Relation between Left Atrial Remodeling in Young Patients with Cryptogenic Stroke and Normal Inter-atrial Anatomy

Background and purpose: To investigate an association between left atrial (LA) structural and P wave dispersion (PWD) during sinus rhythm, and electrical remodeling in cryptogenic stroke (CS) patients.

Methods: Forty CS patients and 40 age- and sex-matched healthy controls were enrolled. P wave calculations were based on 12-lead electrocardiography (ECG) at a 50-mm/s-paper speed with an amplitude of 10 mm/mV. Difference between the maximum and minimum P wave duration was the P wave dispersion (PWD=Pmax-Pmin). LA deformation was evaluated by speckle tracking echocardiography within 3 days of the acute event.

Results: PWD was 30.1±7.0 ms and 27.4±3.5 ms in CS and control group (P=0.02), whereas LA maximum volume index [LAVImax] was 20.4±4.5 mL/m(2) and 19.9±2.4 mL/m(2) in CS and control group, respectively (P = 0.04). While global peak LA strain was [pLA-S] (LA reservoir function) 41.4 ± 6.3% and 44.5 ± 7.1% in CS and control group, (P = 0.04), global peak late diastolic strain rate values [pLA-SRa] (LA pump function) were 2.5 ± 0.4% and 2.9 ± 0.5% in CS and control group, respectively (P = 0.001). A mild and a strong negative correlation between global pLA-S and LAVImax (r=-0.49; P<0.01), and between PWD and global pLA-S (r = -0.52; P < 0.01), respectively, was observed in CS.

Conclusions: Increased PWD is associated with impaired LA mechanical functions and enlargement, and involved in the pathophysiology of AF or an AF-like physiology in CS.