An evaluation of atrial fibrillation begins with a medical history and physical examination.

Physical findings in those with atrial fibrillation may include:

• An irregular pulse
• A rapid pulse
• More severe cases may have findings associated with CHF:
• Low blood oxygen level
• Distended neck veins
• Enlarged liver
• Swelling of the feet and legs

Usually, testing is required to determine the cause of atrial fibrillation.

Tests that may be used to evaluate atrial fibrillation include:

• Pulse oximetry
• Blood electrolytes
• Cardiac enzymes
• Troponin levels
• Chest x-ray
• Echocardiogram
• Electrocardiogram (EKG or ECG)
• Cardiac monitoring
• Holter monitor
• Thallium heart scan
• Cardiac catheterization
• Thyroid profile
• Coagulation profile