Drugs, the thyroid and the heart: a lethal cocktail

A 53 year old man was referred for evaluation of a raised International Normalised Ratio (INR) blood result. He had been taking warfarin and amiodarone for two years following a transient episode of atrial fibrillation following a percutaneous coronary interventional procedure. He was receiving treatment for severe left ventricular systolic dysfunction and Type 2 diabetes mellitus (Table 1). Initial evaluation revealed breathlessness at rest with evidence of decompensated cardiac failure (Figure 1, resting tremor, no thyromegaly, and he was unable to stand unaided.