A pulmonary arteriovenous malformation (PAVM) is a rare condition with a genetic component that affects blood flow between the heart and the lungs. When a PAVM is present, the pulmonary arteries and veins responsible for circulation are abnormally connected. Usually, arteries carry blood from the heart and to a destination organ such as the lungs, where blood moves into smaller blood vessels, called capillaries. Capillaries slow the circulation rate for optimal nutrient and gas absorption.
When an PAVM has directly connected an artery and vein, capillaries are not present. This limits how much oxygen reaches the lungs. Serious issues such as shortness of breath, bleeding, and heart failure may result from a PAVM. An pulmonary arteriovenous malformation embolization is a minimally invasive procedure that blocks the abnormal connection to reduce symptoms and the risk of complications.
Why Pulmonary Arteriovenous Malformation (PAVM) Embolization is Performed
A PAVM is usually related to a disorder called hereditary hemorrhagic telangiectasia (HHT). Patients who experience problems with nosebleeds, have visible red vein-like patterns underneath their skin, and/or have a family history of HHT should be screened for HHT. If it is suspected, a CT scan or other imaging test will be ordered to visualize the pulmonary arteries. When a PAVM is confirmed, embolization -- a procedure that cuts off blood flow to specific veins -- is usually the first line of treatment recommended for patients. When used to treat a PAVM, the approach greatly reduces a patient’s risk of future medical events.
What to Expect During Pulmonary Arteriovenous Malformation (PAVM) Embolization
PAVM embolization is performed by an interventional radiologist. After the patient is sedated through an intravenous line (IV), local anesthetic is applied to the groin area. An x-ray of the groin helps the interventional radiologist guide a catheter (thin plastic tube) from the femoral artery into the pulmonary arteries. Contrast (dye) is used to visualize possible malformations. Once the PAVM has been identified, the provider prepares an injection of embolic agents, usually tiny fibrous coils that can safely lodge themselves in the diseased area to stop blood flow to the targeted blood vessels.
Patients are typically discharged home the same day following an embolization for a PAVM. Depending on the size of the malformation, multiple procedures may be required over the period of several weeks to months.
Risks and Benefits of Pulmonary Arteriovenous Malformation (PAVM) Embolization
Embolization is a safe procedure that has many uses. The major benefit of a pulmonary arteriovenous malformation embolization in the case of a PAVM is the prevention of future serious medical events. Overall, embolization is a well-tolerated procedure that requires little downtime. Some PAVM patients report a headache following the procedure, but this typically resolves quickly. Other risks include unintended vessel damage from the catheter insertion and entry site bleeding and bruising. The usage of x-ray imaging guidance helps reduce the chance for catheter-related injury.
How to Prepare for Pulmonary Arteriovenous Malformation (PAVM) Embolization
The care team will review all current medications with the patient to identify any therapies, like blood thinners, that must be stopped prior to the procedure. This discussion will also likely include any dietary restrictions for the night before the procedure. Routine pre-procedural bloodwork may be ordered to look at the patient’s blood chemistry and the ability of the blood to clot. Patients should arrange for a ride home the day of the procedure.
Post Pulmonary Arteriovenous Malformation (PAVM) Embolization
Temporary pain following a PAVM embolization is not unusual. Any discomfort can be treated with over-the-counter pain relief. After resting for a day following the procedure, patients can resume most normal activities within a week.