Cardiac pheochromocytoma originating in the interatrial septum

Transthoracic echocardiographic features of cardiac pheochromocytoma: a single-institution experience

BACKGROUND

Cardiac pheochromocytoma is extremely rare. Previous papers usually are reports of a single case. Transthoracic echocardiography (TTE) offers a useful option, but the features of cardiac pheochromocytoma on TTE have not been favorably reported. In this study, the findings of cardiac pheochromocytoma on TTE in nine cases were presented.

METHODS

TTE images (especially two-dimensional ultrasound) of nine patients with cardiac pheochromocytomas were analyzed retrospectively and compared with the findings from surgery.

RESULTS

Among the nine patients with cardiac pheochromocytomas identified in Peking Union Medical College Hospital (PUMCH) clinical and echocardiographic database, TTE identified one cardiac tumor in seven cases (77.8%), two cardiac tumors in one case (11.1%), and a false-negative result in another (11.1%). Cardiac pheochromocytomas were usually located on the base of the heart, near the origin of great arteries. The tumors were usually round or ovoid, ranging from 1.4 cm to 7.7 cm in diameter, with homogeneous and moderate echoes and low activity. They could press or invade surrounding cardiac structures and influence hemodynamics. In this study the majority of cardiac pheochromocytoma seemed marginated and appeared to be encapsulated on TTE. Apical four-chamber view and parasternal short-axis view of the aortic valve were most effective in identifying cardiac pheochromocytomas. The findings on TTE were similar to those from surgical procedures.

CONCLUSION

Cardiac pheochromocytomas presented characteristic TTE appearances in aspect of location, size, texture, and shape of tumors. Understanding of these characteristics on TTE can help correctly recognize this extremely rare disease.

A primary right atrium paraganglioma in a 15-year-old patient

Thoracic pheochromocytomas account for less than 2% of reported cases, while primary cardiac paragangliomas are even rare. The following case illustrates a 15-year-old patient with primary right atrium paraganglioma. This patient was referred for paroxysmal hypertension and excessive perspiration. Pheochromocytoma was suspected and then confirmed by very high serum nor-metanephrine which increased more than 30-fold above the upper limit of normal. 131I-metaiodobenzylguanidine (MIBG) scintigraphy showed high uptake only in the middle mediastinum, but not in the adrenal glands or elsewhere. Both contrast CT and gated MRI of the chest disclosed a 5.0 x 4.0 cm2 mass in the right atrium. Coronary angiography demonstrated the mass with feeding vessels from the right coronary artery. When the patient's blood pressure was well controlled with doxazosin and metoprolol, surgery was then performed. A 6.0 x 4.9 x 4.0 cm3 round solid right atrium paraganglioma weighing 41.7 g was resected. The second day after surgery, serum nor-metanephrine and urinary noradrenaline levels dropped rapidly to normal range, and the patient was free of clinical symptoms with normal BP. Postoperative cardiac function, as measured by echocardiogram, was normal. Although cardiac paraganglioma may be difficult to resect, it can be cured.

[Right atrial pheochromocytoma]

Pheochromocytoma is a catecholamine-producing tumor and a rare cause of hypertension. Most cases are intra-adrenal and intrapericardial pheochromocytomas are extremely uncommon. We report the case of a 46-year-old woman with a 1-year history of hypertension, in which a right atrial pheochromocytoma was detected after a hypertensive crisis. 131I-metaiodobenzylguanidine scintigraphy and magnetic resonance imaging established the diagnosis. The tumor was successfully resected using cardiopulmonary bypass and the right atrium was reconstructed using bovine pericardium.

Cardiac phaeochromocytoma presenting with severe hypertension and chest pain

Cardiac phaeochromocytoma is a rare cause of endocrine hypertension. We report a case of a 25-year-old woman, who presented with severe hypertension and intermittent chest pain. The patient denied typical phaeochromocytoma spells of palpitation, headache, and diaphoresis. The 24-hr urinary excretion of norepinephrine was increased sevenfold above the upper limit of normal; however, the excretion of total metanephrines, epinephrine, and dopamine were normal. Computed tomography (CT) scan of the abdomen was normal. An 131I-labelled metaiodobenzylguanidine (MIBG) scan was falsely negative while the patient was taking labetalol. The cardiac phaeochromocytoma was localized with indium-111-pentetreotide scintigraphy and chest magnetic resonance imaging scan. Repeat 123I-MIBG scintigraphy was positive after discontinuing labetalol. The cardiac phaeochromocytoma was located in the right atrial groove, adjacent to the tricuspid valve, and contained multiple feeder arteries from the right coronary artery. After treatment with volume expansion, alpha-methyl-p-tyrosine, and alpha- and beta-adrenergic blockade, surgical resection was performed. While under cardiopulmonary bypass, coronary bypass grafting and tricuspid annuloplasty were performed to facilitate the complete surgical resection of the 4.5-cm tumour. The surgical course was uncomplicated, with complete cure of hypertension and normalization of catecholamine excretion. Post-operative cardiac function, as measured by echocardiogram, was normal. Although cardiac phaeochromocytoma may be highly vascular, invasive and difficult to resect, it can be cured.

