Cryoablation for paroxysmal and persistent AF in patients with structural heart disease and preserved ejection fraction: Clinical outcomes from 1STOP, a multicenter observational project.

BACKGROUND

Pulmonary vein isolation (PVI) is an accepted strategy for paroxysmal atrial fibrillation (PAF) and persistent AF (PerAF) ablation. Limited data are available on outcomes of cryoballoon (CB) PVI in patients with structural heart disease (SHD). The purpose is to assess the clinical efficacy of a single CB-PVI procedure in patients with PAF or PerAF who also have SHD.

METHODS

From April 2012, 460 AF patients with concomitant SHD underwent CB-PVI and were followed prospectively in the framework of the 1STOP ClinicalService® project. Data on procedural outcomes and long-term freedom from AF recurrence were evaluated. Out of 460 subjects, 282 patients (61%) had PAF and 178 (39%) PerAF.

RESULTS

SHD patients were predominantly male (80.9%), old (62.8±8.9 years), with preserved functional capacity (New York Heart Association class >1: 39.4%), high cardioembolic risk (CHA2DS2VASc score ≥2: 69.3%), and conserved left ventricular ejection fraction (56.5±8% LVEF). Both subjects with PAF and PerAF had similar baseline clinical characteristics except for left atrial diameter (43.8±7 vs. 45.7±7mm) and area (22.9±5.2 vs. 25.1±4.4cm2), respectively. Procedure time and fluoroscopic time as well as the rate of procedural complications were not different between subjects with PAF and PerAF. After a mean follow-up of 12 months, antiarrhythmic drug therapy had dropped from 71.7% before ablation to 33.6% post-ablation (p<0.001) and the freedom from symptomatic AF recurrence was 78% for PAF and 77% for PerAF (p=0.793). Furthermore, atrial arrhythmia recurrence rate was not related to SHD.

CONCLUSIONS

In a large multicenter, real-world cohort, CB-PVI was used to treat patients with PAF and PerAF who also had SHD. The arrhythmia recurrence after a single procedure was not related to either the degree of cardiac structural remodeling or the type of AF, and the rate of AF recurrence was lower than previously reported in patients with SHD in other cohort series using focal radiofrequency catheter ablation.

CLINICAL TRIAL REGISTRATION: clinicaltrials.gov (NCT01007474).