Peak atrial longitudinal strain represents atrial fibrillation burden in daily practice: clinical implication of routine left atrial strain measurements

Background Usefulness of left atrial (LA) strain measurements using speckle tracking echocardiography has been reported in various clinical settings. However, clinical implication of routine LA strain measurements in daily practice remains unclear. The purpose of this study was to evaluate clinical utility of routine LA strain measurements in daily practice. Methods From January 6, 2020 to December 28, 2021, 338 consecutive patients underwent echocardiography in Takagi Cardiology Clinic, and all comers were enrolled to the study. Echocardiographic measurements including peak atrial longitudinal strain (PALS) measurement using speckle tracking echocardiography were attempted in all patients. Results PALS was obtained in 335 patients (age 71 +/- 16 years, male 43%, hypertensive 74%), and mean value was 22.3 +/- 11.5%. PALS was progressively impaired with worsening atrial fibrillation (AF) burden. PALS in patients without AF, in patients with history of AF (paroxysmal AF &/or ablation therapy), and in patients with AF onsite were 26.8 +/- 9.8%, 20.3 +/- 7.9%, and 8.1 +/- 3.3%, respectively (anova p < 0.0001). In patients without history of AF at the time of echocardiography, using cut-off value of 15.0% (i.e., mean + 2SD of PALS in AF patients), Kaplan-Meier analysis revealed that impaired PALS was associated with increased new-onset AF during follow-up period (log-rank p < 0.0001). Conclusion In daily practice, PALS represents AF burden. Furthermore, impaired PALS is associated with increased new-onset AF. Therefore, routine LA strain measurements using speckle tracking echocardiography will be useful in risk stratification of AF in daily practice.