From Hip to Heart: Cobalt-induced Cardiomyopathy Requiring Cardiac Transplantation

Abstract

Cobalt toxicity is a rare cause of infiltrative cardiomyopathy. We describe a case of cobalt-induced cardiomyopathy that progressed to end stage heart failure requiring orthotopic heart transplantation. A 67 year old woman with history of bilateral cobalt-chromium hip replacements presented with dyspnea of 3 weeks duration. She was tachycardic and hypotensive, with elevated NT- proBNP. Electrocardiogram demonstrated sinus tachycardia, low voltage and right bundle branch block. Transthoracic echocardiogram revealed left ventricular ejection fraction of 20-25% with global hypokinesis and a moderate circumferential pericardial effusion. Left and right heart catheterization showed normal coronaries, elevated filling pressures and low cardiac index. Dobutamine infusion was initiated for management of cardiogenic shock. Cardiac magnetic resonance imaging (MRI) illustrated diffuse late gadolinium enhancement concerning for infiltrative cardiomyopathy. Extensive non-ischemic and rheumatologic workup was negative. Cobalt and chromium levels were significantly elevated at 121 mcg/L (Nl