Answer is B (Hypothroidism) Atrial Fibrillation is associated with hypehyroidism and not hypothyroidism Impoant causes of Atrial Fibrillation Cardiovascular causes of Atrial Fibrillation Rheumatic Hea disease (Includes mitral stenosis and mitral regurgitation) Non Rheumatic Mitral valve disease Chronic Hypeension Cardiomyopathy Myocarditis Pericarditis Congenital Hea Disease (eg ASD) Coronary Hea Disease Other Systemic Causes of AF Hypehroidism Pulmonary embolism Hypoxia Excess consumption of alcohol (Also alcohol withdraw) Excess consumption of Caffeine May be seen in normal individuals Paicularly during emotional stress or following surgery, exercise or prominent surge of vagal tone (vasovagal response) AF often develops in patients with hea or lung disease who develop hypoxia, hypercapria or metabolic or hemodynamic derangements Holiday Hea Syndrome: In predisposed individuals, AF may be precipitated by consumption of even small amounts of alcohol. This is called Holiday Syndrome and is usually transient and self limited