Uterine Artery Psuedoaneurysm

Author Information

Ansari Munira,* Samant PY**, Parulekar SV ***
(*Assistant Professor, ** Additional Professor, *** Professor and Head of Department, Department of Obstetrics and Gynecology, Seth G. S. Medical college and KEM hospital, Mumbai, India)

Abstract

Uterine artery pseudoaneurysm is a rare cause of secondary postpartum hemorrhage occurring due to vascular trauma and inflammation of during cesarean section, vaginal delivery, curettage or hysterotomy.[1-4] We present a case of cesarean section who underwent curettage for postpartum hemorrhage and developed uterine artery pseudoaneurysm.

Introduction

Pseudoaneurysm results with extraluminal collection of blood with turbulent flow communicating with lumen of the parent vessel through a defect caused by trauma, and when connected with the uterine cavity, it causes recurrent hemorrhage.[1]  If it is surrounded by myometrium, painful hematoma results.. The 3 layers of arterial wall are absent and surrounding tissues comprise the wall.[5]  The pseudoaneurysm is prone to unpredictable rupture, and may cause fatal exsanguination.[2]

Case Report

Twenty two years old P3L2D1 underwent cesarean section in a private hospital and had severe primary postpartum hemorrhage. An emergency curettage was done. On day 17, bleeding recurred and the patient was transferred to another hospital in a state of shock. Sonography indicated retained products. Blood transfusions were started and curettage was repeated. A few placental bits were removed. On day 23, the patient had profuse vaginal bleeding. She was transfused blood and transferred to tertiary hospital. The patient was pale and febrile. She had a healed Pfannenstiel scar, bulky and soft uterus with minimal bleeding. Blood and vaginal swab and were collected for microbiologic study. Broad spectrum antibiotics were started. Her platelet count and coagulation profile were normal. Ultrasonography (USG) revealed bulky uterus with blood clots within. Antibiotics were changed as per culture report, blood was transfused. Pelvic computerized tomography (CT) scan revealed a pseudoaneurysm in the distal branch of right uterine artery and blood clots in the endometrial cavity ( figures 1 and 2). Because of strong indication of infection, obstetric hysterectomy was undertaken. On laparotomy, adhesions between the uterus and parietal peritoneum as well as surrounding viscera were noted. Due to bowel adhesions posteriorly and laterally, subtotal hysterectomy was done rather than total hysterectomy and internal iliac artery ligation was deferred. In spite of appropriate transfusions and antibiotic treatment, postoperatively the patient succumbed to septic shock.

Discussion

A pseudoaneurysm forms due to surgical trauma, inflammation, neoplasia, and infarction; with leakage of blood from an artery into the surrounding tissue with a continuing communication and is a cause of secondary postpartum hemorrhage. Common causes of secondary postpartum hemorrhage include retained products of conception, subinvolution of the uterus and hence of the placental bed, and endometritis.[6] Vascular causes include uterine vascular pseudoaneurysms, acquired arteriovenous malformations, and direct vessel rupture, usually following uterine curettage, cesarean section, hysterotomy and traumatic vaginal delivery.
    Acquired arteriovenous malformations occur following surgical trauma and consist of multiple small arteriovenous fistulas between intramural arterial branches and the venous plexus. On these appear focally or asymmetrically distributed multiple small anechoic spaces in the myometrium or endometrium with low-resistance rapid currents seen on Doppler. On USG pseudoaneurysm appears as an anechoic sac which shows turbulent arterial flow on Doppler.[3,7]. Doppler demonstrates to-and-fro sign in the neck of the pseudoaneurysm and yin yang sign in the body of the pseudoaneurysm which is diagnostic of pseudoaneurysm with a narrow neck. During systole, with higher arterial pressure, there is influx of blood into the pseudoaneurysm. In diastole the pressure in the artery drops and blood flows back through the pseudoaneurysm neck. This Doppler sign at the neck of the pseudoaneurym together with turbulent flow helps to confirm the diagnosis.[2] Pseudoaneurysm of uterine artery after cesarean section diagnosed sonographically has been reported by Henrich et al.[8]
        Accurate diagnosis of vascular etiology of delayed postpartum hemorrhage helps avoid unnecessary curettage for suspected retained products of conception and may avoid catastrophic bleeding. With the introduction of modern imaging modalities, the diagnosis of uterine artery pseudoaneurysm has become easier.[1,2,4,5]  USG, CT and magnetic resonance imaging are being used more frequently as initial diagnostic modalities.[9] Angiography remains the gold standard in diagnosing and treating vascular malformations. Brown et al reported an early case of selective arterial embolization used successfully to treat an extra uterine pelvic haematoma after three failed surgical attempts.[10] The success rate following embolization is around 97%.[11] In a study of efficacy of uterine artery embolisation, Young Ho Choi reported 90% overall success rate, the least being with secondary PPH and 10% complications.[12] The reported success rates for internal iliac artery ligation vary from 42%-100% because of the extensive pelvic collateral circulation.[13] Dasari et al reported a case of hemorrhage on the 23rd day due to pseudoaneurysm after cesarean section treated by bilateral internal artery ligation.[14] Embolization of a uterine arteriovenous pseudo aneurysm following arteriovenous fistula in a case of hysterectomy has been reported by Ferguson et al.[15]
AV malformation including pseudoaneurysm should be suspected in intractable or recurrent delayed postpartum hemorrhage. Angiographic embolization of pseudoaneurysm has the advantage of low morbidity, easy bleeder localization, more distal occlusion than ligation, and preservation of fertility. Timely diagnosis and appropriate intervention can prevent infection related morbidity.

