SCREENING

There are several tests available for everyone who is known or suspected to have HHT. Since lung and brain AVMs can cause serious damage without warning, and they can be successfully treated, testing is strongly suggested for these AVMs. Testing for brain and lung AVMs is often referred to as ’screening’, meaning the AVM is looked for prior to its causing a problem.

To screen for brain AVMs, an MRI with and without gadolinium is recommended. It is currently recommended that a brain MRI only needs to be done once early in life and once as an adult, if it is normal. Most brain AVMs are thought to be congenital (present at birth).

Screening for lung AVMs is dependent on the age of the individual, and to a lesser degree their symptoms. During childhood, oxygen saturation should be checked every one to two years by finger oximetry done in both lying and sitting positions. Any subnormal result should be followed up with appropriate diagnostic testing. At 10-12 years of age, more sensitive screening should be done to rule out lung AVM(s). Currently in North America, a contrast echocardiogram (echo bubble) is usually recommended to screen for lung AVM in adults. It is a very sensitive test (meaning it will miss very few lung AVMs), but everyone with a ‘positive’ or ‘abnormal’ echo bubble test does not have a lung AVM large enough to require treatment. To determine who requires treatment by an embolization procedure, a chest CT scan is usually done to follow-up on a positive echo bubble test. If a pregnant woman has not recently been evaluated for lung AVMs, it is imperative to screen for lung AVMs as soon as pregnancy is recognized. Preferably, individuals with HHT will have screening for lung AVMs before pregnancy.

Lung and brain AVMs are the only problems associated with HHT for which pre-symptomatic screening is routinely recommended. Most insurance companies will pay for these recommended screening tests if a brief explanation of the association between HHT and AVMs in these internal organs is provided. Until lung AVMs are excluded by this testing, a person known or suspected to have HHT should follow the American Heart Association guidelines (see Dental Care-Important Precaution) for taking antibiotics before all dental cleaning or work. This is to prevent brain abscess, which occurs when bacteria in the mouth enter the bloodstream during dental work or cleaning and passes through a lung AVM to the brain.

Other than in the brain and lungs, HHT can be treated as the symptoms warrant. With this in mind, a yearly evaluation by a physician familiar with the wide spectrum of symptoms associated with HHT is recommended, along with an annual check of hematocrit/hemoglobin.

Treatment

Although there is not yet a way to prevent the telangiectases or AVMs from occurring, most can be treated once they occur. They should be treated if they are either causing a significant problem (as in the case of frequent nosebleeds) or if they are at high risk of causing a serious problem (such as a stroke from a lung AVM). The recommended treatment for a telangiectasia or AVM depends on both its size and location in the body.

Bleeding from telangiectases in the nose sometimes responds satisfactorily to some everyday practical treatments implemented at home. Humidification of the air and use of an ointment on the lining of the nose help keep the mucous membrane of the nose moist and can reduce nosebleeds. There are products sold over-the-counter in pharmacies or pharmacy sections of big stores that can be used to help control nosebleeds when simple pressure applied to the outside of the nose isn’t enough. Click on the following link for more information on Nosebleed Self-Help: Nosebleeds Self Help PDF

If these home management techniques do not result in a satisfactory control or reduction in nosebleeds, the first medical treatment that should usually be considered is laser therapy. Laser coagulation therapy is preferable to electric and chemical cautery primarily because- if done carefully by an ENT physician with specific expertise in both laser therapy and HHT- it has less risk to damage the inside of the nose. A small beam is directed around the margins of each telangiectasia and photocoagulation occurs. Most patients who undergo laser therapy see significant improvement for a period of time, but it usually needs to be repeated periodically. Because the procedure has little risk of harming the nose if done by an experienced physician, it can be repeated as needed.

Septal dermoplasty is another treatment option for severe nosebleeds, and is usually considered when laser therapy has repeatedly failed to help. Septal dermoplasty replaces the thin lining of the nose (called the mucous membrane) with a thicker graft of skin. When performed by an ENT (Ears, Nose, and Throat) physician knowledgeable and experienced with the Saunder’s method, it can significantly reduce the frequency and severity of nosebleeds. It is a more drastic treatment than laser in that it permanently removes the natural lining of nose and replaces it with skin. Daily care and attention to the nose is required after septal dermoplasty to keep the nose moist and clean. Some studies have shown hormonal therapy to be helpful in some patients for whom the local therapies (i.e. home moisturizing care and laser therapy) have not been successful.

Embolization (blocking off an artery) can be used to halt severe nose bleeding that has been unresponsive to other treatments, but is usually only effective for 6-8 weeks. Other arteries enlarge and cause recurrence of the bleeding. This therapy for the nose is generally used only on an emergency basis and is generally only a temporary measure.

Telangiectases of the skin can also be treated with laser therapy if they bleed to an extent that is bothersome or if the telangiectases are a cosmetic concern. Lesions of the skin are usually best treated by a dermatologist who has particular expertise in the use of lasers.

Bleeding from the stomach or intestines is generally treated only if it causes anemia (low blood count). Iron replacement therapy is the first line of defense. Iron is usually first given orally (a tablet by mouth), but can be given intravenously (IV) if the oral iron is not tolerated by a patient, or if the oral iron is not getting enough iron into the body. If iron therapy can not control the anemia, transfusion and endoscopic treatments using a heater probe, bicap, argon photocoagulation or laser are options. Hormonal treatment has also been helpful in some people.

Lung and brain AVMs should be treated before they cause symptoms or problems in most cases. This is why testing or screening for them is recommended in all individuals with HHT, regardless of their specific symptoms. Lung AVMs can almost always be treated completely and permanently using an outpatient procedure called embolization. An Interventional Radiologist inserts a small tube (catheter) in a large vein in the groin. The tube is then passed through the blood vessels system to the AVM in the lung. A devise (a ‘coil’ or occasionally a ‘balloon’) is placed in the artery leading to the AVM to stop blood flow through the AVM. The procedure usually takes 1-3 hours and requires only a few hours of recuperation.

Brain AVMs are treated in different ways depending on the size, structure and location in the brain of the abnormal blood vessels. Surgery, embolization and stereotactic radiosurgery can all be used, separately or in combination, to successfully treat brain AVMs.

Liver AVMs are currently treated only if a patient shows signs of liver or heart failure, as a result of their liver AVM. Embolization, which is so successful for the treatment of pulmonary AVMs, can cause severe complications when performed in the liver. Decisions regarding treatment of liver AVM are made on a case by case basis and should be managed by a physician very familiar with the liver manifestations of HHT.