Uterine Artery Embolization


What is a uterine fibroid?

A uterine fibroid, also known as a leiomyoma, is a non-cancerous growth that develops in the uterine wall. In some cases, depending on their size and location, uterine fibroids may cause pelvic pain and excessive bleeding.


What is a uterine artery embolization (UAE)?

Uterine artery embolization, or uterine fibroid embolization (UFE), has emerged as a safe and effective non-surgical treatment for management of symptomatic uterine leiomyomas. A catheter is placed in each of the two uterine arteries and small particles are injected to block the arterial branches that supply blood to the fibroids. The fibroid tissue dies, the masses shrink, and in most cases symptoms are relieved. Uterine fibroid embolization, done under local anesthesia, is much less invasive than open surgery done to remove uterine fibroids. Indications for uterine artery embolization include menorrhagia (vaginal bleeding), pelvic pain or pressure, and other "bulk" symptoms such as low-back pain, urinary frequency, and constipation.


How do I prepare for a uterine artery embolization?

A woman considering uterine artery embolization needs a gynecological work-up to make sure that fibroid tumors are the actual cause of her symptoms. Imaging of the uterus by magnetic resonance imaging (MRI) or ultrasonography is performed to fully assess the size, number and location of the fibroids. Occasionally your gynecologist may want to take a direct look by performing laparoscopy. If bleeding is a major symptom, a biopsy of the endometrium the -inner lining of the uterus- may be done to rule out cancer.


Pre-Procedure Testing

• A negative PAP smear within the last year to exclude cancer of the cervix.
• A cervical culture is necessary to exclude infection for those with a history of pelvic inflammatory disease (PID) or current vaginal discharge. UFE must not be performed until any infection is eradicated.
• MRI and ultrasound of the pelvis is performed to more accurately define the size, location, and extent of fibroids.
• Bloodwork to test blood clotting factors to minimize the risk of bleeding complications.


How is a uterine artery embolization performed?

Several days prior to the procedure you will be given instructions from the Interventional Radiologist's office staff. You will need to have blood drawn at the hospital or a local clinic for testing. The staff will instruct you on how to prepare for the procedure including modification of your medications if necessary.

The procedure is performed in the interventional radiology suite. First, the nurse will give you a sedative through the intravenous line, which will be placed in your arm. You will feel relaxed and sleepy, but you will be awake throughout the procedure. The Interventional Radiologist will numb an area of your groin with a local anesthetic. Using a very small incision, he will then place a small, thin tube called a catheter into the femoral artery which is a large artery in the groin. The Interventional Radiologist will then advance the catheter over the aortic bifurcation into the iliac artery on the opposite side and into the uterine artery artery. An angiogram, which an x-ray procedure that studies the arteries or veins, will then be performed to determine the location of the fibroids. Because arteries and veins cannot be seen under x-ray, contrast media (x-ray dye) is used to "visualize" the vessels under x-ray.

Embolic materials will then be advanced through the catheter into the uterine artery to block the blood flow to the fibroids. Once the uterine artery is occluded, the catheter will be repositioned into the uterine artery on the opposite side and the embolization procedure is repeated. Occasionally, catheters placed in both femoral arteries are necessary to complete the embolization procedure when the anatomy is difficult. The catheter is then removed and the Interventional Radiologist will apply pressure at the groin site for about 20 minutes to prevent bleeding.

The embolic materials used may vary. The most common materials include polyvinyl alcohol (PVA) particles, Embospheres®, and Gelfoam®. PVA looks like finely ground, white grains of sand. These particles become wedged in the blood vessels when injected through the catheters. Embospheres® are clear acrylic microspheres that are compressible, allowing easy passage through catheters and into the vessels. Gelfoam® is a gelatin sponge that is cut into small pieces and injected through the catheter into the vessels.

Most patients are discharged within 24 hours after the procedure; however, hospitalization for up to 48 hours is occasionally required for management of postoperative pain. The majority of patients are able to return to normal activities within one week.


Procedure Results

Technical success rates of uterine artery embolization for management of symptomatic subserosal, intramural, and/or submucosal leiomyomas range from 95-100%. Improvement of symptoms occurs in 80-94% of cases. Up to 10% of patients subsequently require surgery due to treatment failure. A nationwide registry has been constructed for the accumulation of procedural and follow-up data so that success and complication rates can be accurately determined and long-term issues about the durability of UFE and possible side effects can be addressed.


Pregnancy

Patients have become pregnant and carried normal pregnancies to term following uterine fibroid embolization. These reports, however, are anecdotal, and the effect of uterine fibroid embolization on fertility has not been adequately studied. Until prospective studies are completed, women should be informed that uterine fibroid embolization may have a negative impact on fertility. Myomectomy remains the standard care for women who require treatment for symptomatic fibroids and who desire to become pregnant. When myomectomy is contraindictated, then uterine fibroid embolization may be an acceptable alternative for these women.

There are several ways that pregnancies may be affected by uterine artery embolization. During the embolization, flow in the uterine arteries is temporarily decreased. It is uncertain what effect this will have on the ability to become pregnant or to carry a pregnancy to term. In most cases, the arteries reopen to the normal parts of the uterus over time. As the fibroids die and begin to shrink, in some cases this may weaken the wall of the uterus. This appears to be more likely with large fibroids that span the entire wall of the uterus. However, fibroids compress the normal uterine tissue adjacent to them and as they shrink, the normal tissue may be restored to a more normal configuration. For any patient, it is difficult to predict whether the uterus will be weakened to the point where there might be a problem during delivery of a baby. Patients who do become pregnant should have an ultrasound to evaluate the uterine wall.


Complications

Patients tolerate uterine fibroid embolization well; however moderate to severe pain and cramping is expected following the procedure. Significant post-embolization syndrome occurs in up to 20% of patients undergoing embolotherapy. These symptoms include fever, which may or may not be accompanied by anorexia, nausea, and vomiting. They usually resolve within three days. Unusual complications include spontaneous expulsion of fibroid tumor, infection, and ischemia.


Patient Discharge and Follow-up Instructions

Before discharge from the hospital, the nurse will review the discharge instructions with you and give you a copy to take home. Instructions include:

• Take pain medications as directed. Report pain that is not controlled with medications.
• Rest remainder of the day
• Limit activity for next 2 days
• After 3 days gradually increase daily activity to normal
• You may drive 24 hours after discharge
• You may resume your normal diet
• No heavy lifting for 7 days
• You may need to wear a sanitary pad for light to moderate vagina discharge for 7 – 10 days
• No baths for 10 days. You may shower
• Nothing in vagina for 3 weeks (no intercourse)
• Schedule follow-up appointments
• See the Interventional Radiologist within 2 weeks
• See your OB-GYN physician within 3 months
• Schedule a follow-up ultrasound/MRI study at 3 and 6 months
• Report sudden onset of pain or cramping
• Report bright red vaginal bleeding that continues for more than 24 hours or saturates more than 3 pads within 8 hours
• Report foul vaginal order or drainage
• Report chills and/or fever greater than 101°