TEMPLATE DESIGN © A case of massive primary postpartum haemorrhage with previous myomectomy and a possible arteriovenous malformation M Islam, D Subramanian King’s College Hospital, London, UK Uterine AVMs (continued) In contrast with true aneurysm, pseudoaneurysm lacks the three arterial layers (tunica intima, media and adventitia). The false aneurysm communicates with the main parent artery through the injury to that artery. Aetiology Types of surgery that can to lead to pseudoaneurysm formation: Caesarean section Surgical TOP Laparoscopic myomectomy Open myomectomy (our case) Laparoscopic ovarian cystectomy Uterine currettage SVD Clinical presentations of pseudoaneurysm of the uterine artery: History of previous uterine surgery Brisk fresh vaginal bleeding Recurrent admissions with postpartum haemorrhage Failure to respond to uterine evacuation or medical therapy Diagnostic tests Ultrasonography (Figures 6 & 7): o Non- invasive; o Diagnostic when used with colour Doppler; o Widely available therefore can identify pathology at first presentation; o Can localise source of haemorrhage, in preparation for therapeutic angiographic procedure Angiography: o Gold standard; o Very effective in defining vascular anatomy and treating uterine vascular abnormalities; o Can be combined with treatment procedure MRI, CT Caesarean section is frequently found to be associated with the formation of vascular abnormalities. This can be due to lateral extension of the lower uterine segment incision and failure to secure the apex of an extension during repair. However, pseudoaneurysms have also been reported even after normal vaginal delivery (usually occurring within the myometrium). Figure 6 (taken during systole) Background Postpartum haemorrhage (PPH) is a leading cause of maternal mortality worldwide. It still presents a major challenge to obstetricians and there has been increasing awareness of the diagnosis and management of rare causes of intractable uterine bleeding from arteriovenous malformations (AVM) involving the uterine vasculature. Rupture of a pseudoaneurysm usually presents as secondary PPH, but often remains unrecognised. Diagnosis is frequently delayed by lack of familiarity with the condition. Women typically undergo a variety of interventions, such as uterine evacuation for insignificant amounts of retained products of conception, blood transfusion, antibiotic treatment or even hysterectomy before the definitive diagnosis is made. The postpartum period can be a time of psychological upheaval for women and their families hence every effort should be made to find the definitive cause of PPH. We report a case of a 38 year old primiparous women with a previous history of open myomectomy which involved the removal of multiple fibroids, the largest measuring13 cm in the posterior uterine wall. The cavity was not breached. Antenatal events Early dating scan showed gestational sac implanted high in the endometrium in the anterior aspect of the cavity and asymmetrically thickened and dilated blood vessels were seen on the posterior wall. The significance of this finding was not clear (figures 1,2 and 3). Patient Case Report Figure 2 Figure 3 Figure 1 22 week scan showed the placenta was high & anterior (away from site of AVM) Uneventful pregnancy other than one admission for minor vaginal bleeding at 32/40. Labour Spontaneous labour at PVB ++ at full dilatation leading to easy Kiwi ventouse delivery. Ongoing heavy bleeding, not responding to uterotonics. 3-4cm left lateral cervical tear extending posteriorly at the level of pouch of douglas leading to massive postpartum haemorrhage of 5 litres and DIC. Extensive suturing and transfusion of blood products.. Admitted to intensive care unit with vaginal pack. Returned to theatre for re-suturing and pack removal the following day. Gynae clinic (10 months post delivery) On scan: 2cm aneurysmal dilatation of a vessel was seen deep in the posterior myometrium on the right side of the uterus where the fibroid was previously removed. AVM was thought unlikely to be the direct cause of PPH, although the blood supply to the uterus may have been relatively increased. Risk of bleeding secondary to the AVM in the next pregnancy is increased, should the pregnancy implant posteriorly and the placenta be deeply invasive. Referred to interventional radiology for embolisation. Awaiting MRI prior to this. Case Report (continued) Figure 4 Uterine AVMs Vascular abnormalities that lead to abnormal uterine bleeding include: Congenital or true AVM Acquired or false AVM, or pseudoaneurysm Trauma to the uterine arteries is thought to be the commonest cause of pseudoaneurysm. Uterine AVMs have a distinct angiographic appearance, depending on their type. re5 References On grey-scale ultrasound, a pseudoaneurysm may appear as a heterogeneous, well outlined haematoma lateral to the uterus. Colour Doppler will demonstrate blood flow within the lesion and a ‘to-and-fro’ phenomenon. Treatment The condition is self limiting if the natural healing process has managed to seal the injured artery permanently. However, if bleeding persists and intervention is required, management should involve a multidisciplinary approach. Interventional radiology and embolisation of the vessel remains the main tool for definitive treatment. Advantages of UAE: Found to be successful in arresting PPH Minimally invasive Requires only local anaesthesithetic Preserves the uterus If the site of haemorrhage can be accurately identified, it can be performed with minimal disruption of the normal vascular supply to the uterus. May show alternative, unsuspected sources of haemorrhage from other branches that can be embolised Prevention Every effort should be made to prevent the formation of iatrogenic vascular abnormalities, such as pseudoaneurysm. This involves careful planning of the uterine incision during caesarean section, particularly when the cervix is fully dilated. Any dextro-rotation of the uterus should be corrected before making the incision and subsequent angle tears should be avoided by extending the incision upwards rather than downwards. Abu-Ghazza O, Hayes K, Chandraharan E, Belli A. Review: Vascular malformations in relation to obstetrics and gynaecology: diagnosis and treatment. The Obstetrician & Gynaecologist, 2010;12:87–93 Abu-Yousef MM, Wiese JA, Shamma AR. The ‘to-and-fro’ sign: duplex doppler evidence of femoral artery pseudoaneurysm. AJR Am J Roentgenol 1988;150:632. Asai S, Asada H, Furuva M, Ishimoto H, Tanaka M, Yoshimura Y. Pseudoaneurysm of the uterine artery after laparoscopic myomectomy. Fertil Steril, 2009 Mar;91(3):929. Cura M, Martinez N, Cura A, Dasaso TJ, Elmerhi F. AVMs of the uterus. Acta Radiol, 2009 Sep;50(7): Grivell RM, Reid KM, Mellor A. Uterine arteriovenous malformations: a review of the current literature. Obstet Gynaecol Surv, 2005 Nov;60(11): Takeda A, Kato K, Mori M, Sakai K, Mitsui T, Nakamura H. Late massive uterine hemorrhage caused by ruptured uterine artery pseudoaneurysm after laparoscopic- assisted myomectomy. J Minim Invasive Gynecol 2008;15:212–6. Uterine AVMs (continued) Figure 7 (taken during diastole) Figure 5 : A. True aneurysm B. False aneurysm