Several factors have been related to the presence of paroxysmal AF, including older age, female sex, previous history of hypertension, thyroid pathology, chronic obstructive pulmonary disease (COPD), heart failure or ischemic heart disease, higher National Institutes of Health Stroke Scale (NIHSS) score, left atrial enlargement, P-wave duration and morphology, brain natriuretic peptide, and HDL-cholesterol concentrations (7, 8). The gene discussed is NPPB; the disease is thyroiditis.