DIAGNOSIS AQUIRED AVM byCOLLOR DOPPLER ULTRASOUND(Case Report)

Syaiful Kurniasari, YusrawatiFetomaternal Obgyn Division Medical Faculty of Andalas UniversityDR. M. Djamil Hospital Indonesia

AbstractObjective : Reported a case Arterivenous Malformation on previous caesarean sectionDesign : Case reportPlace : Fetomaternal Obgyn division, Medical Faculty of Andalas University DR. M. Djamil Hospital

BackgroundArteriovenous Malformations (AVM) is an abnormal relationship between the arteries and veins, where there is no capillary system between the arteries and veins. Etiology can be congenital or acquired AVM. Because of lack of reporting, we do not know the incident of these case. Gold standard to diagnosis of these case is perform angiography, to identify blood vessels supplying the disordered regions. In addition, the use of color sonography Doppler as a non invasive examination methods are good

Case:Reported one case, Mrs. E 25 years old with diagnose P2L1 with AUB ec AVM + mild anemia (Hb 9,7 g/dl). From ultrasound imaging, there is a sonolucen area in incision caesarean section field 1x1 cm. With color Doppler ultrasound, the area from new-vascularization (AVM). Two days after treatment, there is a vaginal bleeding massive and recurrent. Total hysterectomy was perform. We found a new-vascularization and opened inside uterine (AVM) who come from incision caesarean section field.

Conclusion:Diagnosis of AVM can be detected on color Doppler examination.

Key Word:AVM, Color Doppler, Caesarean Section

ACQUIRED AVM DIAGNOSTIC BY COLOR DOPPLER ULTRASOUND

PrefaceUterine arterio-venous malformation (AVM) is a case that rarely causing sudden and massive vaginal bleeding. Although rare, secondary arterio-venous malformation can appears after sectio caesarea.(1,2) Uterine arterio-venous malformation was firstly described by Dubreuil and Loubat in 1926. The incidents of the case werent accurately known because of the scarce report of the case. (3,4)Patient with AVM usually complaints menorrhagia or metrorrhagia after miscarriage, uterine surgery including sectio caesarea, or curetage. Bleeding manifestation can be either few or profuse. In severe cases, the malformation can cause dyspneu and heart failure. (5)

Literature ReviewDefinitionArteriovenous malformation (AVM) is an abnormal connection between artery and vein, which has no capillary system between them. On histology examination, a local proliferation of the artery and vein is found, with fistulae which connects it(interconnecting fistulae). Also, the muscular layer of the vessel is thin. (3,6)

Picture 1. Arteriovenous Malformation (American Heart Association,2013)

EtiologyUterine arterio-venous malformation can be congenital or acquired. In congenital uterine arterio-venous malformation, malformation can be happened because of the failure of artery and vein angiogenesis alongside with the existence of multiple anastomosis, with disorder of the muscle and skin around the area. In acquired uterine arterio-venous malformation, malformation can develops from trauma on the uterine, such as sectio caesarea, curetage, and the insertion if intrauterine device (IUD). (7,8)

Clinical ManifestationGenerally, the symptoms caused by this disorder which need special attention by clinicians are: (9) Severe secondary postpartum hemorrhage Episodes of recurrent secondary postpartum hemorrhage History of blood transfusion to overcome anemia caused by postpartum hemorrhage Painless bleeding History of sectio caesarea, especially in emergency cases History of failure of medical therapy against bleeding Other cause of bleeding have been excluded

DiagnosisUterine arterio-venous malformation usually is not easy to diagnose. Not only because of the scarce amount of the cases but also because the symptoms were similar with another pathological conditions, such as bleeding on placental bed, residue of conception, and gestational trophoblas disease. Back then, the diagnosis of this disorder was taken after pathological examination on uterus after hysterectomy was done. (10,11)Angiography is the gold standard on diagnosing the existence of arterio-venous malformation. This invasive procedure is not only confirming diagnosis but also identify the blood vessel supplying the area with disorder, making it easy to do embolization. But the use of Doppler color sonography also provides a good non-invasive examination method. (5,8,12)

Picture 2. Angiography result in Arteriovenous malformation (Dadhwal,2007)

Picture 3. Abdominal Ultrasound finding in AVM. There is a malformation from left arterial uterine (Hashim et al,2013)On sonography examination, uterine arterio-venous malformation will show a hypoechoic area between myometrium and endometrium layers. With the use of color Doppler sonography, it will shows a mosaic appearance inside that hypoechoic area showing multiple turbulent pattern of blood current (shown by red and blue color which appears alternately). On spectrum analysis by sonography Doppler, it will shows the fast blood current with low resistance. (3,8,12)The examination of anatomical pathology will shows either a thick or thin walled vessels, without capillary bed.

