Arteriovenous malformations (AVMs) happen when a group of blood vessels in your body forms incorrectly. 在这些畸形中, arteries and veins are unusually tangled and form direct connections, 绕过正常组织. This usually happens during development before birth or shortly after.

Most people with AVMs have no initial symptoms or problems. Instead, the problem is discovered when health care providers treat another unrelated health concern. Sometimes the rupture of one of the blood vessels in an AVM will bring the issue to medical attention. Sometimes AVMs are only found after death, during an autopsy.

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©Eleanor Bailey

关于avm的事实

Most people with AVMs will never have any problems. If symptoms have not appeared by the time a person is 50, they may never appear. Women sometimes have symptoms as a result of the burden that pregnancy places on the blood vessels. Nearly 12 percent of people with AVMs do have some symptoms, however.

没有人知道为什么会形成avm. Some experts believe that the risk of developing AVMs could be genetic. 动静脉畸形可以在身体的任何部位形成. Those that form in the brain or close to the spinal cord, 称为神经性动静脉畸形, 最有可能产生长期影响吗.

The biggest concern related to AVMs is that they will cause uncontrolled bleeding, or hemorrhage. Fewer than 4 percent of AVMs hemorrhage, but those that do can have severe, even fatal, effects. Death as a direct result of an AVM happens in about 1 percent of people with AVMs.

Sometimes AVMs can reduce the amount of oxygen getting to the brain and spinal cord (this is sometimes called a "steal" effect, as if the blood were being "stolen" from where it should be flowing). AVMs can sometimes put pressure on surrounding tissues. Steal can also occur elsewhere in the body, such as in the hands or feet, but may not be as apparent.

An AVM occurs when arteries and veins aren't formed correctly in an area of the body. Normally arteries take blood from the heart to the body. Blood with fresh oxygen and nutrients is brought through the arteries into very tiny vessels called capillaries. Through these tiny vessels, blood travels into the body's tissues. Blood then leaves the tissues through the capillaries and empties into veins, 让血液回到心脏. Capillaries are tiny vessels that help the blood to slow down. This allows the blood to deliver oxygen and nutrients into tissues.

在AVM中, 没有毛细血管, 所以血液不会减慢, and it does not get to deliver oxygen and nutrients to the body's tissues. Instead, blood that is flowing very fast (high flow) goes directly from an artery to a vein. 很少, 如果有很多血流通过动静脉畸形, it can cause the heart to work too hard to keep up, 导致心力衰竭.

虽然出生时就存在, an AVM may be found soon after birth or much later in life, 取决于它的大小和位置. AVMs can become apparent after an accident or as a child grows into an adult (during puberty). 随着推荐十大正规网赌平台身体的成长，AVM也在成长.

avm会随着时间的推移而增长和变化. AVMs are often organized using a scale called the Schöbinger staging system. 并不是所有的AVMS都会经过每一个阶段.

• 第一阶段(静止):AVM处于“安静”状态." The skin on top of the AVM may be warm and pink or red.
• 第二阶段(扩张):AVM变大. 在AVM中可以感觉到或听到脉搏.
• Stage III (destruction): The AVM causes pain, bleeding or 溃疡.
• 第四阶段(失代偿):发生心力衰竭.

动静脉瘘(AVF)

An arteriovenous fistula (AVF) is similar to an AVM. It is an abnormal connection between an artery and a vein. 你可能天生就有AVF, 但AVF通常是在事故发生后发生的, 创伤，甚至是手术后. The goal of treating an AVF is to close down the abnormal connection between the artery and the vein. An AVF can be treated by a specialist who also treats AVMs.

症状

症状 of AVMs depend on where the malformation is located. 动静脉血栓有很高的出血风险. 随着人的成长，动静脉畸形会变得更大. They often get bigger during puberty, pregnancy or after a trauma or injury. 有动静脉畸形的人有疼痛的风险, 溃疡, 出血和, 如果AVM足够大, 心脏衰竭.

An AVM can be mistaken for a capillary malformation (often called a "port wine stain") or an infantile hemangioma.

这些是生理症状:

• 耳朵里嗡嗡作响的声音
• Headache — although no specific type of headache has been identified
• 背痛
• 癫痫发作
• 失去知觉:身体部分失去知觉
• 肌肉无力
• 视力变化
• 面瘫
• 下垂的眼睑
• 问题说
• 嗅觉的变化
• 运动问题
• 头晕
• 失去知觉
• 出血
• 疼痛
• 手指或脚趾发冷或发蓝

动静脉畸形的并发症包括:

• 中风
• 麻木:身体部分麻木
• 言语或行动方面的问题
• 儿童发育迟缓
• Hydrocephalus (accumulation of spinal fluid within the brain due to pressure on the normal spinal fluid pathways)
• 生活质量下降
• 出血死亡的风险很小

什么时候打电话给医疗保健提供者

Some people only find out about an AVM when it bleeds. 这会导致一些人中风. 如果你注意到癫痫等症状, 麻木, 呕吐或身体虚弱, go immediately to the emergency room or call 911 to get help. 然而, 任何怀疑AVM的时候, 你应该联系卫生保健提供者, 即使没有明显的症状.

