Excessive consumption of vitamin K1-rich foods may antagonise the action of warfarin. Eating a large amount of brussels sprouts precipitated hospital admission for a patient who was on anticoagulation therapy for a left ventricular assist device. Doctors should counsel all patients in whom maintenance of anticoagulation is crucial against overconsumption of such foods.
A man in Scotland with chronic heart failure and severe left ventricular systolic dysfunction caused by coronary artery disease received a HeartMate II (Thoratec) left ventricular assist device (LVAD) as a bridge to transplantation. In line with standard practice, he was anticoagulated with warfarin. The target international normalised ratio (INR) was 2.0 (reference interval, 1.8–2.2). Stable anticoagulation was achieved with a daily dose of 7 mg.
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