Picture 4. Thick and thin walled vessels without intervening capillary bed (Robbins Pathologic Basis of Disease, 6th ed. 1999, P.1313)

Picture 5. Histology of the pulmonary arteriovenous malformation with a vessel transition from the arterial side (black arrows) to the venous side (blue arrowheads) H.E. staining, magnification200. RS rupture site (Ishikawa et al, 2010)

PreventionCongenital uterine arteriovenous malformation (AVM) is not a preventable disease, however acquired AVM is almost always iatrogenic in etiology. The majority of woman who suffer from acquired uterine AVM have history of previous obstetric or gynecologic surgery, in which emergency cesarean section at second stage of labor is the most common, and others also occur in curettage and gynecologic surgery on the uterus.Failure to secure the corner of uterine wound co-occured with rupture of uterine artery may result in AVM. Therefore, it is imperative to make sure that each corner of uterine wound is well sutured. AVM lesion most commonly occurred on the left side of uterus.

Management

Figure 4. Algorithm of Arteriovenous Malformation Management with hemorrhage (Eling, et al, 2012)Embolization therapy in uterine arteriovenous malformation was first introduced in 1986. This procedure was performed by percutaneous catheterization into femoral artery. The most commonly used agents for embolization include alcohol polyvinyl, gelfoam, stainless steel coils, emboshere, and onyx.Embolization is a minimal invasive procedure and can be performed under local anesthesia. In addition, uterus can be conserved and the source of hemorrhage can be accurately identified. If the source of hemorrhage is unidentifiable, empiric embolization to uterine artery or anterior internal iliac artery is an option. The success rate of such embolization in managing uterine AVM is quite high. Nevertheless, should that procedure fail, hysterectomy will be a preferable choice.

Picture 5. Angiography on uterine arterial embolization (Dadhwal,2007)

Meng et al described an alternative therapy in uterine AVM cases in which methotrexate (MTX) was given. In their study, they found that MTX had an impact on muscular layer of blood vessels by ceasing the cellular proliferation as well as inducing apoptosis. This mechanism occurred because MTX is a folic acid antagonist that inhibit DNA synthesis by eliciting acute intracellular deficiency. Deoxyuridine monophosphate is a folic acid coenzyme that is capable of inhibiting endocytic pathway which was activated by such folic acid receptor.

CASE REPORTWe reported a case of vaginal bleeding attributable to uterine aneurism complicated with chronic anemia. History taking disclosed that patient had cesarean section 6 months ago. A month following cesarean section, fresh red blood started to ooze from her vagina. This complain occurred unrelentingly up to now. The abdomen appeared to be normal from gynecologic examination. Vaginal speculum examination revealed a dark red blood pooling in the posterior fornix and passing through a closed cervical canal. Manual vaginal examination found no abnormality. Laboratory investigation showed a mild anemia (Hemoglobin: 9.7 g/dl). Ultrasound displayed a sonolucent area measuring +1x1cm at the old incision site which turned out to originate from vascularization (AVM) according to blood flow examination with Doppler ultrasound. Initial plan was to administer methotrexate therapy.

Before methotrexate therapy was initiated, the patient experienced a massive recurrent bleeding that her hemoglobin decreased significantly resulting in shock, and we then decided to perform hysterectomy. Intraoperatively the uterus was seen with a size of 7x5x2 cm. After the uterus was cut open, there was a blood vessel exposed to uterine cavity (AVM) at the previous incision site (lower uterine segment). The uterus specimen was sent for anatomic pathology examination.

Caesarean incision (caesarean scar)

Portio

AVM

Diagnosis/ Post total hysterectomy on indication of AVMThe result of anatomic pathology examination: Macroscopic: a cut of cervical tissue with a size of 3x3x2cm with a dense white surface. Microscopic: Cervical tissue was visualized with stratified squamous epthelium containing koilocyte and loose connective tissue containing endocervical glands which were lined by cuboid epithelium. The tissue was highly vascular.

Thick and thin walled vessels without intervening capillary bed.

Arterovenous malformation with a vessel transition from the arterial side (black arrows) to the venous side (blue arrow)DISCUSSIONDiagnosis of AVM was established with the anamnesis that revealed a complaint of painless recurrent massive postpartum bleeding. Ultrasound displayed a sonolucent area measuring 1x1cm at the old incision site (lower uterine segment). Blood flow examination with Doppler ultrasound was performed and found that the sonolucent area originated from vascularization (AVM). Even though angiography is the gold standard in diagnosing arteriovenous malformation, the use of color Doppler ultrasound also provides a good non-invasive examination method. On sonography, AVM is visualized as hypoechoid area between myometrium and endometrium. Color Doppler ultrasound will show a mosaic area in hypoechoic region with multiple/turbulent blood flow pattern (indicated by interchanging color of red and blue). Ultrasound finding in this patient was confirmed by the presence of a blood vessel which was exposed to uterine cavity at the previous incision site (lower uterine segment).In acquired AVM, malformation results from uterine trauma, such as in cesarean section, curettage and insertion of intrauterine device (IUD). The possible cause of AVM in in this case is the failure to secure the corner of the uterine wound when performing cesarean section. In patient with stable hemodynamic state, management of AVM with expectative therapy can be performed, though It may require intensive monitoring and longer admission time. Nevertheless, hysterectomy is preferred in emergency setting.