诊断。

Doctors can diagnose many AVMs by reviewing the patient's history and looking at the affected area (history and physical exam). In general, AVMs are not hereditary (not passed on from parent to child).

AVMs can sometimes be mistaken for infantile hemangioma (IH). An AVM gets bigger when the child is no longer a baby. his只在婴儿期生长.

AVMs can sometimes be mistaken for capillary malformations (CMs), commonly called "port wine stains". The difference is that an AVM has fast-flowing blood in the larger blood vessels underneath the skin. The blood vessels in a CM are small and in the top layers of the skin only.

The final diagnosis, however, is usually made based on imaging tests that show areas of blood flow. An ultrasound is often the first test ordered when there is suspicion that a person might have an AVM. An ultrasound uses sound waves to make a picture of the blood vessels and tissues under the skin. It can also be used to detect the speed of blood flow, which helps doctors diagnose an AVM.

Ultrasound is a good method for young children because it doesn't require putting a child to sleep with anesthesia, 而且完全无痛.

An image of an AVM will show many winding, bending arteries and also wide veins. The blood will be seen to flow very quickly from the arteries to the veins.

MRI gives more detailed pictures of the size and location of an AVM inside the body. 核磁共振也能显示其他重要的东西, 比如神经, are near the AVM and that may be affected by treatment.

A CT scan will show whether the AVM is affecting a bone. A CT scan is like an MRI, except it uses X-rays instead of magnetic fields.

An angiogram may be ordered to give a very detailed picture of the blood vessels. 血管造影是在全身麻醉下进行的. They can be used to diagnose and "map" the blood vessels in an AVM and are also used during treatment of an AVM.

治疗

动静脉畸形是良性的，这意味着它们不是癌症. 治疗 of an AVM is focused on managing the symptoms and improving the life of the patient. There are no drugs yet that have been proven to cure an AVM.

A team of doctors will work together to treat an AVM. An interventional radiologist is a doctor who can read pictures and scans of the body and use these images to treat an AVM. This doctor will play a role in both diagnosing and treating your AVM. 外科医生也可能参与其中.

The decision to treat an AVM is made by both the doctor and the patient. 患者的年龄和AVM的大小, location and stage are all part of the decision-making process. If an AVM isn't causing problems (pain or loss of function) for the patient, then doctors may recommend just regular follow-up visits.

因为动静脉畸形会随着时间的推移而扩大, 一旦AVM开始产生问题, 医生通常会开始治疗. 如果AVM位于敏感或危险区域, doctors may discuss treatment sooner instead of waiting. Many patients with an AVM get treated when they are a child or teenager. Although some medicines are being tested for the treatment of AVM, there are no medicines that have been proven to treat an AVM.

Embolization and Sclerotherapy 治疗 for AVMs

Embolization and sclerotherapy are the most common treatments for AVM. Embolization and sclerotherapy can reduce the size and symptoms of an AVM. 他们不能让AVM完全消失.

在栓塞, 医用胶等材料, metal coils or even plugs are put into the center of the AVM through a tube called a catheter, 是通过血管插入的吗. 这些物质有助于阻止血液流动. For an AVM, embolization is often done through an artery or a vein connected to the AVM. When an AVM is blocked, blood stops flowing into it, and this helps shrink the AVM.

在硬化疗法, a liquid medicine called a sclerosant is injected into the AVM to destroy the vessels and cause scars to form. This process also leads to less or no blood flow through the AVM. Sclerotherapy is often used to treat other vascular malformations, such as venous malformations and lymphatic malformations as well.

During sclerotherapy, a doctor will use ultrasound and X-ray imaging to target the AVM.

Embolization and sclerotherapy are not cures for AVM, but rather, are used to manage AVM. 它们有助于缓解症状，使AVM变小. 随着时间的推移，AVM可能会重新扩大. Most patients get this treatment several times throughout their life. The goal is to limit the symptoms as much as possible.

Sometimes, embolization and sclerotherapy to treat AVM are done together to get the best result.

溃疡, 意思是皮肤上有开放性伤口, is the most common complication of the embolization/sclerotherapy procedure. 如果发生溃疡，你的医生会治疗它.

Another less common complication of embolization/sclerotherapy is damage to a nearby nerve. This may cause 麻木 or lack of strength and is usually temporary.

治疗准备

Your doctor and the treatment team will prepare you for what happens normally after the procedure. 他们会和你谈谈好处和风险.

通常, during the procedure the patient is asleep under general anesthesia given by a doctor called an anesthesiologist.

Some patients can go home the day of the procedure; some stay in the hospital to recover overnight or for longer.

Multiple treatments are often needed and are usually spaced about six weeks apart or more. 治疗后, 可能会有肿胀, irritation on the skin and bruising at the treated site.

对于一些动静脉畸形，手术是一种选择. 在动静脉畸形手术中，大量失血是一种风险. Embolization or sclerotherapy is sometimes done before surgery to decrease the risk of bleeding. Surgery for AVMs should be done only by surgeons with experience in treating these complicated conditions.

预防

动静脉畸形发生在出生前或出生前不久. Because their cause is unknown, you can't prevent them. The best approach is to respond quickly to the symptoms listed above.