Increased left atrial pressure in non-heart failure patients with subclinical hypothyroidism and atrial fibrillation

Background The impact of subclinical hypothyroidism on the cardiovascular risk is still debated. We aimed to measure the relationship between subclinical hypothyroidism and the left atrial (LA) pressure. Methods The LA pressures and thyroid function were measured in consecutive patients undergoing atrial fibrillation (AF) ablation, who did not have any known heart failure, structural heart disease, or overt thyroid disease. Results Subclinical hypothyroidism (4.5≤ thyroid-stimulating hormone 18 mmHg (odds ratio 3.94, 95% CI 1.28 11.2; P = 0.02). Conclusions Subclinical hypothyroidism may increase the LA pressure in AF patients.