Habitual aerobic exercise is associated with left atrial (LA) enlargement which may increase risk of atrial fibrillation. Patients with LVH and increased LV stiffness may be more predisposed to LA remodeling due to higher LA pressures during exercise. We tested the hypothesis 1 year of aerobic exercise training would increase LA size to a greater extent in patients with LVH than controls. Adults with LVH (n=53) enriched for increased cardiac risk and LV stiffness and control (CON) subjects (n=58) were randomized to one year of high intensity aerobic exercise (ex) or yoga control. LA and LV volumes were measured using 3D echo. Of 111 participants, 83 had complete data available (LVH: 18 exercisers, 10 yoga
CON: 29 exercisers, 26 yoga). Baseline LA volume indices were similar between groups (LVH: 19.8 ± 4.4 mL/m