Genetically elevated Lp(a) was inversely associated with the risk of atrial fibrillation [odds ratio (OR), 0.94; 95% confidence interval (95%CI), 0.901–0.987; P = 0.012)], the risk of arrhythmia (OR, 0.96; 95%CI, 0.941–0.990; P = 0.005), the left ventricular mass index (OR, 0.97; 95%CI, 0.949–1.000; P = 0.048), and the left ventricular internal dimension in diastole (OR, 0.97; 95%CI, 0.950–0.997; P = 0.028) according to the inverse-variance weighted method. The gene discussed is LPA; the disease is atrial fibrillation.