Enhanced myometrial vascularity: what, where and when to treat.

Enhanced myometrial vascularity (EMV) is defined as focal myometrial hypervascularity at the former placental implantation site identified after a recent pregnancy. Spectral Doppler imaging shows characteristic high velocity, low resistance flow. Proposed mechanisms underlying prolonged EMV include delayed involution of remodeled uterine arteries and persistent trophoblastic activity with associated neoangiogenesis. EMV may reflect normal involution or subinvolution of the placental site or may be associated with retained products of conception. While often self-limited in asymptomatic patients, EMV in the setting of abnormal uterine bleeding warrants further evaluation and tailored management. Terminological ambiguity persists between EMV and acquired arteriovenous malformation (AVM) or fistula (AVF). Although Doppler findings may suggest arteriovenous shunting, cross-sectional imaging alone cannot reliably distinguish these entities, and catheter angiography remains the reference standard when definitive characterization is required. Importantly, many cases labeled as "acquired AVM" in the postpregnancy setting likely represent EMV related to persistent uteroplacental circulation or subinvolution rather than true vascular malformations. This distinction is clinically important, as true high-flow lesions, though less common, carry a risk of significant hemorrhage and may require uterine artery embolization. EMV may also be seen following intrauterine ectopic pregnancies, most commonly those implanted within a Cesarean scar. Several conditions may mimic EMV, including adenomyosis, pseudoaneurysm, gestational trophoblastic disease, fibroids, polyps, endometrial neoplasm and infection. Management is individualized based on clinical status, imaging findings, and associated conditions. Accurate recognition of EMV and use of this specific terminology as well as differentiation from mimics, is essential to guide appropriate care and avoid unnecessary interventions.