Predicting atrial fibrillation in cardiac amyloidosis: the role of left atrial deformation

Abstract Background Speckle-tracking echocardiography–derived left atrial (LA) strain parameters have emerged as reliable predictors of atrial fibrillation (AF) in the general population. Given the high prevalence of AF in patients with wild-type transthyretin amyloid cardiomyopathy (wtATTR-CM), early identification of individuals at elevated risk is essential. LA strain analysis may serve as a valuable noninvasive tool for this purpose. Objective To evaluate the predictive value of baseline LA strain parameters for the development of AF in patients with wtATTR-CM. Methods This retrospective, single-center study included patients diagnosed with wtATTR-CM between 2014 and 2024 who were in sinus rhythm at the time of diagnosis. Baseline echocardiographic assessment included Peak Atrial Longitudinal Strain (PALS), Peak Atrial Contraction Strain (PACS), and Peak Atrial Conduit Strain (PCS). The primary outcome was the incidence of AF during follow-up. Receiver operating characteristic (ROC) curves and Youden index were used to identify optimal cutoff values, and logistic regression was performed to evaluate predictive strength. Results Of 111 patients, 59 met inclusion criteria (73% male, mean age 80 ± 6 years). Over a median follow-up of 30 months [IQR 16–36], 30 patients (51%) developed AF. Patients who developed AF had significantly lower PALS (12.13 ± 4.76% vs. 15.22 ± 6.13%, p=0.034) and PACS (–6.29 ± 3.84% vs. –9.05 ± 5.54%, p=0.030). No significant difference was observed in PCS between groups (p=0.688). The optimal cutoff for PACS was –11.4%, which was significantly associated with AF occurrence (OR 7.368; 95% CI 1.449–37.462; p=0.016). PALS showed a trend toward significance at a cutoff of 14.6% (OR 0.339; 95% CI 0.114–1.008; p=0.052). Conclusion Among patients with wtATTR-CM, impaired LA strain—particularly reduced PACS—is significantly associated with the development of AF. While PALS also showed a predictive trend, PACS demonstrated stronger discriminative power. These findings support the incorporation of LA strain analysis into routine risk stratification protocols for AF in this population, warranting further validation in larger cohorts.