Spontaneous Rupture of the Superficial Femoral Artery Treated via an Endovascular Approach

Abstract

Isolated spontaneous rupture of the superficial femoral artery is very uncommon. To our knowledge, only 5 other cases have been reported in the medical literature.

Herein, we report the case of an 86-year-old woman who was admitted to our hospital with a 4-day history of progressive swelling of the left thigh. The presence of a pulsating mass with paresthesia of the lower limb and anemia suggested a hematoma of the thigh. A computed tomographic scan revealed a 4-cm-diameter pseudoaneurysm of the left superficial femoral artery and a large hematoma of the medial muscle compartment. A nitinol-polytetrafluoroethylene VIABAHN® self-expanding stent-graft (5-mm diameter × 50-mm length) was placed beyond the arterial lesion, and a fasciotomy of the thigh was performed. On the 10th postoperative day, the patient was discharged from the hospital in good condition.

In cases of spontaneous swelling of the thigh in the absence of trauma or other apparent causes, spontaneous rupture of the superficial femoral artery should be suspected. Surgical treatment is preferable in young patients. In patients who are elderly or in poor condition, endovascular therapy is preferable when there is diffuse atherosclerosis of the artery.

Isolated spontaneous rupture of the superficial femoral artery is extremely rare; to our knowledge, only 5 other cases have been reported in the medical literature.^1–3 Herein, we report a case of spontaneous rupture of the superficial femoral artery with consequent pseudoaneurysm in an elderly woman who had no history of recent trauma.

Case Report

In April 2005, an 86-year-old woman was admitted to our department with a 4-day history of progressive swelling of the left thigh. There was no history of trauma. The patient presented with no signs of shock or infection. The clinical examination revealed a pulsating mass and paresthesia of the lower limb without motor impairment. The laboratory findings included a hemoglobin level of 8.7 g/dL, without alteration of the coagulation profile or the platelet count. Ultrasonographic duplex scanning showed a massive hematoma of the muscles and normal patency of the femoral artery and veins. A computed tomographic scan revealed an extensive hematoma of the thigh muscles from the iliac crest to the knee. Due to the progressive decrease of the patient's hemoglobin level to 7.0 g/dL and initial signs of hemodynamic shock, magnetic resonance imaging was performed. This investigation revealed a 4-cm-diame-ter pseudoaneurysm of the left superficial femoral artery and a large hematoma of the medial muscle compartment (Fig. 1).

Fig. 1 Magnetic resonance imaging shows a pseudoaneurysm of the left superficial femoral artery.

Arteriography revealed diffuse calcification of all of the femoral arteries and rupture of the middle portion of the left superficial femoral artery consequent to a pseudoaneurysm (Fig. 2). No lesions were detected elsewhere.

Fig. 2 Intraoperative arteriography shows the arterial lesion (arrow).

Due to the arterial calcification and the patient's age, endovascular treatment was undertaken. A 5F introducer sheath was exchanged for a 45-cm, 8F operative sheath in order to cross the iliac bifurcation, and systemic heparin (100 U/kg) was administered. A hydrophilic guidewire was pushed distally to pass the arterial wall lesion. After placement of a stiff guidewire over the catheter, we placed a nitinol-polytetraflu-oroethylene VIABAHN® self-expanding stent-graft (5-mm diameter × 50-mm length, W.L. Gore & Associates, Inc.; Flagstaff, Ariz) (Figs. 3 and 4). We preferred a small stent-graft due to the small defect and to the presence of calcification, which carried a high risk of iatrogenic injury to the artery. After its deployment, the stent-graft was dilated and modeled by use of a 5-mm balloon.

Fig. 3 The VIABAHN® stent-graft, in different sizes.

Fig. 4 Three-dimensional view of a VIABAHN® stent-graft.

Angiographic examination showed complete exclusion of the pseudoaneurysm (Fig. 5). A fasciotomy of the thigh was performed to avoid compression of the deep venous system, nerves, and the stent-graft. The patient's condition was then monitored in the intensive care unit for 24 hours, during which time her lost blood was restored by infusion, and coagulation values were normalized.

Fig. 5 Postoperative arteriography shows normal patency of the repaired arterial tract (arrow).

The patient's postoperative period was complicated by persistent fever without white blood cell elevation. On the 10th postoperative day, the patient was discharged from the hospital in good condition.

Discussion

Pseudoaneurysms of the femoral arteries are rare and are usually due to penetrating or blunt trauma. They may occur in association with bone fractures, bone tumors, or orthopedic procedures.^4–6 Spontaneous rupture of the femoral artery is extremely uncommon; to our knowledge, only 5 other cases have been reported. The cause of spontaneous rupture is unclear: in young patients, some investigators have presumed connective tissue disorders or congenital arterial abnormalities to be t he c au se.^7,8 In these cases, lesions of the arterial wall and the consequent pseudoaneurysms after low-degree trauma or a sports activity can lead to acute hip and trunk torsion.⁹ In elderly persons, atherosclerosis has been considered a cause. In fact, at herosclerosis and arterial wall weakness can result in easy rupture of the plaque and the resultant development of pseudoaneurysms. In our patient, we noted diffuse and severe atherosclerosis of the femoral arteries, which we considered the likely cause of the spontaneous rupture of the superficial femoral artery.

Although ultrasonic duplex scanning can be a sensitive, specific, and accurate investigative technique, the presence of a massive hematoma—as in our patient—can lead to an incomplete diagnosis.¹⁰ Magnetic resonance angiography and spiral computed tomographic angiography can aid in precise delineation of the site of rupture and the dimensions of the pseudoaneurysm. In addition, these techniques enable detection of bilateral femoropopliteal or arterial muscular branches that are involved in the pseudoaneurysmal degeneration. In particular, angiography can be helpful when therapeutic embolization of the femoral artery branches becomes necessary.¹¹

In some patients who experience insubstantial bleeding without vein or nerve compression, conservative treatment may be proposed.¹² Conversely, when massive bleeding has occurred or when venous compression with deep vein thrombosis is present, aggressive measures should be taken. Particularly in young patients, an appropriate approach is surgical exploration with hematoma evacuation and arterial repair by means of arterial suture, patch angioplasty, or graft interposition.

In elderly patients, we consider endovascular exclusion with a covered stent-graft the treatment of choice. A severely compromised arterial wall generally leads to difficult surgical repair that involves major revascularization and carries an increased risk of morbidity and death after open surgery.

In most patients, we maintain that a fasciotomy of the thigh should be routinely carried out to avoid severe complications such as nerve and graft compression, deep vein thrombosis, and secondary infection with abscess formation.

In conclusion, we believe that spontaneous rupture of the superficial femoral artery should be suspected in cases of spontaneous swelling of the thigh in the absence of trauma or other apparent causes. Magnetic resonance imaging and angiography seem to be the most effective methods by which to confirm a diagnosis.