Arteriovenous malformation is an abnormal and direct connection between arteries and veins as capillaries failed to develop normally. Blood from high-pressure arteries flows directly through low-pressure veins, elevating the venous pressure dangerously high. This further results in venous congestion and venectasia When severe, it may cause ulcer and extremely severe pain from ischemia of the tissue and damage the heart, leading to heart failure. This condition can occur in any part of the body including the head, the neck, the thorax, the extremities, the abdomen, and the organs.
Symptoms
Patients with arteriovenous malformations tend to visit a doctor after feeling pain or finding a pulsating lump. With high pressure, the lesion feels tight, and sometimes the condition is misdiagnosed as varicose veins when accompanying venectasia. Also, capillaries may seem too much visible under the skin and the leg or the arm with the lesion may become larger or longer than the other side. The site near the lesion is warmer than the rest and sometimes covered with many hairs. When it is severe, abnormal vessels with high pressure may grow into the bone, damaging it. Patients who have suffered this condition for a long time develop heart conditions and in the end experience heart failure, making them panting after even a mild exercise. If the lesion is deep in the abdomen, organs, or the thorax, it is invisible outside and asymptomatic and may be found by chance.
Treatment
This disease can be diagnosed simply based on patients’ history and clinical features. However, for an accurate diagnosis and an effective treatment, patients go through various tests to determine the position of the lesion, its interactions with surrounding organs, and its growth into the bone.
When the lesion is small enough, it can be surgically eliminated, but mostly it is too large to remove completely. Therefore, in most of the cases alcohol (ethanol) sclerotherapy is applied. Ethanol is a powerful agent. When it is injected into a blood vessel, it destroys vessel cells and induces an acute thrombus. As ethanol causes severe pain when injected, patients receive general anesthesia. Through angiography, haemodynamic conditions are precisely determined. Then, a thin catheter is inserted into the vessel and up to the lesion. There, an embolic agent is injected to block the circulation. While ethanol is a popular agent, it is significantly toxic in the vessel. Therefore, this treatment should be conducted by well-experienced specialists. Other than ethanol, coils can be used to block the vessel, too.
The number or the size of the lesions that can be treated at a time is limited and the quantity of ethanol is also limited based on the patients’ weight and conditions. As a result, patients are treated several times and a complete recovery after a single treatment is hardly expected.
Prognosis
When patients are well treated as planned, they will notice less pain. When the condition is almost completely treated, strong pulsation will become as weak as in other healthy part of the body. In the long run, the risk of heart failure will decrease and dilated veins will become smaller. Bleeding and ulcer will become less serious and patients won’t feel uncomfortable anymore.
Complications
Adverse effects can be minimized when ethanol is treated in the vessel only by highly skilled and well-experienced specialists. As ethanol is highly toxic in the vessel, it may cause skin damage, necrosis, or paralysis. The complications can be also treated by our specialized teams like the Physical and Rehabilitation Medicine Department or the Plastic Surgery Department in our multidisciplinary network.