Vascular Malformations Overview
Vascular anomaly is a broad, generic term that refers to blood vessel abnormalities in the human body. These abnormalities can involve all different types of vessels including large arteries and veins, smaller arterioles and venules, and microsopic capillaries, as well as lymphatic channels which carry fluid that exist outside blood vessels. Abnormalities involving combinations of these channels can also exist. As a result of the breadth of involvement, vascular anomalies, as a whole, comprise a wide range of disorders from minor, cosmetically-concerning problems to organ- and life-threatening conditions.
It is imperative that the correct diagnosis is made and the appropriate therapy is sought. Historically, vascular anomalies have been a source of confusion and the terminology used to describe these conditions has been inconsistent and, at times, haphazard. Given recent advancements in scientific discovery, attempts have been made to standardize the terms used to diagnose and describe vascular anomalies. This has facilitated communication with patients as well as amongst physicians of various specialties treating these complex conditions. It is of utmost importance that the proper terminology is used to describe a given condition so as to avoid confusion during evaluation, counseling, and treatment.
The most important distinction one has to make when evaluating a vascular anomaly is to differentiate “hemangiomas” from “vascular malformations”.
Hemangiomas are mostly benign tumors of infancy that affect the cells lining the inside of blood vessels. There are various subtypes, the most common of which is the infantile hemangioma with its characteristic “strawberry birthmark” appearance. These often have a characteristic and predictable pattern of presentation and regression. Treatment is warranted to maximize normal growth and development of affected organs and to minimize cosmetic disfigurement. Other, rarer subtypes exist such as congenital hemangiomas, kaposiform hemangioendothelioma, and tufted angioma. There are also certain syndromes that feature hemangiomas as a characteristic feature such as PHACES or LUMBAR Syndromes . Proper identification and diagnosis of the specific type of hemangioma is important as expected outcomes and potential treatment options can vary. The latter include simple observation, oral medications, topical medications, laser therapy, injections, embolizations, surgery, and/or combinations thereof.
Vascular malformations, on the other hand, are not tumors. They represent abnormal development of blood vessels. Vascular malformations, while present at birth (congenital) may not become problematic until later on in life and are often triggered by an outside factor such as adolescence, puberty, pregnancy, and/or injury. Vascular malformations never regress and generally will continue to grow throughout the lifetime of the patient. Depending on which types of blood vessels are involved, associated symptoms and patterns of development vary widely. Some vascular malformations will require multiple treatments over the lifetime of the patient. It is worth emphasizing that there is no cure for the vast majority of vascular malformations and that current treatment options aim to minimize associated symptoms. Recurrence is not uncommon even after successful treatment.
As a result, regular follow-up with your doctor is essential at minimizing recurrent symptoms and associated complications. It is of utmost importance that your physician or group of physicians identifies which type of blood vessel is involved as treatment options vary widely for each type of malformation. Broadly speaking, vascular malformations are categorized based on their flow characteristics and they include:
- Capillary malformations; AKA, port-wine stains.
- Slow-flow venous and lymphatic malformations
- High-flow arteriovenous malformations (AVMs) and arteriovenous fistulas (AVF)
- Congenital mixed syndromes such as Klippel-Trenaunay Syndrome, Parkes-Weber Syndrome, Osler-Weber-Rendu Syndrome, CLOVES syndrome, Blue Rubber Bleb Nevus Syndrome AKA Bean Syndrome, and many more.
It is important to note that vascular malformations can present as isolated entities or as part of a more complex syndrome featuring multiple disorders affecting multiple organs. An organized, multi-disciplinary approach at a dedicated center of excellence is, therefore, essential for proper diagnosis and management of these challenging conditions.