What Are Combined Vascular Malformations?
A combined vascular malformation involves two or more types of blood and / or lymphatic vessel abnormalities. Any of the four types of vessels (capillary, venous, lymphatic, or arteriovenous) may be combined. Combined malformations are often located on the arms or legs, but can involve any area of the body. The abnormal vessels develop early in pregnancy. They are thought to be caused by incorrect formation of the circulatory system (blood vessels and lymphatic channels) in a particular area of the body. Most combined vascular malformations are not inherited.
Diagnosis of Combined Vascular Malformations
Combined vascular malformations are generally able to be diagnosed by a patient’s history and physical examination. Sometimes large lesions can be seen on prenatal ultrasound. Radiologic imaging such as ultrasonography, magnetic resonance imaging (MRI), or computed tomography (CT or CAT scan) may be needed to confirm diagnosis or to see the extent of the malformation. Plain X-rays allow doctors to see if and how the malformation affects bone growth.
Complications vary with the size and type(s) of vessels involved in the malformation. More complications tend to occur when the malformation is large and when more types of vessels are involved. Lymphatic blebs (blister-like lesions) may leak lymphatic fluid or bleed. Abnormal lymphatic vessels increase the risk of infection in the area of malformation. Abnormal veins may cause pain, swelling, clotting problems, or early fatigue and heaviness of the affected limb.
In combined lesions with an arteriovenous malformation, the major concerns are due to the abnormal flow of blood from arteries into veins. Normally, blood does not flow directly from an artery to a vein. This may cause pain, skin breakdown, tissue loss and / or overgrowth of the affected area on the body. Combined lesions with arteriovenous malformation may lead to heart problems.
Treatment of Combined Vascular Malformations
All patients require evaluation by a multidisciplinary team with expertise in management of complex vascular malformations. Treatments depends on the type of abnormal vessel(s) involved and the issues and / or concerns of the patient. Treatment approaches often require different types of specialists to work together.
Many malformations are treated with compression garments. Complex lesions may require medications, sclerotherapy, embolization, and / or surgical excision. For combined malformations, treatment plans often combine a variety of these approaches over time. For more information on these approaches, refer to the information on capillary, venous, lymphatic, and arteriovenous malformations.