A 78-year-old woman suffered from a myocardial infarction while being treated in hospital for hip fracture. Coronary angiography showed three-vessel coronary artery disease. She underwent bypass surgery. Five days after the operation she is complaining of palpitation and dyspnea:

• Atrial flutter with 2:1 AV block
• Ventricular rate 143/min
• Left ventricular hypertrophy with repolarization abnormality

When the heart rate is close to 150/min and there are negative P waves in the inferior leads, atrial flutter with 2:1 AV block is a strong possibility.