Cardiac pheochromocytoma

Primary pheochromocytomas of the heart are extremely uncommon. In this report, we present the case of a patient with primary cardiac pheochromocytoma arising from the interatrial septum. Metaiodobenzylguanidine-scintigraphy was negative and diagnosis was confirmed by a positive octreotide scintiscan. The tumor was removed successfully using cardiopulmonary bypass.

CT and MR imaging of benign primary cardiac neoplasms with echocardiographic correlation

Benign primary cardiac neoplasms are rare but may cause significant morbidity and mortality. However, they are usually treatable and can often be diagnosed with echocardiography, computed tomography (CT), or magnetic resonance (MR) imaging. Myxomas typically arise from the interatrial septum from a narrow base of attachment. Fibroelastomas are easily detected at echocardiography as small, mobile masses attached to valves by a short pedicle. Cardiac fibromas manifest as a large, noncontractile, solid mass in a ventricular wall at echocardiography and as a homogeneous mass with soft-tissue attenuation at CT. They are usually homogeneous and hypointense on T2-weighted MR images and isointense relative to muscle on T1-weighted images. Paragangliomas usually appear as large, echogenic left atrial masses at echocardiography and as circumscribed, heterogeneous masses with low attenuation at CT. These tumors are usually markedly hyperintense on T2-weighted MR images and iso- or hypointense relative to myocardium on T1-weighted images. Cardiac lipomas manifest at CT as homogeneous, low-attenuation masses in a cardiac chamber or in the pericardial space and demonstrate homogeneous increased signal intensity that decreases with fat-saturated sequences at T1-weighted MR imaging. Cardiac lymphangiomas manifest as cystic masses at echocardiography and typically demonstrate increased signal intensity at T1- and T2-weighted MR imaging. Familiarity with these imaging features and with the relative effectiveness of these modalities is essential for prompt diagnosis and effective treatment.

Surgical management of cardiac pheochromocytoma. Resection versus transplantation

OBJECTIVE

The authors review their experience and that of others who have reported cases in the literature on the surgical management of cardiac pheochromocytomas.

SUMMARY BACKGROUND DATA

Cardiac pheochromocytomas are rare cathecolamine-producing tumors that can be densely adherent to myocardium. Because resection can be associated with significant morbidity, we sought to determine the best mode of treatment for these difficult tumors.

METHOD

The authors reviewed the experience for management of cardiac pheochromocytomas in their two institutions and those reported in the literature. Follow-up was available for 21 of 26 patients up to 9 years after resection.

RESULTS

Twenty-five patients had reconstruction of the native heart; five (20%) died intraoperatively from hemorrhage, one (4%) died postoperatively from sepsis, three (12%) sustained myocardial infarction, one (4%) required a mitral valve replacement, and three (12%) had incomplete resections, two of whom subsequently developed metastatic disease and died. One patient, thought to be a high risk for resection, received an orthotopic heart transplantation.

CONCLUSIONS

Surgical resection of cardiac pheochromocytomas can be performed successfully. However, resection of lesions that aggressively invade adjacent myocardium is associated with significant mortality and inadequate control of the neoplasm. Cardiac transplantation should be available as an option before embarking on resection, and it should be performed if mandated by intraoperative findings.

Pheochromocytoma. Update on diagnosis, localization, and management

Pheochromocytoma, although rare, is associated with a high degree of morbidity and mortality if not recognized. A high degree of suspicion in patients with new-onset hypertension; hypertension with sudden worsening or development of diabetes mellitus; or a family history of MEN, neuroectodermal tumors, or simple pheochromocytoma should prompt biochemical confirmation with either 24-hour urine catecholamines (norepinephrine and epinephrine) or total MET (NMET plus MET). Following confirmation of the diagnosis, radiologic studies with CT and (if needed) MIBG are employed to localize the tumor. Surgical removal is the only definitive therapy. Medical management with alpha-blocking agents, to control symptoms and prevent a hypertensive crisis, is generally advocated for 2 weeks preoperatively and intraoperatively. Occasionally, beta-blockers, employed only after adequate alpha-blockade, are necessary to control tachycardia and tachyarrhythmias. High-dose MIBG and combination chemotherapy have been used adjunctively to treat malignant pheochromocytoma, although neither modality provides lasting satisfactory results. Normal urine assays performed 2 weeks postoperatively ensure the complete removal of all tumor. Additionally, lifelong follow-up (yearly initially) is necessary to detect any signs of benign recurrence or malignancy because these have been reported to occur as long as 41 years after the initial surgical resection. Biochemical evidence of excess catecholamine production usually precedes the clinical manifestations of catecholamine excess when these tumors recur.

Cardiac pheochromocytomas

Cardiac pheochromocytomas are rare. Thirty cases have been reported in the literature. We report the cases of 2 more patients in whom the diagnosis was established using coronary angiography and who underwent surgical resection using cardiopulmonary bypass. We also review the literature on the subject.