Femoral artery pseudoaneurysm is the most common complication of femoral access following diagnostic or therapeutic cardiac and peripheral angiographic procedures.1 A pseudoaneurysm or false aneurysm is a contained rupture in which blood leaks from an artery into the surrounding tissue (Figure 1). The pseudoaneurysm is contained by the surrounding tissue, which may include the artery's adventitia, femoral sheath, fat, or scar tissue. Pseudoaneurysms have many causes, including infection and trauma. This article focuses on femoral artery pseudoaneurysm following arterial access for angiographic procedures.
The number of diagnostic and therapeutic interventional procedures performed through femoral artery access has increased over the past decades, and more than 1 million cardiac catheterizations are performed in the United States annually.2 This does not include interventions for peripheral vascular disease. The reported incidence of pseudoaneurysm following femoral artery access varies. In one study, the incidence of pseudoaneurysm in more than 1,000 patients was 3.8%.3 A more recent study showed pseudoaneurysms in 2.9% of more than 500 patients.3 These studies performed routine duplex imaging on all patients following femoral access. Typically, routine imaging is not performed. Another study reported the incidence of pseudoaneurysm at 0.2% to 0.5% following diagnostic procedures and up to 8% following procedures with an intervention.4
Patient-related risk factors for pseudoaneurysm after femoral artery access include age over 75 years, hypertension, female sex, increased BMI, platelet count less than 200,000 cells/mm3, and arterial calcification. Procedure-related risks include emergency procedures (2.3% greater risk than for elective procedures), puncture site below the common femoral artery (superficial femoral artery or profunda femoris), and increasing sheath size (greater than 7 or 8 French).1,3,5 Procedural antiplatelet agents, anticoagulants, or needing continued anticoagulation postprocedure increase the patient's risk of forming a pseudoaneurysm.3
Pseudoaneurysms can be difficult to diagnose if the patient has a hematoma or groin discomfort; in patients with no groin discomfort and a normal physical examination, pseudoaneurysms may go undiagnosed.3 Consider pseudoaneurysm in patients presenting after femoral artery access with groin swelling or pain that is out of proportion to expected procedural-related discomfort. Patients may complain of a mass in the groin or feeling a “pop” associated with pain or a mass. A large pseudoaneurysm can compress the femoral nerve and cause neuropathy. Rarely, patients may develop claudication or limb ischemia secondary to embolization or arterial compression.1,5 Some patients may present with extensive bruising and skin changes or skin necrosis from large pseudoaneurysms that compromise the tissue.1 Patients with pseudoaneurysm rupture, the most serious complication, will present with severe groin and leg pain and can quickly become hemodynamically unstable due to arterial bleeding.1
Examining a patient with a tender groin may be difficult. Inspection may reveal ecchymosis, skin necrosis, or swelling of the groin or limb. The groin may be tender to palpation. The patient may have a pulsatile or nonpulsatile mass; presence of a pulsatile mass in the groin following femoral artery access is highly predictive of a pseudoaneurysm.3 The femoral pulse may or may not be palpable. Perform a complete vascular examination, including palpation of pulses distal to the pseudoaneurysm, and note any changes, especially the absence of pulses that were present before the procedure. A bruit or thrill may overlay the pseudoaneurysm.1
The diagnostic test of choice is duplex ultrasonography with B mode imaging, color flow imaging, and Doppler pulse wave analysis. Duplex imaging and pulse wave analysis can differentiate the pathology (hematoma, arteriovenous fistula, or pseudoaneurysm).3 Color flow is used to assess flow in the aneurysm. Color flow also can identify specific characteristics about the pseudoaneurysm that may help to guide treatment, such as the sac size, number of sacs, and neck length and width.3 Our practice has occasionally found pseudoaneurysms incidentally on a CT angiogram of the abdomen and pelvis.
The natural history of femoral access-related pseudoaneurysm has been studied extensively. Most of the research was done in the early 1990s. In one study by Toursarkissian, 86% of the patients selected for observation of the pseudoaneurysm underwent spontaneous thrombosis.6 Patients with a pseudoaneurysm less than 3 cm were observed and those with one greater than 3 cm underwent surgical repair.6 This study was done before use of dual antiplatelet therapy, which many authors believe adversely affects spontaneous thrombosis.4,7 Other studies documented a correlation between chronic anticoagulation and failure of the pseudoaneurysm to thrombose.7 A pseudoaneurysm with a neck length less than 0.9 cm took much longer to thrombose than ones with longer necks.3 Pseudoaneurysms with higher-volume flow (4.4 mL/min) were less likely to thrombose.3
The natural history suggests that most small (less than 2 cm) pseudoaneurysms spontaneously thrombose.1 Complications associated with pseudoaneurysm include rupture, infection, distal embolization, skin necrosis, and neuropathy from femoral nerve compression.1,5
Management includes observation, ultrasound-guided compression, ultrasound-guided thrombin injection (Figure 2), and surgery. Pseudoaneurysms that require more aggressive treatment include those that are expanding on serial duplex examinations, those causing significant pain, those that have failed to spontaneously thrombose after 1 month, those with a short neck, those greater than 2 cm, and pseudoaneurysms in patients on anticoagulation. Surgery was the mainstay of treatment before the 1990s. Ultrasound-guided compression was established in the early 1990s as an option instead of surgery. Now, ultrasound-guided thrombin injection has replaced conservative observation and ultrasound-guided compression because of its success rate (up to 97%) and low risk.8
Observation is still used for small pseudoaneurysms (those less than 2 cm).3,7 Patients considered for observation must have a small, stable pseudoaneurysm. Antiplatelet therapy, especially dual antiplatelet therapy, does not exclude observation for small pseudoaneurysms but may reduce the rate of spontaneous thrombosis (9% failure with no antiplatelet therapy compared with 44% on dual antiplatelet therapy).7 This failure rate in patients on dual antiplatelet therapy has significantly reduced observation as therapy. Patients under observation should undergo weekly duplex ultrasounds until pseudoaneurysm thrombosis. Weekly duplex ultrasounds can demonstrate if the pseudoaneurysm is growing. In a study by Stone and colleagues, the average increase of 1.1 cm was over 6.8 days in patients whose pseudoaneurysms did not thrombose, indicating more aggressive treatment was needed.7 Stone recommends duplex ultrasounds every 1 to 2 weeks.3 Patients must adhere to restrictions on lifting and bending, abstain from anticoagulation, monitor for pain increase, and demonstrate no growth of the pseudoaneurysm on scheduled serial duplex examinations. Patients should be considered for more aggressive treatment if the pseudoaneurysm is greater than 2 cm, has a short neck width (less than 4 mm), causes significant pain, is enlarging, occurs within 1 week of the index procedure, or if the patient is on anticoagulation.