References

1.      Cooper B., Hocking-Brown M., Sorosky J, Hansen W. Pseudoaneurysm of the Uterine Artery Requiring Bilateral Uterine Artery Embolization. Journal of Perinatology (2004) 24, 560–562.
2.      Lee W, Clare J., Roche C, Duddalwar V, Buckley A, Morris C, Pseudoaneurysm of the uterine artery after abdominal hysterectomy: Radiologic diagnosis and management  (Am J Obstet Gynecol 2001;185:1269–72.)
3.      Mou et al. Giant uterine artery pseudoaneurysm after a missed miscarriage termination in a cesarean scar pregnancy. BMC Women's Health 2014, 14:89  http://www.biomedcentral.com/1472-6874/14/89
4.      Kwon JH, Kim GS. Obstetric iatrogenic arterial injuries of the uterus: Diagnosis with US and treatment with transcatheter arterial embolization. Radiographics. 2002 Jan-Feb;22(1):35-46.
5.    Lenartova M,Tak T, Iatrogenic Pseudoaneurysm of Femoral Artery: Case Report and Literature Review. Clinical Medicine & Research Volume 1, Number 3: 243-247
6.      Khong TY, Khong TK. Delayed postpartum hemorrhage: A morphologic study of causes and their relation to other pregnancy disorders. Obstet Gynecol 1993;82:17-22.
7.      HuangMW, Muradali D, ThurstonWA, Burns PN,Wilson SR. Uterine arteriovenous malformations: gray-scale and Doppler US features with MR imaging correlation.Radiology 1998; 206:115-23.
8.      Henrich W, Funchs I, Luttkus A, et al. Pseudoaneurysm of the uterine artery after caesarean delivery. J Ultrasound Med.2002;21:1431–4.
9.      Grivell M, Reid M, Mellor A. Uterine arteriovenous malformations: a review of current literature. Obstet Gynecol Surg. 2005;60(11):761-767.
10.  Brown BJ, Heaston DK, Poulson AM, et al. Uncontrollable postpartum bleeding; a new approach to hemostasis through angiographic embolization. Obstet Gynaecol. 1979;188:183–7.
11.  Vedanatham S, Goodwin SC, McLucas B, et al. Uterine artery embolization. An underused method of controlling pelvic haemorrhage. Am J Obstet Gynaecol. 1997;176:938–48.
12.  Young Ho Choi, Yasutaka Baba, Shunichiro Ikeda, Young Ho So, Sadao Hayashi, Masayuki Nakajo. Efficacy of Uterine Artery Embolization for Patients with Postpartum Hemorrhage. Open Journal of Radiology, 2013; 3: 51-55 (http://www.scirp.org/journal/ojrad)
13.  Gary A. Dildy III. Post partum hemorrhage : New Management Options. Clin Obstet Gynecol 2002; 45(2):330-344.
14.  Dasari P, Maurya DK. Uterine artery Pseudoaneurysm: a rare cause of secondary postpartum haemorrhage following caesarean section. BMJ Case Reports. 2011
15.  Ferguson D., Morris G., Odurny A., Ferguson J. and Phillips M. Endovascular Therapy for Arteriovenous Pseudoaneurysm of the Uterine Vessels. EJVES Extra 6, 49–51 (2003)
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Citation

Ansari Munira, Samant PY, Parulekar SV. Uterine Artery Psuedoaneurysm. JPGO 2014 Volume 1 Number 12 Available from: http://www.jpgo.org/2014/12/uterine-artery-psuedoaneurysm.html