Arteriovenous Malformations and Other Vascular Malformation Syndromes

Abstract

Vascular malformations are a disruption of the normal vascular pattern in which it is expected that a capillary network of microscopic vessels lies interposed between high-pressure arteries that deliver blood and thin-walled veins that collect low-pressure blood for return to the heart. In the case of arteriovenous malformations, arteries or arterioles connect directly to the venous collection system, bypassing any capillary bed. Clinical consequences result from rupture and hemorrhage, from dramatically increased blood flow, or from the loss of capillary functions such as nutrient exchange and filtering function. These malformations can occur sporadically or as a component of inherited vascular malformation syndromes. In these and other hereditary vascular malformation syndromes, genetic studies have identified proteins and pathways involved in vascular morphogenesis and development. A common theme observed is that vascular malformations result from disruption in pathways involved in vascular stability. Here we review the vascular malformations and pathways involved in hereditary hemorrhagic telangiectasia, capillary malformation-arteriovenous malformation, cerebral cavernous malformations, and mucocutaneous venous malformations.

The Use of Sodium Tetradecyl Sulphate for the Treatment of Venous Malformations of the Head and Neck

“…A modified scheme (Table 1), described by Neville [1] divides vascular malformations into: (a) simple (capillary, venous, lymphatic, arteriovenous) or (b) a combination of two or more of the previous categories. Others classify vascular malformations as low flow (capillary, venous and lymphatic malformations or a combination of them) and high flow (arterial and arteriovenous shunt) [1][2][3]. Previous literature reports an incidence of 14-65 % of vascular malformations occurring in the head and neck region [4].…”

“…These lesions normally don't involute, but continue to increase in size in proportion with body size, often reaching enormous volumes [4]. In contrast, Hemangiomas are active proliferating tumors which demonstrate a characteristic pattern of rapid postnatal growth followed by slow involution [2,3]. Although the serendipitous discovery of the therapeutic efficacy of propranolol in the management of infantile hemangiomas has revolutionized the care and outcomes of these lesions [5,6], there is no standard treatment protocol for the management of VM.…”

Constitutively active Notch4 receptor elicits brain arteriovenous malformations through enlargement of capillary-like vessels

“…Genetic deletion of each of these genes has revealed that they are required for normal vascular development and prevention of AVM formation (6)(7)(8). Mutations in SMAD4, RASA1, and PTEN have also been linked to AVMs in humans (9,10), and mutations in Rasa1 lead to AV shunting in zebrafish (11).…”

Chronic Leg Ulcer Due to Arteriovenous Malformation: A Case Report

“…(3) Direct connection of arteries or arterioles to the venous system without any capillary bed can be described as arteriovenous malformation and it can be occured sporadically or as a component of inherited vascular malformation syndromes. (4) Arteriovenous malformations may exist for many years without symptoms. (5) Symptoms of fistulas due to malformation differ from congestive heart failure to distal leg ischaemia result to ulcer formation.…”