Management of increased response to warfarin associated with decompensated heart failure in an outpatient family medicine clinic

Abstract

We report a 55-year-old patient with left ventricular heart failure and an ejection fraction of < 10% that was placed on warfarin therapy (42 mg/week) for the presence of a left ventricular thrombus.  Thirty-nine days after hospital discharge, the patient presented with complaints of increased dyspnea over the previous week and required a wheelchair for mobility. The patient’s weight had increased by 28 lbs (13 kg).  As the patient’s weight increased, his dose requirements for warfarin decreased resulting in an almost 30% reduction in his warfarin dose.  Two months after the initiation of metolazone therapy, the patient lost 53 lbs (24 kg) and his warfarin requirements increased eventually placing him on his original prescribed dose of 42 mg/week. This case shows that if a patient’s decompensated heart failure can be controlled with few exacerbations and close monitoring, they can be safely managed on warfarin in an outpatient setting.