In the 1990s, ultrasound-guided compression was used to treat pseudoaneurysms, replacing surgical procedures for many pseudoaneurysms and reporting an early success rate of 63% to 88%.5,8 This was before the use of dual antiplatelet therapy. Today, patients considered for ultrasound-guided compression have smaller pseudoaneurysms and have failed to thrombose spontaneously after a period of observation.3 Ultrasound is used to identify the pseudoaneurysm and the neck. The probe is used to apply compression to the pseudoaneurysm. Compression usually is held for cycles of 10 minutes, requiring an average of 37 minutes to achieve thrombosis.8
Ultrasound-guided compression is limited by patient discomfort; most patients require some degree of opioid analgesia for this procedure.3,8 The procedure is very taxing on the clinician applying pressure. Failure is associated with anticoagulation, body habitus, and size and depth of the pseudoaneurysm.1 After successful ultrasound-guided compression, the patient should lie flat for 2 to 4 hours. A repeat duplex is performed in 24 to 48 hours to insure that the pseudoaneurysm has not reopened. If compression is not successful, consider ultrasound-guided thrombin injection or surgery.
Ultrasound-guided thrombin injection has replaced ultrasound-guided compression in most practices. Injection has a success rate of 93% to 97%, compared with 63% to 88% for ultrasound-guided compression.3,8 Ultrasound-guided thrombin injection can be done in an inpatient or office setting. Local anesthesia is administered under ultrasound guidance and a sterile field. Dilute thrombin is then slowly injected into the pseudoaneurysm under duplex imaging to assess for thrombosis. After successful thrombosis, the patient is on bedrest for up to 12 hours, depending on the anatomy of the pseudoaneurysm and facility policy.1 Complications of ultrasound-guided thrombin injection are rare (1.2%), with the most common being distal embolization (0.5%).1
In some instances, surgical repair is still necessary.1,3,5 Patients with large hematomas resulting in skin necrosis or compressive symptoms such as neuropathy or ischemia, rapidly expanding pseudoaneurysms, and infected pseudoaneurysms are best treated with surgical repair.1,3 Surgical treatment carries a significant complication rate of 20%.1 Complications include bleeding, infection, seroma, neuralgia, prolonged hospital stay, and perioperative myocardial infarction.1,4 Be alert for worsening groin pain, fever, incision breakdown, erythema surrounding the incision, elevated white blood cell count, and drainage. Administer antibiotics; incisions that have broken down or dehisced may need to be opened and packed.
Although the incidence of pseudoaneurysm formation after femoral artery access is low, as more interventional procedures are performed, clinicians are more likely to see patients with this condition. Management has evolved over the past decades. The use of dual antiplatelet therapy has increased and can impair spontaneous thrombosis in pseudoaneurysms that would otherwise have only required observation.4,7 Many smaller pseudoaneurysms that would have been observed are now being treated with ultrasound-guided thrombin injection, letting patients resume normal activities earlier than if they had undergone observation.4,7,8 Using ultrasound to guide needle placement for femoral artery access has been shown to reduce postintervention complications with the greatest reduction in pseudoaneurysmal development.9
1. Webber GW, Jang J, Gustavson S, Olin JW. Contemporary management
2. Slicker K, Lane WG, Oyetayo OO, et al Daily cardiac catheterization procedural volume and complications at an academic medical center. Cardiovasc Diagn Ther
3. Stone PA, Campbell JE, AbuRahma AF. Femoral pseudoaneurysms after percutaneous access. J Vasc Surg
4. Schneider C, Malisius R, Küchler R, et al. A prospective study on ultrasound
-guided percutaneous thrombin injection
for treatment of iatrogenic post-catheterisation femoral pseudoaneurysms. Int J Cardiol
5. Morgan R, Belli AM. Current treatment methods for postcatheterization
pseudoaneurysms. J Vasc Interv Radiol
6. Toursarkissian B, Allen BT, Petrinec D, et al Spontaneous closure of selected iatrogenic pseudoaneurysms and arteriovenous fistulae. J Vasc Surg
7. Stone PA, Martinez M, Thompson SN, et al Ten-year experience of vascular surgeon management
of iatrogenic pseudoaneurysms: do anticoagulant and/or antiplatelet medications matter. Ann Vasc Surg
8. Taylor BS, Rhee RY, Muluk S, et al Thrombin injection
versus compression of femoral artery
pseudoaneurysms. J Vasc Surg
9. Lo RC, Fokkema MT, Curran T, et al Routine use of ultrasound
-guided access reduces access site-related complications after lower extremity percutaneous revascularization. J Vasc Surg
Keywords:Copyright © 2019 American Academy of Physician Assistants
femoral artery; pseudoaneurysm; management; postcatheterization; ultrasound; thrombin injection