ [7] Kuck K.H. Brugada J. Furnkranz A. Metzner A. Ouyang F. Chun K.R. et al. FIRE AND ICE InvestigatorsCryoballoon or radiofrequency ablation for paroxysmal atrial fibrillation. N Engl J Med. 2016; 374: 2235-2245 Google Scholar , [8] Chun K.R.J. Brugada J. Elvan A. Geller L. Busch M. Barrera A. et al. FIRE AND ICE InvestigatorsThe impact of cryoballoon versus radiofrequency ablation for paroxysmal atrial fibrillation on healthcare utilization and costs: An economic analysis from the FIRE AND ICE trial. J Am Heart Assoc. 2017; 6 Google Scholar ]. New Minimally Invasive and Tailor-Made Strategy for Cryoballoon Ablation in Patients With Paroxysmal Atrial FibrillationHeart, Lung and CirculationVol. 31Issue 4PreviewThe optimal dosage for cryoballoon ablation (CBA) of atrial fibrillation (AF) is still unknown. Full-Text PDF