Clinical Pearls & Morning Reports
Published December 28, 2022
Paraganglioma and hemangiomas are rare as primary cardiac tumors, with each occurring in autopsy series at frequencies of 0 to 3.5%. Read the NEJM Case Records of the Massachusetts General Hospital here.
Q: Are coronary artery anomalies common?
A: In athletes, coronary-artery anomalies may manifest as syncope, presyncope, or at times, angina. Acute angulation of an aberrant coronary origin, dynamic compression by adjacent structures, and presumed obstructive ischemia are some proposed mechanisms of angina and sudden cardiac death that occur in the context of exercise. The precise prevalence of coronary-artery anomalies is unknown but is estimated to be approximately 1% or less in the general population. In a large autopsy study involving military recruits, 1 in 3 cases of sudden death that occurred in this athletic population were found to be caused by coronary-artery anomalies. In this study, most cases of sudden death were associated with the left coronary artery arising from the right sinus of Valsalva and then coursing between the pulmonary artery and the aorta.
Q: Is a newly discovered tumor of the heart more likely to be a primary or a metastatic lesion?
A: Tumors of the heart are rare, and when they occur, they are most likely to be metastatic disease that originated outside the heart. Primary tumors of the heart are exceedingly rare, with prevalence estimates in autopsy studies ranging from 0.001% to 0.3%. Most primary cardiac tumors are benign, and the most common type is cardiac myxoma, which often arises from the left atrium. Other benign cardiac tumors include fibroelastoma, mesothelial cyst, and teratoma. The few malignant primary cardiac tumors consist of lymphoma and various types of sarcoma, including angiosarcoma and leiomyosarcoma.
A: In a patient with a suspected cardiac sarcoma, the approach would be a confirmatory biopsy and the administration of adjuvant chemotherapy and radiation therapy after surgery. In contrast, if a patient had a suspected paraganglioma, the approach would be different, because biopsy of this hypervascularized and potentially secretory structure is relatively contraindicated. For paraganglioma, the approach involves preoperative embolization, pharmacologic alpha-blockade, and aggressive en bloc resection.
A: Given that up to 40% of patients with paraganglioma have a familial syndrome, genetic testing is recommended for all affected patients to determine the approach to monitoring. If the genetic testing is positive, the patient would undergo long-term screening tailored to the specific familial syndrome. For patients who have a germline mutation in the gene encoding succinate dehydrogenase subunit C, (associated with familial paraganglioma syndrome 3), imaging of the site of the original tumor should be performed on a yearly basis to rule out any evidence of local recurrence (if the original tumor has been removed) or growth (if the original tumor has not been removed). Imaging of other parts of the body that did not contain tumor at the time of initial diagnosis should be done every 2 to 3 years. Finally, a dedicated functional imaging study, most commonly positron-emission tomography (PET) and CT, should be done every 5 years. Recent data suggest that the most effective technique (fluorodeoxyglucose PET vs. dotatate PET) may vary, depending on the specific familial syndrome.