Presentations

Abstract

Introduction:

Spontaneous rupture of an ovarian artery aneurysm is an exceedingly rare complication of multiple gestations. Although previously diagnosed and treated surgically, both diagnostic and interventional radiologic advances have allowed for a shift towards minimally invasive approaches, with high success rates and favorable outcomes.

Case Information:

On postpartum day 1, a 28-year-old gravida 3 para 3 developed a severe right-sided abdominal and back pain prior to becoming hypotensive. CT abd/pel at that time revealed a 20 x 12 x 26 cm retroperitoneal hematoma, after which she was transferred to our interventional radiology center for angiography and embolization. Access was obtained through the right femoral artery, and an infrarenal aortogram showed a hypertrophied and tortuous right ovarian artery with active extravasation at the midpoint. Transcatheter arterial embolization of the ruptured artery was performed with Ruby coils and Gelfoam, and the patient was discharged home on postop day 7. Two weeks later, the patient returned with recurrent pain, and CT imaging revealed a persistent retroperitoneal hematoma from a collateralized ipsilateral uterine artery, treated with CT-guided percutaneous drain placement. Subsequent visits showed a resolving hematoma, indicating a successful embolization.

Discussion:

Various hemodynamic changes have been implicated in the formation of aneurysms in pregnant women. During pregnancy, the enlargement of the uterus and dilatation of the pelvic blood vessels leads to an increased blood flow to the uterus. This peaks in the third trimester, as the heart rate, stroke volume, and overall cardiac output increases significantly to accommodate for the increased demands of the rapidly growing fetus. In addition, the changes in steroid hormones during pregnancy can lead to arterial changes that predispose patients to develop aneurysms in such high-flow states, such as intimal hyperplasia, thickening of the tunica media, fragmentation of reticular fibers, and loss of corrugation of elastic fibers. These changes should normally resolve in the postpartum period; however, it is thought that aberrant involution may lead to a predisposition for aneurysmal formation in subsequent pregnancies. This repeated cycle of hemodynamic and hormonal changes that occur in multigravida women are likely the cause of the formation of aneurysms, with hypertension serving as a common risk factor for aneurysmal rupture.

Spontaneous rupture of ovarian artery aneurysms can be a life-threatening event, that can rapidly progress to hemodynamic collapse. The most commonly presenting symptom of a ruptured aneurysm is acute flank/abdominal pain; however, as this pain is nonspecific, other differentials (such as acute abdomen and ureteral calculi, or uterine rupture and placental abruption in pregnant patients) need to be ruled out before a ruptured aneurysms should be considered. Previously, the diagnosis was usually confirmed via exploratory laparotomy; however, contrast-enhanced CT angiography has since come in favor, due to being highly effective and less invasive for confirmation of the pre-operative diagnosis. As radiographic confirmation has come into favor as the preferred modality for diagnosis, similar shifts have been seen toward the interventional radiologic approach for treatment. Of the 18 reported cases of ovarian artery aneurysms, 61% were treated with a transcatheter arterial embolization, most commonly with microcoils and gelatin sponge particles (such as gelfoam), with an 82% success rate. However, as this is still such an exceedingly rare condition, the diagnostic and treatment protocol should continue to be adjusted as information from future cases arises. As shown in our patient, collateralization from the uterine artery could lead to a persistent hematoma even weeks after the initial ovarian artery embolization. As such, consideration should be given to angiography of the ipsilateral uterine arteries in future cases, ensuring that all the blood vessels supplying the aneurysm have been identified and properly embolized. By doing so, the hope is to ensure a greater overall success rate of transcatheter arterial embolizations of ruptured ovarian aneurysms, thereby decreasing subsequent repeat hospital visits.

Conclusion:

Spontaneous rupture of an ovarian artery aneurysm is an exceedingly rare yet life-threatening complication of multiple gestations. With advances in diagnostic and interventional radiology, angiography and transcatheter arterial embolization have shown to be highly successful in both the diagnosis and treatment of these aneurysms. However, as information arises from future cases, consideration should be given to adjusting the approach to both diagnosis and treatment, ensuring higher treatment success rates and favorable outcomes.