A Series of Two Patients With Cardiac Paragangliomas

Abstract

The objective of this report is to present 2 cases of cardiac paragangliomas (PGLs), and to outline the presentation, management, and associated genetic mutations. Case 1, a 38-year-old female, presented with a 12-month history of paroxysmal palpitations, headaches, and weight loss. Her investigations included plasma free metanephrines and urinary metanephrines, 68-gallium DOTATATE positron emission tomography/computed tomography, and cardiac imaging. Case 2, a 28-year-old male, presented with a hypertensive crisis and abdominal pain on a background of hypertension. Given his abdominal pain, he was investigated with an abdominal computed tomography (CT) scan, followed by plasma free meta-nephrines and urinary metanephrines, echocardiogram, and 123-iodine meta-iodobenzylguanidine single-photon emission CT. Case 1 had an elevated plasma normetadrenaline of 6,750 pmol/L (reference range is <900 pmol/L) and 3-methoxytyramine of 1,845 pmol/L (reference range is <110 pmol/L). 68-gallium DOTATATE positron emission tomography/computed tomography showed an avid cardiac lesion. The lesion was resected, and histopathology confirmed PGL. Genetic studies revealed an SDHC gene mutation. For case 2, abdominal CT revealed a para-spinal mass. Workup for this lesion revealed elevated normetadrenaline of 56,000 pmol/L (reference range is <900 pmol/L). An echocardiogram, arranged for investigation of hypertension, showed an additional cardiac mass. A 123-iodine meta-iodobenzylguanidine single-photon emission CT scan confirmed that both masses were functioning. The lesions were successfully excised. He was found to have an SDHB gene mutation. Both patients had long-standing symptoms secondary to catecholamine excess, thus it is important to promptly screen patients with unexplained hypertension or paroxysmal symptoms of palpitations, headaches, and diaphoresis with plasma free metanephrines or urinary metanephrines. All patients with PGLs should be offered genetic testing due to the high incidence of genetic mutations.