Pheochromocytoma presenting as takotsubo cardiomyopathy: A nearly missed diagnosis in the absence of hypertension.
Simon R, Hejab A, and Lahiri S. Pheochromocytoma presenting as takotsubo cardiomyopathy: A nearly missed diagnosis in the absence of hypertension. Endocrine Reviews 2017; 38(3).
Pheochromocytoma (PCC) is a rare neuroendocrine tumor with a heterogeneous presentation. Headaches, palpitations and diaphoresis occur in 60-80% of cases, yet 8% are asymptomatic (1). Hypertension is found in 80-90%, although 13% are normotensive (1). The frequency of cardiovascular complications in PCC is not well studied, but reports of Takotsubo cardiomyopathy (TC) have been increasing (2). We report a case of a normotensive female presenting with TC and cardiogenic shock who was diagnosed with PCC. The diagnosis was considered only after the incidental discovery of an adrenal tumor. A 66-year-old female presented to the emergency department with acute onset chest pain, vomiting and back pain. She was hypotensive and tachycardic. Electrocardiogram showed sinus tachycardia and new anterior ST segment elevations. Laboratory evaluation revealed markedly elevated troponin. She also had acute kidney injury, acute liver injury with elevated transaminases >1000 IU/L (reference/L) and elevated lactate. She underwent emergent cardiac catheterization showing normal coronary arteries. Echocardiogram revealed reduced ejection fraction (EF) of 13% with severe hypokinesis of the anterior, lateral and inferior wall. Takotsubo cardiomyopathy was diagnosed although she did not report any acute physical or emotional stress. Inotropic support and afterload reduction led to clinical improvement. Cardiac imaging 6 days later demonstrated dramatic improvement of EF to 64%. An abdominal ultrasound performed on presentation to evaluate the abnormal liver function revealed a right upper quadrant mass of uncertain origin. This prompted abdominal computed tomography which showed an 8.5 x 8 x 7.5 cm heterogeneous adrenal mass. On further questioning, the patient reported a 3-year history of debilitating episodes of substernal pressure associated with belching, vomiting, and palpitations. Her symptoms had been diagnosed as gastroesophageal reflux disease. PCC had not been considered since she was always normotensive. Hormonal testing to evaluate this mass revealed elevated total plasma free metanephrines 20,878 pg/ml (/ml) with normetanephrine 17,279 pg/ml and metanephrines 3599 pg/ml. Catecholamine excess from PCC was considered to be the cause of her TC. Doxazosin was titrated over 3 weeks for adequate alpha blockade and propranolol was added prior to surgery to control reflex tachycardia. She underwent a successful open adrenalectomy. Pathology confirmed PCC. Pheochromocytoma is a rare disease with variable presentation. Takotsubo cardiomyopathy is an increasingly recognized, yet still uncommon, presentation of PCC. In our patient, the diagnosis of PCC was entertained only after an adrenal mass was incidentally found on imaging. We suggest evaluation for PCC in patients with TC even in the absence of hypertension, as a missed diagnosis can have fatal consequences.