1.What is peripheral vascular disease? What is the incidence? Peripheral vascular disease is a generic term for peripheral vascular disease. They can be classified as arteriopathies and venous diseases according to the type of involved vessels; they can be classified as obstructive diseases and dilated diseases according to the type of lesions. They mainly include atherosclerotic occlusive disease, abdominal aortic aneurysm, thoracic aortic aneurysm, aortic coarctation, varicose veins, spermatic varicose veins, thrombophlebitis, vasculitis, Buga’s syndrome, Raynaud’s syndrome, etc. The most common and dangerous disease in clinical practice is atherosclerotic occlusive disease, with lesions mostly found in the lower limb arteries, carotid arteries, subclavian arteries, renal arteries, superior mesenteric arteries and other vessels. Approximately 70% of the population older than 60 years of age may have varying degrees of atherosclerosis-occlusive disease, with approximately 20% of patients requiring hospitalization. Varicose veins are the most common clinical peripheral vascular disease, with an overall incidence of about 10% in the population. Aortic coarctation, thoracic aortic aneurysm and abdominal aortic aneurysm are by far the most clinically dangerous peripheral vascular diseases, with the main risk being death due to vessel rupture. The incidence of aortic coarctation is about 50 to 100 per 100,000 people, the incidence of thoracic aortic aneurysm is about 200 to 400 per 100,000 people, and the incidence of abdominal aortic aneurysm is about 5% for those over 50 years old. 2.What are the causes of peripheral vascular disease? (1) The main causes of atherosclerosis-occlusive disease include: hypertension, hyperlipidemia, diabetes, hyperuric acid, homocysteinemia and smoking. (2) The main causes of varicose veins in the lower extremities include: genetic factors, prolonged standing, heavy physical labor and obesity. (3) The main causes of abdominal and thoracic aortic aneurysms include: atherosclerosis, hereditary diseases (Marfon syndrome, Edu syndrome), syphilis, trauma and infection. (4) The main causes of aortic coarctation include: hypertension, atherosclerosis, hereditary diseases (such as Mafang syndrome, Edu syndrome) and trauma, etc. 3.What are the symptoms of peripheral vascular disease? What are the hazards to human body? What are the high-risk groups? (1) Arteriosclerosis occlusive disease includes lower limb arteriosclerosis occlusive disease, carotid artery stenosis, subclavian artery stenosis, renal artery stenosis, etc. The typical symptoms of different stages of lower extremity atherosclerosis occlusive disease are: ① intermittent claudication: i.e., the lower extremity walking a certain distance due to muscle ischemia, metabolite accumulation produces soreness, and requires rest to relieve to continue walking; ② resting pain: after the ischemia is aggravated, the metabolism of the lower extremity cannot meet the resting state, producing persistent pain; ③ ulcer: ischemia continues to aggravate, tissue necrosis due to insufficient nutrition, other symptoms include cold sensation, weakness, numbness and wasting of the lower limbs. Lower extremity atherosclerosis occlusive disease can affect the quality of life of patients in mild cases and lead to limb necrosis and amputation in severe cases. Typical symptoms of carotid artery stenosis are black haze, TIA and stroke. The main risks to human body are causing stroke and affecting vision. Typical symptoms of subclavian artery stenosis are upper limb weakness, asymmetric blood pressure in the upper limbs, pulselessness in the upper limbs and vertigo after upper limb activity. The main danger is that it can lead to cerebellar ischemia and weakness and atrophy of the upper limbs. The main symptoms of renal artery stenosis are the development of uncontrollable hypertension and progressive rise in creatinine, and the main hazards are leading to kidney atrophy, renal failure and uncontrollable blood pressure. High-risk groups for atherosclerotic occlusive disease include long-term smokers, hypertensive, hyperlipidemic, diabetic patients and homocysteinemia. (2) Typical symptoms of varicose veins in the lower extremities include: early symptoms are earthworm-like bruising of the blood vessels in the legs, which can be without any discomfort. With the aggravation of the disease, swelling of the affected limbs, fatigue after activity, swelling and pain, increased and thickened bulging blood vessels may appear. Then some complications will gradually appear, such as: local hyperpigmentation, eczema, thrombophlebitis, subcutaneous fat sclerosis, and finally local rupture for a long time. When the symptoms of varicose veins in the lower extremities are mild, they mainly affect the aesthetics, but when they develop to a certain extent, they can significantly affect the quality of life and eventually lead to limb dysfunction. High-risk groups include people who stand for long periods of time, heavy workers, and people with a family history of varicose veins. (3) The typical symptoms of abdominal aortic aneurysm are: a pulsating and distending mass can be palpated in the abdomen, painful compression of the spine when the mass enlarges, obstructive symptoms when the mass compresses the surrounding organs, and ischemia of the arteries in the lower limbs when the thrombus in the aneurysm cavity is dislodged; significant abdominal pain