Real-World Evidence Demonstrates an Appropriate Atrial Fibrillation
Population for Hybrid Convergent Approach versus Stand-Alone Cryoballoon
Ablation: A Long-Term Safety and Efficacy Study
Abstract
Introduction: A hybrid convergent approach (endocardial and
epicardial ablation) demonstrated superior effectiveness in a recent
randomized study for long-standing persistent atrial fibrillation
(LSPAF). Yet, there is a lack of real-world, long-term evidence as to
which patients are best candidates for a hybrid convergent approach
compared to standard endocardial cryoballoon pulmonary vein isolation
(CB PVI). Methods and Results: This single-center,
retrospective analysis spanning from 2010 to 2015 compared two
distinctly different atrial fibrillation (AF) cohorts; one treated with
stand-alone cryoablation and one treated with a hybrid convergent
approach. Baseline characteristics described candidates for each
approach. The following criteria were utilized to determine CB PVI
candidacy: 1) paroxysmal AF (PAF) with failed class I/III antiarrhythmic
drug (AAD) or 2) persistent/LSPAF with failed class I/III AAD unwilling
to undergo hybrid procedure. Selection criteria for the hybrid procedure
included: 1) PAF refractory to both class I/III AAD and prior CB PVI or
2) persistent/LSPAF with failed class I/III AAD agreeable to hybrid
procedure. Prior sternotomy was excluded. Serial electrocardiograms and
continuous monitoring evaluated primary efficacy outcome of
time-to-first recurrence of atrial arrhythmia after a 90-day blanking
period. Secondary outcomes were procedure-related complications and AAD
use (at discharge, 12, and 36 months). Kaplan-Meier methods evaluated
arrhythmia recurrence. Of 276 patients, 197 (64.2 ± 10.6 years old;
66.5% male; 74.1% PAF; 18.3% persistent AF; 1.0% LSPAF; 6.6%
undetermined) underwent CB PVI and 79 (61.4 ± 8.1 years old; 83.5%
male; 41.8% PAF; 45.5% persistent AF; 12.7% LSPAF) underwent hybrid
procedure. Arrhythmia freedom through 36 months was 55.2% for CB PVI
and 50.4% for hybrid (p =0.32). Class I AAD utilization at discharge
occurred in 38 (19.3%) patients in the CB PVI group and 5 (6.3%)
patients in the hybrid group (p=0.01). CB PVI class I AAD utilization at
12 months occurred in 14 (9.0) patients versus 0 patients for hybrid
convergent (p=0.004). Patients with one or more adverse event were as
follows: two (1.0%) in the CB PVI group (both transient phrenic nerve
palsy) and three (3.7%) in the hybrid group (two with significant
bleeding and one with wound infection) (p=0.14). Conclusion:
This study demonstrated that patients with more complex forms of AF (PAF
refractory to both AAD and index endocardial ablation or
persistent/LSPAF) could be well managed with a convergent approach.
Moreover, outcomes match safety and efficacy thresholds achieved by
patients with an early, less complex AF etiology treated by CB PVI
alone.