Pheochromocytoma is a tumor originating in the adrenal medulla, sympathetic ganglia, parasympathetic ganglia, or other sites of chromophobic tissue. It can intermittently or continuously secrete excessive catecholamines (epinephrine, norepinephrine, etc.), causing persistent or paroxysmal hypertension and multiple organ dysfunction and metabolic disorders, which is a secondary hypertension. The prevalence is about 0.1%-1% of hypertensive patients, and the prevalence is about the same in both sexes. Benign tumors account for about 80-90% of cases, while malignant ones account for 10-20%. The tumor is about 12-16 cm in diameter and weighs from a few grams to 3 kg, varying in size, usually about 100 grams. Patients with pheochromocytoma have special clinical manifestations, which are caused by increased secretion of epinephrine and norepinephrine in different proportions, either paroxysmally or continuously: 1. Hypertension: the main symptom, mostly persistent or paroxysmally elevated blood pressure, accompanied by episodes of headache, sweating, palpitations, pale face and skin, tremors of limbs and head, coldness of hands and feet, numbness, blurred vision, dilated pupils, anxiety The symptoms include: anxiety, fear, feeling of imminent death, nausea, vomiting, etc. 2, cardiac manifestations: large amounts of catecholamines can cause arrhythmias such as premature beats, paroxysmal tachycardia, and even ventricular fibrillation. Some patients may have myocardial degenerative lesions, necrosis and inflammatory changes. Heart failure can also occur due to myocardial damage. Myocardial hypertrophy, heart enlargement, and heart failure may also occur due to persistent hypertension. Patients may have chest tightness, shortness of breath, dyspnea, etc. 3, increased basal metabolism, disorders of glucose metabolism (hyperglycemia, glycosuria, hypoglycemia), disorders of lipid metabolism and electrolyte metabolism (hypokalemia), etc. 4, may occur hypotension, shock or alternating performance of hypertension and hypotension. 5.Other: such as constipation, intestinal necrosis, bleeding or perforation, abdominal mass, renal hypofunction, etc. 6.Often triggered by mental stimulation, strenuous exercise, position change and squeezing the tumor. Generally, the attack lasts for several seconds, minutes or even 1-2 hours, or up to 16-24 hours in long cases. In the early stage, the attack occurs once every 2-3 months, but after 2-3 years, the attack becomes more and more frequent, and the more it occurs, the longer it lasts and the more it worsens. Those with persistent elevated blood pressure resemble hypertensive disease. Those with rapid progression are more like acute hypertension.