This column summarizes patient cases posted to SIR Connect (SIR’s popular online member community), the responses from other SIR members and how that feedback helped the original poster. To see how SIR’s online community can help you, visit SIR Connect at connect.sirweb.org.
Original post
This week I will be seeing a 38-year-old in consult for uterine AV fistula/shunt.
Patient had dilation and curettage for blighted ovum early December of 2018. In the interim, the patient has intermittent bleeding (previously her cycles were normal) and persistent right lower quadrant pain. Current Hgb is 11.5, it was 13.8 prior to D/C. Patient does not want a hysterectomy.
Questions:
Bead size? I was planning on approaching the case like a UAE for fibroids. 500–700 um and upsize if needed. If one of the uterine arteries does not supply the nidus, should I treat? Source for collaterals in future. Follow-up imaging: Was considering US at six months intervals for a year?
—Fawzi Mohammad, MD
Read the full discussion thread.
1. Author background and current practice preferences for uterine AV fistula/shunt management
Our private practice includes four vascular and interventional radiologists who cover two hospitals. We have a vibrant IR practice and perform uterine artery embolization for fibroids regularly and often treat postpartum hemorrhage.
2. What prompted you to reach out regarding this case?
I reached out to SIR Connect because I had not encountered this case in our practice or recalled seeing a similar case during residency or fellowship. Also, there were not many good research articles about the topic.
3. What post or posts were most valuable to you?
The patient did not want a hysterectomy and was apprehensive about undergoing any surgery or procedure because she experienced a postprocedural bleed after her dilation and curettage. All the posts were very useful, with advice ranging from treating the lesion aggressively to conservative management.
4. How would you have approached this question in the absence of SIR Connect?
I would have reached out to friends and colleagues in IR; however, that might have taken a longer time to receive a response. SIR Connect is very useful since one usually gets feedback quickly. This is a major factor as sometimes add-on inpatient cases require prompt decisions.
5. Do you find that the responses will shape your practice pattern and lead to an outcome that you did not think could have been achieved otherwise?
In this particular case, the end result would have been the same regardless of SIR Connect. When I saw the patient on consult, the bleeding had stopped. We also followed up with the patient after 10 days and there was persistent cessation of bleeding. No follow-up imaging was obtained. We were reassured by the fact that one of the SIR Connect responders had similar scenarios with several patients. Our department does not currently carry glue but we are considering stocking it in case we see a similar case.
Additional commentary
Figure 1. A) Grayscale US demonstrating hypoechoic structures representing a uterine AVM. B) Color Doppler US demonstrating turbulent vascular flow in the region of the uterine AVM. C) Contrast-enhanced MRI demonstrating serpiginous uterine vessels. D) Contrast-enhanced CT demonstrating serpiginous uterine vessels.
Acquired uterine arteriovenous malformations (AVMs) are abnormal communications between the arterial and venous system that bypass the capillary bed and can exist with or without a central nidus.1,2 These lesions often present after obstetric and gynecologic procedures including dilation and curettage, cesarean-section, myomectomy, manipulation/instrumentation, placental delivery, or in the setting of spontaneous abortion and existing pathology such as gestational trophoblastic disease.2
Diagnostic imaging often involves color Doppler ultrasound where uterine AVMs generally appear as tubular, hypoechoic structures with turbulent blood flow (Figure 1) and low resistive indices.2,3 The interventional radiologist should be aware that subinvolution of the placenta and andenomyosis can have a similar appearance on this modality. Magnetic resonance imaging (MRI) can differentiate uterine AVMs, which characteristically show serpiginous vessels (Figure 2) extending into the uterine myometrium.2 CT may demonstrate similar features. Alternatively, angiography of a uterine AVM will demonstrate early venous filling and may identify a central nidus, and may be both diagnostic and therapeutic.2
