This article is part of a three part series on pseudoaneurysms. Part 1 describes what a pseudoaneurysm is, what causes it, and how to diagnose it. Part 2, the current article, discusses the four most common treatment options. And Part 3 provides a summary of pseudoanerysms and a complete list of references used in this series of articles.
Treatment Options for Pseudoaneurysms (False Aneurysms)
Before a pseudoaneurysm can be treated, it must be accurately diagnosed. The imaging methods of diagnosis, including doppler ultrasound, arteriography, CT angiography, and MR angiography are discussed in the previous article. A clinician should be cautious in examining a mass that may be a pseudoaneurysm. In many cases, a clinician may think that a warm, painful mass is an abscess (infection), and the clinician will "I&D" (incise and drain) the mass. If, however, the mass is instead a pseudoaneurysm, which maintains a connection with a nearby artery, then the patient could bleed profusely. A suspician for pseudoaneurysms and an accurate diagnosis is important.
Surgical repair: If the artery supplying the pseudoaneurysm is badly damaged, or if blood is not flowing well through the artery to distal muscles and tissues, then the patient may need surgery to repair the artery and restore blood flow. One option to accomplish this is to cut off blood flow to the pseudoaneurysm (by "proximal and distal ligation"), and then reroute blood around this damaged segment of the artery. The blood can be rerouted using a piece of the patient's vein or by using a synthetic graft. The vein or graft is connected to the artery before and after the pseudoaneurysm, and blood then flows around this damaged segment. Surgical repair of pseudoaneurysms is preferred if the patient needs reconstruction of damaged arteries to restore adequate blood flow.
Endovascular procedures: Another less invasive option repair pseudoaneurysms is to use an "endovascular" approach, in which thin instruments are inserted into an artery and threaded through the arterial system to the section containing the pseudoaneurysm. A "covered stent," which looks like a thin tube, can be inserted within the artery. Since pseudoaneurysms expand because they receive blood from the artery, the covered stent (tube) placed within the artery will block the hole that allows blood to reach the pseudoaneurysm. Blood can still flow through the covered stent so it can reach the muscles and tissues, but it is then blocked from leaking through the arterial wall into the pseudoaneurysm.
This method is often preferred because a large surgery is not needed; instead, the covered stent can be inserted endovascularly, for example through the femoral artery in the patient's groin.
Ultrasound-guided compression of the pseudoaneurysm: Since the pseudoaneurysm exists and expands because it receives blood from a leakage from a small hole in an artery, it is expected that the pseudoaneurysm will shrink and clot off if the connection with the supplying artery is removed. One way to do this is by "ultrasound-guided compression." An ultrasound probe is used to find the pseudoaneurysm and its connection with the artery. The doctor pushes down with the ultrasound probe and compresses this connection with the artery. Within 10 to 20 minutes of compression, the connection should clot off and no longer supply the pseudoaneurysm with blood.
This method is only 30-62% effective in patients on anticoagulation (heparin, warfarin (Coumadin), etc.), since anticoagulants prevent the connection from the artery to the pseudoaneurysm from clotting off. However, the procedure is 74-95% effective in patients not on anticoagulation. It is most effective for small pseudoaneurysms, less than 3 cm. This procedure is not used much anymore, since pushing with the ultrasound probe for 10-20 minutes is often painful, and covered stent placement and thrombin injection, discussed below, are often more effective. It is also not as effective in obese patients or for deep pseudoaneurysms, in which it is more difficult to compress the connection with the artery.
Ultrasound-guided thrombin injection: An ultrasound probe is used to localize the pseudoaneurysm. Thrombin, a chemical that stimulates clotting, is injected into the pseudoaneurysm. The pseudoaneurysm clots off and is no longer at risk of expanding or rupturing. Also, normal blood flow within the artery is maintained.
This procedure is very successful and relatively inexpensive. However, it cannot be used if the patient has an "arteriovenous fistula," which is an abnormal connection between an artery and a vein. This is because the injected thrombin, instead of staying within what was thought to be a pseudoaneurysm cavity, could then leak into the venous system and cause clots throughout the body. 10% of patients with a pseudoaneurysm also have an arteriovenous fistula, though this can be detected with imaging techniques (discussed in the first article).
A summary of pseudoaneurysms and listing of references is found in Part 3. See Part 1 for the description, causes, and diagnosis of pseudoaneurysms.
David Henry - David Henry, M.D., is a general surgery resident in Michigan and a graduate of medical school in Philadelphia. In five years, David plans ...
Join the Conversation