Role of integrated imaging in the diagnosis of an atypical and unresectable cardiac paraganglioma: a case report.

Background: Paragangliomas (PGLs) are rare neuroendocrine tumours that originate from extra-adrenal location. Cardiac PGLs can cause severe hypertension, palpitations, and lethal tachyarrhythmias. Diagnosis is based on measurement of plasma or urine metanephrines combined with conventional and nuclear imaging. Effective treatment is represented by surgical resection. We report a case of a 19-year-old patient with recurrent acute pericarditis; integrated imaging detected a large cardiac mass suggestive for PGL.

Case Summary: A 19-year-old male suffered pleuritic chest pain and fever for 4 days; electrocardiogram showed inferior ST elevation and transthoracic echocardiography a 2.2 cm pericardial effusion; these findings led to diagnose acute pericarditis. After a relapse of pericarditis, cardiac magnetic resonance and cardiac computed tomography (CCT) were performed, revealing a cardiac mass with radiological features of PGL. Blood and urine tests detected elevated levels of 3-methoxytyramine and chromogranin A. Gallium-68 positron emission tomography confirmed high metabolic activity of the mass. A negative 123-I-MIBG scintigraphy ruled out the possibility of radiometabolic treatment. A second CCT excluded the chance of surgical resection, due to intra-lesional course of the left anterior descending coronary artery. The young patient was referred to a different centre to achieve reduction of the mass, in order to potentially resect it afterwards.

Discussion: Cardiac PGLs are rare tumours with significant morbidity related to norepinephrine secretion. In this case, without typical clinical manifestations and with no chance of surgical resection, integrated imaging played a central role in the differential diagnosis between PGL and other cardiac masses, providing both static and dynamic characterization.