CONCLUSIONDiagnosis of AVM can be made with the examination of color Doppler ultrasound.

SUGGESTIONColor Doppler ultrasound examination in recurrent postpartum bleeding with previous cesarean section can identify the possibility of uterine AVM.

REFERENSI1. Patel, Sapna, Potti, Sushma and Jaspan, David. 2009. Embolization of Uterine Arteriovenous Malformation for Treatment of Menorrhagia. Arch Gynecol Obstet. Philadelphia: Springer-Verlag, 2009, Vol. 279, pp. 229-232.2. Jeve, Yadava, Janjua, Aisha and Qureshi, Najum. 2013. Secondary Post-Partum Hemorrhage Due to Secondary Uterine Arterio-venous Malformation following Caesarean Section. Journal of Pharmaceutical and Biomedical Sciences. Birmingham: Birmingham Women's NHS Foundation Trust, 2013, Vol. 28, 12, pp. 643-645.3. Kelly, S. M., Belli, A. M. and Campbell, S. 2003. Arteriovenous Malformation of The Uterus Associated with Secondary Postpartum Hemorrhage. Ultrasound Obstet Gynecol. London: John Wiley & Sons, Ltd, 2003.4. Castillo, Monette S., Borge, Marc A. and Pierce, Kenneth L. 2007. Embolization of a Traumatic Uterine Arteriovenous Malformation. Seminars in Interventional Radiology. New York: Thieme Medical Publisher, 2007, Vol. 24, 3, pp. 296-299.5. Timmerman, D., et al. 2003. Color Doppler Imaging is a Valuable Tool for the Diagnosis and Management of Uterine Vascular Malformations. Ultrasound Obstet Gynecol. s.l.: John Wiley & Sons, Ltd., 2003, 21, pp. 570-577.6. Poder, Liina. 2008. Ultrasound Evaluation of the Uterus. [book auth.] Peter W. Callen. Ultrasonography in Obstetrics and Gynecology. 5th. Philapdelphia: Elsevier, Inc., 2008, Vol. II, 27, pp. 919-941.7. Mohamed, SI, Abdullah, BJJ and Omar, SZ. 2005. Postpartum Haemorrhage. Biomedical Imaging and Interventional Journal. Kuala Lumpur: Department of Biomedical Imaging (Radiology), University of Malaya, 2005.8. Syla, B. H., Fetiu, S. S. and Tafarshiku, S. S. 2011. Transabdominal Two- and Three-Dimensional Color Doppler Imaging of A Uterine Arteriovenous Malformation. Ultrasound Obstet Gynecol. s.l.: John Wiley & Sons, Ltd., 2011, 37, pp. 376-378.9. Hayes, K. 2012. Vascular Malformations as a Cause of Postpartum Hemorrhage. A Comprehensive Textbook of Postpartum Hemorrhage. 2nd. s.l.: Sapiens Publishing, Ltd., 2012, Vol. 4, 26, pp. 218-224.10. Mungen, E., et al. 1997. Color Doppler Sonographic Features of Uterine Arteriovenous Malformations: Report of Two Cases. Ultrasound in Obstetics and Gynecology. 1997, Vol. 10, pp. 215-219.11. Eling, Rebeka, Kent, Alison and Robertson, Meiri. 2012. Pregnancy after Uterine Arterio-Venous Malformation - Case Series and Literature Review. Australasian Journal of Ultrasound in Medicine. Canberra: Minnis Journals Pty Ltd., 2012, Vol. 15, 3, pp. 87-97.12. Hashim, Hilwati and Nawawi, Ouzreiah. 2013. Uterine Arteriovenous Malformation. Malays J Med Sci. s.l.: Penerbit Universiti Sains Malaysia, 2013, Vol. 20, 2, pp. 76-80.13. Dadhwal, Vatsla, et al. 2007. Uterine Artery Pseudoaneurysm with AV Malformation: A Rare Cause of Secondary Post Partum Hemorrhage. All India Institute of Medical Sciences. Ansari Nagar: Department of Obstetrics and Gynecology and Radiology, 2007, Vol. 9, 3, pp. 142-144.14. Wendel, Mark, et al. 2013. Transcatheter Arterial Embolization of A Uterine Artery Pseudoaneurysm with Onyx Following D&C for Uterine Bleeding. Radiology Case Reports. 2013, Vol. 8, 2.15. Meng, Leil, et al. 2004. The Effects of Methotrexate on Vascular Smooth Muscle Cells Proliferation, Migration and Apoptosis. Chinese Pharmalogical Bulletin. 2004, 11.16. Skubisz, Monika M. and Tong, Stephen. 2012. The Evolution ofMethotrexate as a Treatment for Ectopic Pregnancy and Gestational Trophoblastic Neoplasia: A Review. International Scholarly Research Network Obstetrics and Gynecology. 2012.