ISSN 2996-8215
International Journal of Cardiology | Vol. 6, No. 9, September 2015 | pp. 65–72
DOI: 10.46882/2015/IJC/000078
Original Research Article
Association Between Left Atrial Strain and Recurrence of Atrial Fibrillation Following Cryoballoon Catheter Ablation
Sven Lindstrom¹, Ingrid Johansson¹, Anders Nielsen²
¹Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden
²Department of Clinical Physiology, Aarhus University Hospital, Aarhus, Denmark
Abstract:
Cryoballoon catheter ablation is highly effective for achieving pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (AF), but anatomical left atrial (LA) diameter alone is a limited predictor of long-term rhythm stability. Left atrial reservoir strain (LA-RS) evaluated by speckle-tracking echocardiography provides a direct metric of structural tissue remodeling and wall compliance. This study investigated the independent association between baseline LA-RS and long-term arrhythmia recurrence following cryoballoon ablation. We prospectively followed 150 patients with symptomatic paroxysmal AF scheduled for cryoballoon catheter ablation. Transthoracic speckle-tracking deformation imaging quantified LA-RS prior to the intervention. The primary endpoint was any documented recurrence of atrial tachyarrhythmia lasting longer than 30 seconds after a 90-day post-ablation blanking period over a 24-month follow-up. Recurrent tachyarrhythmias occurred in 46 patients (30.7%). Baseline mean LA-RS was significantly lower in patients with recurrent events compared to those who maintained stable sinus rhythm (17.8% ± 3.1% vs. 27.8% ± 4.2%, p < 0.001). Multivariable Cox proportional hazards regression identified a depressed baseline LA-RS (absolute value less than 20%) as a powerful independent predictor of post-ablation AF recurrence (hazard ratio: 2.38, 95% CI: 1.32–4.35, p = 0.003), whereas conventional indexed left atrial volumes did not retain independent predictive significance. Left atrial reservoir strain is strongly and independently associated with atrial fibrillation recurrence following cryoballoon ablation, providing superior risk assessment compared to conventional volumetric parameters.
Keywords: Atrial fibrillation, Cryoballoon ablation, Speckle-tracking echocardiography, Left atrial strain, Recurrence, Structural remodeling
Received: June 05, 2015; Revised: July 18, 2015; Accepted: August 11, 2015; Published: September 15, 2015