Failed angiographic embolization in uterine arteriovenous malformation: A case report and review of the literature

Uterine arteriovenous malformation (AVM) is a rare condition, with fewer than 100 cases reported in literature.[1] It is seen as heavy vaginal bleeding, which may be postpartum, postabortion, or menstrual and which is usually refractory to conventional therapies. The onset and cessation of bleeding are abrupt, something like the opening and closing of a faucet. Uterine AVMs may be congenital or acquired. Congenital AVMs have multiple vascular connections, may manifest at other sites, and involve surrounding structures, whereas acquired AVMs usually have a single connection between an artery and a vein.[2] Acquired AVMs may be preceded by uterine curettage, cesarean section, gestational trophoblastic neoplasia, or endometrial carcinoma. Pregnancy is thought to play a role in their pathogenesis. Chorionic villi necrosis followed by incorporation of venous sinuses in scarred myometrial areas may lead to formation of an AVM. AVMs are hormone-responsive and congenital AVM may manifest at puberty or after a pregnancy.[3] AVMs may be diagnosed by Doppler ultrasonography, computed tomography, magnetic resonance imaging, and angiography. On hysteroscopic examination, the subsurface of the endometrium appears to have a tangled pulsatile mass of irregular bluish-purple distended vessels that differ markedly from the normal vasculature, which has a fine-capillary net pattern.[2] Management depends on hemodynamic stability and the amount of bleeding as well as on the patient's age and her desire to preserve fertility. Some years ago, hysterectomy was performed for symptomatic AVMs, especially if fertility was not a concern. In the last decade, an increasing number of women have been treated conservatively with success and hysterectomy is no longer considered essential. Acute management includes measures to stabilize the patient, uterine tamponade with Foley's catheter or rolled gauze packing, and medical therapies like estrogens, progestins, methylergonovine, danazol, and 15-methyl-prostaglandin F2alpha.[2,4,5] In stable women, expectant management, surgical removal of an AVM, laparoscopic bipolar coagulation of the uterine blood vessels, and long-term medical therapy with combined oral contraceptive pills are reported.[6–10] Coagulation of the AVM may also be done under hysteroscopic guidance with a neodymium:yttrium-aluminum-garnet laser fiber held several millimeters above the AVM (without touching the AVM) using a power of 50 to 60 watts. Such treatment may be repeated 2 to 3 times (at monthly intervals) until the AVM disappears completely. There are, however, reports of hysteroscopy being abandoned because of heavy blood loss during the procedure and therefore its value is limited.[2] Another treatment modality is selective uterine artery embolization, which has been used successfully for treating AVMs in emergency settings and when other treatment modalities have failed. Although it may not always succeed and subsequent treatment may be required, selective uterine artery embolization is currently considered the treatment of choice in women of all age groups.[2,11,12]