CardioNerds (Amit Goyal) join Dr. Merna Hussien, Dr. Akhil Kallur, Dr. Abhinav Saxena, and Dr. Brody Deb from the MedStar Georgetown – Washington Hospital Center in DC for a stroll around Rock Creek Park as they discuss an unusual case of cobalt cardiomyopathy. Expert commentary is provided by Dr. Nana Afari Armah. Episode audio was edited by CardioNerds Intern Christiana Dangas.
The case is of a middle-aged woman with a past medical history of hypertension, hyperlipidemia, and bilateral hip replacements, who presented with subacute progressive exertional dyspnea, orthopnea, and constitutional symptoms and was found to have SCAI Stage C cardiogenic shock. Transthoracic echocardiogram showed severely reduced left ventricular ejection fraction (LVEF, 20-25%) and a moderate pericardial effusion. Cardiac catheterization revealed biventricular failure with elevated filling pressures. A cardiac MRI showed diffuse late gadolinium enhancement (LGE) in the left ventricle. Endomyocardial biopsy showed nonspecific chronic inflammation. However, the evidence of mitochondrial heavy metal toxicity and elevated cobalt levels made the diagnosis of cobalt cardiomyopathy. The patient underwent revision of hip joint implants to ceramic implants and started chelation therapy. However, due to persistent stage D heart failure despite normalization of cobalt levels, she underwent orthotropic heart transplantation.
“To study the phenomena of disease without books is to sail an uncharted sea, while to study books without patients is not to go to sea at all.” – Sir William Osler. CardioNerds thank the patients and their loved ones whose stories teach us the Art of Medicine and support our Mission to Democratize Cardiovascular Medicine.
A good history goes a long way in diagnosing non-ischemic cardiomyopathy (NICM).
Common problems can have uncommon presentations requiring a high degree of suspicion for diagnosis.
Imaging features can overlap between causes of NICM. History helps in targeting further histological workup and uncovering the root cause.
Multidisciplinary effort is essential in making a rare diagnosis.
Taken from1 – Singh M, Krishnan M, Ghazzal A, Halushka M, Tozzi JE, Bunning RD, Rodrigo ME, Najjar SS, Molina EJ, Sheikh FH. From Hip to Heart: A Comprehensive Evaluation of an Infiltrative Cardiomyopathy. CJC Open. 2021 Nov 1;3(11):1392–5.
Notes – Cobalt Cardiomyopathy
How common is cobalt cardiomyopathy? When should it be suspected?
Cobalt cardiomyopathy is incredibly rare, with only a handful of reported cases. 2 It is also known as beer drinkers’ cardiomyopathy, as cobalt was added to beer for fortification in Quebec 3, where it was first reported. Cobalt cardiomyopathy is characterized by its rapidly progressive nature, the presence of low voltages on EKG, and diffuse infiltration. Patients also complained of a previous history of anorexia and weight loss and were found to have polycythemia and thyroid abnormalities on labs. This syndrome was very similar to wet beriberi except for the absence of a therapeutic response to thiamine.
Taken from – 2
Later, this was noted in patients with total metal hip arthroplasty 4–6, especially in patients with metal-on-metal hip arthroplasty, which led to corrosion and leakage of cobalt into the bloodstream. The syndrome in these patients was similar to those in beer drinkers from Quebec.
What is the pathophysiology of cobalt cardiomyopathy?
Cobalt has a variety of effects on the heart, both microscopically and biochemically.
Cobalt may have multiple calcium-mediated cardiac effects and may also interfere with the Krebs cycle and ATP generation by mitochondria. Histology may show modest changes with no inflammatory response on microscopy and ultrastructural changes, including vacuolar degeneration and swollen and distorted mitochondria with loss of cristae.
Remarkably, cardiac dysfunction does not correlate with serum cobalt levels. 2
How does cobalt cardiomyopathy present, and how do we diagnose it?
Diagnosis is made with a consistent exposure history and high index of suspicion. Patients present with anorexia and cachexia and complain of rapid onset and progression of symptoms of cardiomyopathy.
Labs may show polycythemia and thyroid dysfunction. Cobalt levels should be elevated, but the severity of the disease does not correlate well with levels.
Cardiac workup: EKG shows low voltage from infiltration and pericardial effusion. Echocardiogram shows systolic dysfunction and pericardial effusion. MRI shows diffuse infiltrative pathology. Native heart pathology is often diagnostic. 2
How is cobalt cardiomyopathy managed?
Medical management of heart failure, including guideline directed medical therapy (GDMT), inotropic support, and mechanical circulatory support, implantable device or transplant where appropriate.
Oral chelating agents should be used.
The mainstay of management is the removal of the prosthesis or source of exposure. 2
What is the prognosis of Cobalt Cardiomyopathy?
In the beer-drinker population, the prognosis was bad. Patients in that population had rapid clinical progression leading to cyanosis, marked elevation of cardiac and hepatic enzymes, lactic acidosis, and shock, and a high mortality rate (of 10%–40%), which was proportional to the daily intake of beer. 2
Some patients may recover function after removal of the cobalt source and normalization of the levels. However, some patients, like our patient, continue to have deterioration of function despite lower Cobalt levels requiring mechanical support and heart transplant.
Infographic made by the team (Made with BioRender – license included)
