Irregularities in arteries, veins or lymph vessels throughout the body can cause serious problems—even leading to strokes. Called vascular malformations, they are usually present in a person from birth or may be detected after many years, even as late as the 30s or 40s. 

Many of these so-called vascular malformations are diagnosed using magnetic resonance imaging (MRI), ultrasound and/or computerized tomography (CT scan). These studies enable doctors to better see the structure of affected and nearby blood vessels. 

Yale Medicine has expertise in vascular malformations, including hereditary hemorrhagic telangiectasia. We use some of the most advanced imaging technology to help care for patients with vascular malformations.

Vascular malformations may cause several different symptoms, depending on the specific irregularity and where they are in the body, says interventional radiologist Jeffrey S. Pollak, MD, He is the director of Yale Medicine's HHT Program. 

Symptoms can include pain, a lump under the skin, ulcers, bleeding, shortness of breath or neurological disturbances such as stroke, headaches or seizures. Some patients with vascular malformations may not have symptoms. 

Venous malformations affect the veins and typically cause pain and/or a lump under the skin and/or a birthmark.

Lymphatic malformations affect the lymph vessels and may also cause lumps and/or birthmarks and bleeding or lymph fluid leakage. Lymphatic malformations can become infected and require antibiotics.

Arteriovenous malformations affect arteries and may cause pain, stress on the heart and bleeding. In addition, specific symptoms can be related to the organ involved.

Pulmonary arteriovenous malformations are AVMs in the lungs. These permit the escape of blood from one side of the heart system to the other without picking up oxygen from the lungs or trapping of possible clots or bacteria in the smaller normal lung circulatory system. This can result in the risks of stroke or brain abscess (from clots or bacteria escaping through the lungs and lodging in brain vessels), fatigue and shortness of breath and sometimes the coughing up of blood or blood in the chest.

People are referred for diagnosis of vascular malformation when they display suggestive symptoms, when other family members have a known inheritable vascular malformation and/or when earlier CT or MRI imaging indicates a possible problem.

“Children of patients with hereditary hemorrhagic telangiectasia have a 50 percent chance of having a malformation themselves,” says Dr. Pollak.  “These children are screened for lung AVMs in their teen years, but if they’re symptomatic, they may be screened earlier.”

Dr. Pollak, who sees over 50 patients a year at Yale Medicine’s HHT Center, says that during the first visit there is a discussion with the patient and the patient’s family, followed by an initial evaluation, going over previous imaging and other tests.

“If we strongly suspect someone in particular has a lung vascular malformation that should be treated, we typically will have the visit the first day and treatment the next,” Dr. Pollak says.

During treatment, the patient is moderately sedated and made comfortable, while semi-awake. For the angiogram, a catheter is inserted into the groin area, and moves up to the right side of the heart and the lungs, at which time X-ray dye is injected. As the site of the malformation becomes visible, the catheter is moved to the affected vessel and a blocking agent is introduced through the catheter to stop the flow of blood to that lung vessel.

Dr. Pollak says that the procedure can take one to three hours, depending on how complicated the malformation is.

Yale’s Hereditary Hemorrhagic Telangiectasia Center was the first of its kind in the world when it was established in the 1990s, and Dr. Pollak’s renowned research in the field informs his work as an interventional radiologist. His team provides its patients with informed, compassionate care using the most advanced technology available.