Cardiovascular Manifestations and Complications of Pheochromocytomas and Paragangliomas

Abstract

Pheochromocytomas and paragangliomas (PPGLs) are rare neuro-endocrine tumors. The catecholamine surge causes paroxysmal or chronic secondary hypertension. PPGLs may present as hypertensive- or PPGL-crisis with severe life-threatening cardiac and cerebrovascular complications. PPGLs-induced cardiac manifestations have been reported with diagnoses as PPGLs-induced electrocardiogram (ECG) changes “mimicking acute myocardial infarction”, arrhythmias, myocarditis, acute coronary syndrome, dilated cardiomyopathy, and lately as takotsubo syndrome. Critical analysis of these reports reveals that most of these cardiac manifestations have certain features in common. They have a dramatic clinical presentation and are reversible if the disease is treated with appropriate medical therapy and surgical resection of the PPGL tumor. They may have the same repolarization ECG changes irrespective of the clinical cardiac diagnosis, usually associated with mild to moderate elevations of myocardial biomarkers as troponins and normal coronary arteries. The histopathological findings are usually focal or multifocal in the form hypercontracted sarcomeres and contraction band necrosis (myofibrillar degeneration) with subsequent secondary mononuclear cell infiltration. Evidences argue the PPGL caused surge of catecholamines triggers hyperactivation of the sympathetic nervous system with cardiac sympathetic nerve terminal disruption with norepinephrine spillover causing the cardiac complications. A comprehensive review of various reported cardiovascular manifestations and complications of PPGLs are presented.

Pheochromocytoma as a cause of repeated acute myocardial infarctions, heart failure, and transient erythrocytosis: A case report and review of the literature

“…The coronary angiogram showed nonobstructed coronary arteries. We noted that most of such patients had few significant coronary atherosclerosis in past reports[ 8 - 10 ]. Most reports suggested that cardiomyopathy, severe coronary vasospasm, myocarditis, and tachycardia caused by excessive release of catecholamines result in elevated cardiac troponin and reduced left ventricular systolic function[ 11 , 12 ].…”

Case Report: Pheochromocytoma in a 59-Year-Old Woman Presenting With Hypotension

“…Norepinephrine secreted by pheochromocytoma can cause structural and functional remodeling of the heart, such as left ventricular hypertrophy. Catecholamines, especially norepinephrine, can cause myocardial damage by increasing the oxygen consumption and apoptosis of cardiomyocytes and can further lead to left ventricular systolic dysfunction and dilated cardiomyopathy ( 14 , 15 ). Some factors can lead to an imbalance of the oxygen supply and demand, such as cardiotoxicity of catecholamines, increased muscle mass and coronary artery spasm, causing myocardial ischemic necrosis ( 16 , 17 ).…”

Metastatic Pheochromocytomas and Abdominal Paragangliomas

“…Other symptoms include chest pain, psychiatric symptoms, hyperglycemia, constipation, and syncope. Uncommon presenting symptoms include Takotsubo syndrome ( 22-24 ), other life-threating cardiovascular events ( 25 ), and preeclampsia ( 26 ).…”

“…However, patients using phenoxybenzamine less frequently had intraoperative systolic blood pressure above the target range and hemodynamic instability. The intravenous alpha-blocker phentolamine is preferred in emergency situations, such as PPGL-crisis, due to its quick onset ( 25 ). Calcium channel blockers (nifedipine or amlodipine) normally are used as an addition to alpha adrenergic receptor blocker if further blood pressure control is required or occasionally for patients not tolerating alpha-blockers ( 76 , 79 ).…”

“…In contrast, beta-blockers are used to control tachycardia. However, it is essential that alpha-blockers are commenced first to avoid potential PPGL-crisis since beta-blockers alone may aggravate epinephrine-induced vasoconstriction by blocking its vasodilator component, ie, unopposed alpha-receptor stimulation ( 25 , 79 ). Propranolol, metoprolol, or atenolol are commonly used beta-blockers.…”