Patients with acquired uterine AVMs can experience vague pelvic and urinary symptoms but most commonly present with intermittent menorrhagia and metorrhagia, with both mild intermittent bleeding and large hemorrhage observed.2,4 Nearly half of patients experiencing hemorrhage in the setting of a uterine AVM may require blood transfusion.2,5 Although these lesions have been reported to regress spontaneously6, persistent bleeding often requires surgical intervention involving partial or complete hysterectomy.2
Image-guided embolization has emerged as an alternative to surgical intervention, especially in women of childbearing age who wish to maintain fertility. Although successful pregnancy is reported following embolization, subsequent placental abnormality remains a potential concern.2 In a relatively recent systematic review combining case reports and a single retrospective study, Yoon et al. included 54 patients who underwent transcatheter embolization for symptomatic acquired uterine AVMs and reported a success rate of 61% for primary symptomatic control with repeat treatment resulting in a secondary success rate of 91%.2 Approximately 85% of patients experienced symptom resolution when embolization was combined with medical therapy.2 Historically, various combinations of embolic agents have been reported with Gelfoam, glue, coils, polyvinyl alcohol and microspheres used most commonly.2 Subsequently, retrospective studies by Picel et al. and Barral et al. have reported the safety and efficacy of n-butyl cyanoacrylate (NBCA) and ethylene vinyl alcohol copolymer (Onyx), respectively.7,8 No direct comparison between embolic agents has been performed.
In this case, numerous respondents offered anecdotal experience, suggesting embolization with Gelform sclerosant, coils or glue via angiography or direct ultrasound-guided access. Potential dual supply from uterine and ovarian vessels was highlighted along with venous shunting, which limits the use of particle embolics. Alternatively, respondents suggesting conservative management offered clinical follow-up and serial ultrasound surveillance.
Given the self-resolution of the patient’s symptoms and her desire to avoid another procedure or surgery, the interventional radiologist decided to reassess the patient and defer embolization. As stated in response #5 above, this decision-making was supported by the SIR Connect responders who shared personal history of self-resolution with observation. The patient, referring service and interventional radiologist were reassured on continual follow-up, highlighting the importance of pertinent negative signs and the role that patient preference plays in interdisciplinary decision-making.
Fawzi Mohammad, MD, describes the value of SIR Connect to his practice of IR.
References
- Lowe LH, Marchant TC, Rivard DC, Scherbel AJ. Vascular malformations: Classification and terminology the radiologist needs to know. Semin Roentgenol. 2012;47(2):106–117.
- Yoon DJ, Jones M, Taani JA, Buhimschi C, Dowell JD. A systematic review of acquired uterine arteriovenous malformations: Pathophysiology, diagnosis, and transcatheter treatment. AJP Rep. 2016;6(1):e6–e14.
- Ore RM, Lynch D, Rumsey C. Uterine arteriovenous malformation, images, and management. Mil Med. 2015;180(1):e177–180.
- Molvi SN, Dash K, Rastogi H, Khanna SB. Transcatheter embolization of uterine arteriovenous malformation: report of 2 cases and review of literature. J Minim Invasive Gynecol. 2011;18(6):812–819.
- Peitsidis P, Manolakos E, Tsekoura V, Kreienberg R, Schwentner L. Uterine arteriovenous malformations induced after diagnostic curettage: a systematic review. Arch Gynecol Obstet. 2011;284(5):1137–1151.
- Ghizzoni V, Gabbrielli S, Mannini L, et al. Spontaneous resolution of an acquired uterine arteriovenous malformation in an elderly primigravida. Am J Case Rep. 2018;19:1140–1145.
- Picel AC, Koo SJ, Roberts AC. Transcatheter arterial embolization with n-Butyl cyanoacrylate for the treatment of acquired uterine vascular malformations. Cardiovasc Intervent Radiol. 2016;39(8):1170–1176.
- Barral PA, Saeed-Kilani M, Tradi F, et al. Transcatheter arterial embolization with ethylene vinyl alcohol copolymer (Onyx) for the treatment of hemorrhage due to uterine arteriovenous malformations. Diagn Interv Imaging. 2017;98(5):415–421.
