Arteriovenous Malformation of the Uterus: A Review and Update.

Abstract

Arteriovenous malformation of the uterus (AVMU) is a very rare and uncommon condition, because it has been documented that less than 100 cases of AVMU have been reported in the literature. AVMU is potentially a life-threatening condition with regard to the fact that some cases of AVMU could manifest with profuse bleeding from the uterus via the vagina. AVMU could either be congenital AVMU which is less common or acquired AVMU with pregnancy noted to have a role to play in the pathogenesis of AVMUs. The true incidence of AVMU is stated to be difficult to ascertain in view of the fact that some cases of bleeding that have been caused by AVMU do tend to conservative, medical management and many of these AVMUs could remain undiagnosed. The most common manifestations of AVMUs tend to be abnormal uterine bleeding that could be episodic, intermittent, continuous, mild or torrential which could lead to severe anaemia or shock. Some AVMUs could be found incidentally based upon radiology imaging for a different condition. Other symptoms of AVMUs do include: Metrorrhagia; Menorrhagia; Bleeding following a miscarriage; Bleeding following dilatation and curettage; Bleeding subsequently after hysterectomy; Bleeding associated with trophoblastic disease; Bleeding following caesarean section; Post-partum haemorrhage; Intermittent vaginal bleeding; Continuous vaginal bleeding; Post-menopausal bleeding; Acute abdominal pain with hemoperitoneum; Pallor; Dizziness; Weakness; Drowsiness; Being unwell following delivery of a baby; Bleeding following therapeutic abortion; Tachycardia; Supra-pubic pain at times; hypotension. Diagnosis of AVMU tends to be made based upon radiology imaging with utilization of ultrasound scan / Doppler scan of the uterus and pelvis, Contrast Computed Tomography scan, and Contrast Magnetic Resonance Imaging Scan, as well as by selective angiography which tends to be ensued by treatment with embolization of the feeding vessels to the AVMU. The treatment of AVMUs these days has ranged between conservative and medical management that includes hormones for small AVMUs, Hysterectomy, which tends to be a definitive treatment that removes the AVMU but does leave the individual not being able to maintain her future fertility, as well as selective angiography and super-selective embolization of the uterine arterial branches feeding the AVMU, which does tend to maintain the future fertility of the patients and which has the advantage of being undertaken under local anaesthesia. Questions that should be on the minds of clinicians include should doppler ultrasound scan of the uterus be undertaken with regard to all women who develop persistent vaginal bleeding pursuant to or during management of miscarriage, considering that there are very few interventional radiologists in many hospitals. This means that selective angiography plus super-selective embolization cannot be undertaken in district hospitals should all women who have suspected AVMU that have severe bleeding that may require surgical operation be referred to a tertiary hospital so that they could possibly benefit from the undertaking of selective angiography and embolization of their AVMUs instead of hysterectomy to enable them to maintain their future fertility? It is also important for clinicians to be made aware of the existence of AVMUs so that they could appreciate the risk factors as well as the clinical manifestations who should be suspected of possibly having AVMUs. Clinicians also need to learn about various conservative and expectant methods of treating AVMUs including hormonal treatment. Clinicians also need to appreciate the future implications for future fertility of women who have AVMUs. Possible treatment options that have not been utilized for the treatment of AVMUs include: (a) Radiology image-guided cryotherapy of AVMU, (b) Radiology image-guided radiofrequency ablation of AVMU, and (c) Radiology Image-guided Irreversible electroporation of AVMU. There is a global need for the training of more interventional radiologists all over the world including in the developing countries as well as some of the developed countries to that they can undertake embolization of AVMUs as well as they can provide various interventional radiology treatment options for various other conditions.