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A 25-year-old woman presented at 12 weeks gestation, with symptoms and laboratory investigations consistent with pheochromocytoma. Imaging modalities available during pregnancy were limited and MRI scan of the abdomen and the neck failed to localise the tumour. Postpartum imaging, including 131-metaiodobenzylguanidine and octreotide scans, cardiac CT, cardiac MRI and cardiac catheterisation, allowed accurate localisation of the tumour and helped plan for successful surgical removal.
Cardiac pheochromocytoma is a rare condition, and to our knowledge this is the first time it has been reported in pregnancy. Although imaging modalities available during pregnancy are limited, making the diagnosis difficult, a possible cardiac location needs to be considered. In contrast, the imaging modalities available post-partum provide a wealth of information allowing accurate tumour localisation and surgical planning.
A 25-year-old woman, G2P1, presented at 12 weeks gestation after experiencing episodic bouts of diaphoresis, palpitations, headaches and light headedness. Her systolic blood pressure was 190/145 mm Hg, and her heart rate was 226 bpm. Her past medical history and family history were unremarkable. A 24-h urine collection, collected at 14 weeks gestation, demonstrated a dramatically elevated excretion of norepinephrine at 14 969 nmol/24 h (normal non-pregnant range <500) and normetanephrine at 18.4 μmol/24 h (normal non-pregnant range <3.3). A presumptive diagnosis of pheochromocytoma was made and medical therapy with α-blockade (phenoxybenzamine) and β-blockade (metoprolol) was initiated.
An MRI scan of the abdomen and neck failed to localise a tumour. A caesarean section was performed at 34 weeks gestation without complications, and a healthy daughter, weighing 2166 g, was born.
Postpartum, further imaging studies were able to be performed to localise the source of the excessive catecholamine secretion. An octreotide and a 131-metaiodobenzylguanidine (MIBG) scan both showed uptake in the right lower retrosternal area. A dedicated cardiac MRI (figure 1) and cardiac CT (figure 2) showed a highly vascular tumour located in the right atrioventricular (AV) groove in the RCA (right coronary artery) territory, closely attached to the myocardium; this was confirmed on cardiac catheterisation (figure 3).
The patient was taken to the operating room and intraoperatively; each time the tumour was touched (even delicately) the heart went into supraventricular tachycardia. These episodes responded to intravenous esmolol boluses. The tumour was found to be in the layer between the epicardium and the myocardium, without myocardial invasion. It extended from the right AV groove at the tricuspid valve to one-third of the way down the anterior wall of the right ventricle and did not involve the tricuspid valve. The entire tumour was resected successfully, with reconstruction of the right atrial and ventricular walls with bovine pericardium as well as tricuspid valve repair and CABG of the RCA (native RCA was sacrificed during tumour removal). Pathological examination confirmed a paraganglioma.
Postsurgery, despite discontinuation of α- and β-blockade, the patient was bradycardic and hypotensive requiring epinephrine, vasopressin and norepinephrine infusions. The epinephrine and vasopressin infusions were weaned by postoperative day (POD) #1, and the patient was off all vasopressors by POD#2. She could not be extubated until POD#2, due to excessive lethargy and weakness. Currently, 18 months postsurgery, she is well; her spells have completely resolved with normalisation of heart rate, blood pressure and urinary excretion of norepinephrine and normetanephrine.
Catecholamine-secreting tumours arise from chromaffin cells of the adrenal medulla (pheochromocytoma) or the autonomic nervous system (extra-adrenal pheochromocytomas, also called extra-adrenal catecholamine-secreting paragangliomas) and are rare with an annual incidence of 2–8 cases per million.1 Of these, only 2% are mediastinal paragangliomas.2 Brown et al3 described a case series of 12 patients with mediastinal paragangliomas; in all patients the tumour was adjacent to the heart or great vessels. Medical pretreatment, often with α- and β-blockade, is recommended to prevent a hypertensive crisis. The majority of cardiac pheochromocytomas are successfully treated with surgical resection. However, in cases where these vascular tumours are significantly invading the myocardium, there can be significant mortality and inability to completely excise the tumour; therefore, it has been suggested that cardiac transplantation could be an alternative option.4
To our knowledge, cardiac pheochromocytoma presenting during pregnancy has not been previously described.
Competing interests None.
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