Left atrial strain as a noninvasive marker of atrial fibrosis in patients undergoing high-power short-duration AF ablation
I A Minciuna, G Cismaru, R Tomoaia, N C Hart, A M Linul, M Puiu, G Simu, R O Rosu, D PopAbstract
Background
Atrial fibrosis represents the structural substrate underlying atrial fibrillation (AF) maintenance and recurrence after catheter ablation (CA). Low-voltage areas (LVAs) identified during electroanatomical voltage mapping accurately reflect fibrotic remodeling and provide an invasive marker for substrate characterization. Left atrial (LA) strain assessed by speckle-tracking echocardiography offers a noninvasive evaluation of atrial compliance and function, potentially serving as a surrogate marker for atrial fibrosis.
Purpose
To evaluate the relationship between echocardiographic LA strain parameters and the extent of fibrosis detected by voltage mapping in patients undergoing high-power short-duration (HPSD) CA for AF.
Methods
Twenty-eight consecutive AF patients (67.9% male, mean age 64 ± 7.9 years) were prospectively enrolled. Paroxysmal AF was present in 39.3% and persistent in 60.7%. Mean LA diameter was 45 ± 7.2 mm and LA volume 84.9 ± 29.4 mL. LA reservoir and contraction strain were assessed by 2D speckle-tracking (mean values 18.6 ± 10.9% and 7.6 ± 6.7%, respectively). During ablation, voltage maps were acquired, and LVAs (<0.5 mV) were considered fibrotic. Fibrosis was identified in 10 patients (35.7%), with a mean area of 4.1 ± 8.5 cm².
Results
Reduced LA reservoir strain correlated with lower contraction strain (R = 0.44, p = 0.02), higher LA volume (R = 0.68, p < 0.001), and larger fibrosis area (R = 0.59, p = 0.01). Contraction strain also correlated with LA volume (R = 0.68, p < 0.001) and fibrosis (R = 0.48, p = 0.08). Patients with LVAs had significantly lower LA reservoir and contraction strain compared with those without fibrosis.
Conclusion
Left atrial strain, particularly reservoir strain, shows a strong relationship with fibrotic burden assessed by voltage mapping during AF HPSD CA. Echocardiographic strain analysis offers a simple, reproducible, and noninvasive tool for estimating atrial fibrosis. Incorporating LA strain into pre-ablation evaluation may improve patient selection, procedural planning, and prediction of ablation outcomes in atrial fibrillation.