Importantly, despite a similar extent of LA enlargement/dysfunction and a lower LA afterload (i.e., lower E/e', lower BNP), patients with AF alone still manifested significantly larger LAWV and LAWT (SD) than patients with HFpEF alone after multiple adjustments (Table 2), indicating LA afterload might not be the single predominant pathological determinant driving greater wall thickness heterogeneity in isolated AF. The gene discussed is NPPB; the disease is atrial fibrillation.