The Role of Radical Surgery in the Management of Acquired Uterine Arteriovenous Malformation
A 32-year-old G3P2012 presented with sonographic findings indicating a cesarean scar ectopic pregnancy. The lower uterine segment was 6 mm thick, incorporating the bladder, uterine serosa, myometrium, decidua and trophoblast. She consented to undergo diagnostic laparoscopy, dilation and curettage. Laparoscopically, the uterine serosa appeared normal. During the curettage she had a 1.5-liter postpartum hemorrhage, which stopped after placement of an intrauterine compression balloon as a tamponade.\nThe patient subsequently presented with profuse vaginal bleeding requiring a blood transfusion. Ultrasound revealed a multicystic structure with low-resistance arterial flow on Doppler, inseparable from the anterior lower uterine segment (fig. ). MRI demonstrated multiple, enlarged vessels extending from the myometrium to the left broad ligament, which raised suspicion of an AVM (fig. ). A pelvic and selective bilateral uterine arteriography was performed. The left uterine arteriography suggested the presence of a large, high-flow arteriovenous fistula (AVF), with drainage through the left internal iliac vein and left gonadal vein. The lesion was successfully embolized with coils, and an angiogram confirmed cessation of the flow. Other multiple, small AVFs supplied by both uterine arteries were considered clinically insignificant given the occlusion of the larger AVF.\nFour days following coil placement, the patient experienced acute vaginal hemorrhage. Repeat angiography demonstrated a hypervascular midline mass arising from the anterior division of the internal iliac arteries bilaterally, without a dominant feeding artery. Angiographically, these represented multiple, small AVFs, which were larger and more numerous than those previously noted, consistent with acquired AVM (fig. ). Given her recurrence of symptoms despite vascular embolization with coils, a step-wise procedure was planned: Gelfoam (Pfizer, New York, N.Y., USA) bilateral embolization of the internal iliac arteries, followed by a hysterectomy.\nGelfoam embolization of the internal iliac arteries resulted in a 40–60% reduction in vascularity of the uterine AVM (fig. ). Grossly, the AVM originated from the prior hysterotomy site and extended into the left parametrium. The right uterine vessels and cardinal ligaments were found to have compensatory engorgement. The AVM extended into the left parametrium and left pelvic sidewall. This anatomy necessitated a radical hysterectomy for complete excision. Dissection of the potential spaces of the pelvis was undertaken, and the bladder and left ureter were dissected away from the AVM.