and hypotension can occur when the aneurysm ruptures. The greatest danger of abdominal aortic aneurysm to human body is the rupture of the aneurysm leading to death. Abdominal aortic aneurysms are more likely to occur in people with long-term smoking, hypertension, constipation, and chronic bronchitis. (4) The onset of thoracic aortic aneurysm is slow: there may be no symptoms and signs in the early stage; chest pain may appear when the aneurysm gradually increases; various symptoms may appear when the aneurysm compresses the surrounding tissues; cough or difficulty in breathing and tracheobronchial deviation may appear when the aneurysm compresses the tracheobronchus; difficulty in swallowing may appear when the aneurysm compresses the esophagus; hoarseness may appear when the aneurysm compresses the recurrent laryngeal nerve; pulmonary stenosis or superior vena cava may appear when the adjacent blood vessels are compressed Venous syndrome, and cerebral ischemia can be caused by obstruction of the head and arm vessels. In addition to the symptoms caused by thoracic aortic aneurysm during its development, which affects the patient’s quality of life, the most important hazard is the rupture of the aneurysm leading to the patient’s death. High-risk groups are patients with hypertension, those with significant vascular atherosclerosis, patients with familial hereditary diseases (Marfon syndrome, Edu syndrome), and patients with syphilis are also prone to aneurysmal transformation. (5) The typical symptoms of aortic coarctation are: sudden onset of chest and back pain, accompanied by significant increase in blood pressure in most patients; black haze and hemiparesis when the coarctation involves the blood vessels supplying the brain; significant abdominal pain when the superior mesenteric artery is involved; hemiparesis when the long segment of the spinal cord artery is involved; cold pain in the lower limbs and unsteadiness when the lower limb vessels are involved. The risk of entrapment is extremely high and can lead to disability in mild cases and sudden death in severe cases. High-risk groups include patients with familial genetic diseases (Marfon syndrome, Edu syndrome), hypertension and atherosclerosis, and trauma also leads to the occurrence of entrapment. 4.How is peripheral vascular disease diagnosed? How to avoid missed diagnosis and misdiagnosis? What are the early symptoms of the disease that remind us to go to the hospital in time? The diagnosis of peripheral vascular disease mainly relies on typical symptoms, physical examination and imaging examinations. Knowing more about peripheral vascular disease can help avoid underdiagnosis and misdiagnosis. For example, the most common type of peripheral vascular disease is lower extremity atherosclerosis occlusive disease, and patients should seek medical attention if they experience chills in the lower extremities and have limited walking distance. For lower extremity atherosclerotic occlusive disease, primary screening can be performed by ultrasound, imaging diagnosis by lower extremity CTA or MRA, and non-invasive vascular testing (PVL) for ankle-brachial index (ABI) can help quantify the degree of lower extremity ischemia. For carotid artery stenosis, carotid ultrasound screening should be routinely performed in the older age group >60 years. If stenosis is determined to be severe, a definitive diagnosis should be made by CTA or MRA. For subclavian artery stenosis, the typical symptoms are asymmetric blood pressure in both upper extremities or unilateral upper extremity pulselessness. Once these symptoms appear, one should go to the hospital for diagnosis, which mainly relies on imaging examinations such as ultrasound, CTA and MRA. For renal artery stenosis, the initial screening can be performed by color ultrasound, and the diagnosis relies on imaging examinations such as CTA and MRA. The diagnosis of abdominal aortic aneurysm, thoracic aortic aneurysm and coarctation mainly relies on imaging examinations such as CTA and MRA. 5.What are the current common clinical treatments for peripheral vascular disease? The treatment of peripheral vascular disease includes non-surgical treatment, traditional surgical treatment and minimally invasive treatment. Take lower extremity atherosclerosis occlusive disease as an example, the specific treatment is as follows: (1) correcting bad habits, such as quitting smoking and eating a light diet; (2) physical exercise, insisting on walking each time until the lower extremity becomes sore, and multiple exercises can prolong the distance between limps; (3) medication, oral antiplatelet drugs such as aspirin and clopidogrel, oral statins such as Lipitor can help lower blood lipids and stabilize plaque, oral (4) surgical treatment including lower limb arterial endarterectomy, artificial vascular bypass, autologous saphenous vein bypass, etc.; (5) minimally invasive treatment including lower limb balloon dilatation angioplasty (PTA), stent implantation (stent), etc. In recent years, for suitable patients, stem cell therapy helps to improve the symptoms. 6.How to prevent peripheral vascular disease as a general population? Take lower extremity atherosclerosis occlusive disease as an example, as an ordinary person, the means of prevention include: (1) weight control, smoking and alcohol cessation, light diet; (2) control of blood pressure, blood sugar, uric acid, cysteine; (3) adhere to physical exercise .