The clinical manifestations of polyarteritis major can be divided into two phases: the initial active phase and the later vascular occlusion phase. I. Active phase: About 3/4 of patients develop the disease in adolescence. The onset of disease is mostly slow, with systemic symptoms such as fever, palpitations, general malaise, loss of appetite, weight loss, night sweats, joint pain and fatigue. There may be limited pain and tenderness at the artery of the lesion. Symptoms may subside on their own during the active phase, and signs and symptoms of occlusion of large arteries and branches may appear after a long insidious phase. Vascular occlusion phase: Vascular murmurs and tremors may be present at the narrowed lesion, and the distal arterial pulses may be weakened or absent, and the blood pressure may be reduced or undetectable. The lesions mainly involve the aortic arch and head wall vessels. When the carotid artery and vertebral artery stenosis is blocked, there can be different degrees of cerebral ischemia, manifested as dizziness, headache, vertigo, visual disturbance, etc. In severe cases, syncope may occur. Carotid artery pulsations are weakened or absent, and vascular murmurs can be heard, rarely accompanied by tremors. Anemia such as fundus retinaculum. When the subclavian artery is involved, weakness, numbness and coldness of the affected limb may occur, and intermittent limb pain after activity. The pulsation of the radial artery on the affected side is weakened or disappears, and the blood pressure is reduced or undetectable, which is known as pulselessness. 2, thoracoabdominal aorta type: About 17% of the lesions are mainly located in the thoracoabdominal aorta and its branches, especially the renal artery. Due to ischemia of the lower limbs, symptoms such as weakness, numbness, coldness and intermittent claudication may occur. The pulses in the lower extremities are weakened or absent and the blood pressure is reduced, while the blood pressure in the upper extremities may be elevated. Some patients may also have intestinal ischemic colic and intestinal dysfunction. In combination with renal artery stenosis, hypertension is the main manifestation. On physical examination, vascular murmurs can be heard in the abdomen and kidney area. The lesion involves the opening of the renal artery or its proximal segment of the abdominal aorta, presenting renal hypertension. The blood pressure of the lower extremities may be reduced in those with abdominal aortic involvement. 4. Extensive (mixed) type: About 38-41.5% of the cases have the characteristics of the above three types, with multiple lesions and mostly severe disease. The renal artery is more commonly involved, so there is often significant hypertension. Other symptoms and signs vary depending on the involved vessels. All four types can be combined with pulmonary artery involvement, and pulmonary hypertension may develop in advanced stages. In addition, coronary artery openings and proximal arteries can also be involved, and angina pectoris or even myocardial infarction can occur. The lesion is located in the aortic arch and its branches. Occlusion at the carotid artery may cause dizziness, visual disturbance, syncope, hemiparesis; vascular murmur can be heard in the neck, carotid pulsation disappears, and retinal anemia can be seen in the fundus of the eyes. If the subclavian artery is occluded, numbness, weakness and coldness of the affected limbs may occur, and the limb pain after activity; the radial artery pulsation is weakened or disappears, blood pressure is reduced or not measured, and a vascular murmur can be heard in the subclavian artery. If the vertebral artery is involved, there may be episodes of vertigo. 2.Type II: The lesion involves the abdominal aorta and its branches. If the lesion involves the abdominal aorta, there may be intestinal dysfunction or intestinal infarction. If the common iliac artery is involved, there may be numbness and coldness of the lower limbs, weakness, intermittent claudication and decreased arterial pressure in the lower limbs, weakened or absent pulse, and a vascular murmur may be heard in the iliac artery. If the renal artery is involved, renal hypertension may result, and vascular murmurs may be heard in the renal area or around the umbilicus. 3.Type III: The scope of lesion includes type I and type II. The clinical manifestations of the above two types may be present simultaneously. Type IV: Involvement of pulmonary artery, shortness of breath, palpitations, systolic murmur in pulmonary valve area and pulmonary hypertension signs. In recent years, it has been found that the lesion can involve the coronary artery opening and cause angina pectoris or myocardial infarction.