An 84-year-old woman was admitted to the hospital because of fever, wheezing, and shortness of breath. She had a history of hypertension, chronic atrial fibrillation, chronic obstructive pulmonary disease, and hypothyroidism that was attributed to the use of amiodarone (Cordarone, Pacerone). Her medications on admission were levothyroxine (Synthroid), short-acting β agonists, ipratropium (Atrovent), enalapril (Vasotec), and aspirin.

An electrocardiogram showed atrial fibrillation, with a ventricular rate of 108 beats/minute, right bundle- branch block, and ectopic ventricular beats. A chest x-ray showed mild cardiomegaly and peripheral infiltrates in the upper lobe of the left lung and the lingula. Laboratory tests showed the following values: hematocrit, 38%; white blood cell count, 17,300/mm³; platelet count, 140,000/mm³; sodium, 134 mmol/L; potassium, 4.2 mmol/L; and glucose, 147 mg/dL. An acute exacerbation of her symptoms because of pneumonia due to Haemophilus influenzae was diagnosed, and the patient was treated with ceftriaxone (Rocephin) 1 g twice a day plus levofloxacin (Levaquin) 500 mg/day.

According to the results of our study, this patient would benefit from treatment with antithrombotic agents. Given her age and comorbid conditions, the benefits of long-term antithrombotic treatment were determined to outweigh the risks for this patient.