Bilateral popliteal aneurysm as a result of vascular type IV entrapment in a young patient: A report of an exceptional case Diego López Garcia, MD, Miguel A. G. Arranz, MD, Salvador Tagarro, MD, Santiago R. Camarero, MD, M. Emma Gonzalez, MD, and Miguel G. Gimeno, MD, La Rioja, Spain Popliteal artery entrapment syndrome is recognized as a cause of claudication and arterial occlusion in young patients. Aneurysmal degeneration is a reported but rare complication. We present the case of a young male patient with large bilateral popliteal aneurysms due to symptomatic anatomic entrapment. The left aneurysm was acutely thrombosed, and urgent bypass surgery was required. The contralateral aneurysm was resected by a posterior approach and replaced with an autologous vein graft. Type IV popliteal entrapment by a fibrous band independent of the gastrocnemius muscle was diagnosed during surgery and divided. Early detection of popliteal entrapment is highly important to prevent the development of this serious complication. ( J Vasc Surg 2007;46:1047-50.)
Popliteal artery entrapment syndrome (PAES) is an uncommon although important cause of intermittent claudication in young adults. It is caused by the anomalous interrelationship between the popliteal artery and its surrounding musculofibrotendinous structures. Its progressive and aggressive natural history due to repeated arterial microtrauma can lead to complications such as stenosis, occlusion, and aneurysmal degeneration. In this report, we present the unusual case of a young patient with bilateral popliteal aneurysms as a result of PAES, complicated with acute ischemia, which can be very representative of the potential hazard of this clinical entity. CASE REPORT A 31-year-old athletic young man who was a smoker, had hereditary hypercholesterolemia, and was receiving statin treatment was transferred to our outpatient department with a 2-year history of bilateral calf and plantar lower limb claudication with intense exercise. Moreover, he related a slight pain located at the left popliteal fossa during the last 6 months. Physical examination was highly remarkable for the presence of bilateral pulsatile popliteal masses; pedal pulses were positive, and the ankle-brachial index was normal at rest in both extremities. PAES maneuvers were positive bilaterally, with diminishing pulses with forced plantar flexion. Duplex ultrasonography demonstrated large, bilateral popliteal aneurysms. Further assessment for diagnosis was undertaken with contrast-enhanced computed tomography angiography, which confirmed a 3.5-cm-diameter right popliteal aneurysm and a 5-cm left popliteal aneurysm, both with a saccular shape and extensive mural thrombus and both situated at the mid portion of From the Department of Vascular Surgery, Hospital San Pedro, Logroño. Competition of interest: none. Reprint requests: Diego López García, MD, Department of Vascular Surgery, Hospital San Pedro, C/ Piqueras, 98, Logroño, La Rioja, Spain (e-mail:
[email protected]). 0741-5214/$32.00 Copyright © 2007 by The Society for Vascular Surgery. doi:10.1016/j.jvs.2007.06.032
the popliteal artery (Fig 1). No muscular abnormalities were discovered. Both the small and great saphenous veins were evaluated with duplex ultrasonography and found to be suitable for use in bypass grafting. Written informed consent was obtained to undergo operation first on the left popliteal aneurysm. Five days later, the patient was admitted at our emergency department with a 24-hour history of pain and pallor of the left foot and presented with acute limb-threatening ischemia with both mild sensory and motor deficits and an absence of popliteal and pedal pulses. An urgent digital subtraction angiogram was performed and revealed occlusion of the left popliteal aneurysm with poor distal reconstitution (Fig 2). The patient was taken urgently to the operating room for surgical intervention. Under general anesthesia, the proximal and distal popliteal arteries were exposed by means of a medial approach; after distal thrombectomy and local thrombolysis with infusion of 100,000 units of urokinase to complete lysis of residual thrombus, a reversed great saphenous vein graft, anatomically tunneled, was performed, and aneurysm exclusion was performed. The patient recovered uneventfully and was discharged to home on postoperative day 6 with palpable pedal pulses and no ischemic symptoms. One month after discharge, the patient returned to the operating room for elective repair of the right popliteal aneurysm. He was placed in the prone position, and a posterior approach with an S-shaped incision was performed. Aneurysmal degeneration secondary to popliteal entrapment by a fibrous band not dependent on the gastrocnemius muscle (type IV entrapment) was noted (Fig 3). The band was divided, and the aneurysm was resected and replaced with a reversed small saphenous vein graft. No purulent collections or inflammatory signs were present. Blood cultures were negative. Histopathologic analysis revealed marked degenerative changes of the media with fibrous tissue replacement, isolated inflammatory cell infiltrates, and vessel wall disruption. The postoperative course was uncomplicated, and the patient was discharged home with antiplatelet therapy and a recommendation for cessation of tobacco use. After 6 months, the patient was asymptomatic, with a return to previous activity. Pedal pulses remained palpable bilaterally. Control magnetic resonance angiography and
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Fig 1. A, Preoperative cross-sectional computed tomography angiography: 3.5-cm right popliteal aneurysm with mural thrombus. B, Preoperative cross-sectional computed tomography angiography: 5-cm left popliteal aneurysm before thrombosis. No abnormal musculotendinous compression was shown. duplex ultrasonography showed patency of both grafts with no evidence of stenosis or acquired entrapment and a normal Doppler waveform.
DISCUSSION PAES has been recognized as a cause of claudication and arterial occlusion in young patients. Recently published clinical review articles have revealed a growing awareness of what was previously considered a rare clinical condition and suggest that screening and aggressive treatment for this syndrome must be considered.1 A history of calf and foot claudication in a young (often male) athletic individual with an absence of atherosclerotic risk factors defines the typical clinical picture. An absence of foot pulses with passive dorsiflexion and active plantar flexion is characteristic but not specific for this condition.2 Therefore, further diagnostic imaging is necessary to confirm the diagnosis and plan surgical intervention. We chose computed tomography angiography as the preoperative imaging modality in this case. Computed tomography angiography may be the procedure of choice in young adults with intermittent
Fig 2. A, Arteriogram demonstrates abrupt occlusion of the mid portion of the left popliteal artery, corresponding to the thrombosed aneurysm. A slight deviation toward the lateral side can be observed. A saccular patent right popliteal aneurysm can also be seen. B, Poor distal recanalization with extensive distal thrombosis of the anterior and posterior tibial arteries; the peroneal artery is patent but partially filled by thrombus.
claudication and is demonstrated to be a very sensitive diagnostic modality for PAES.3 Moreover, as with magnetic resonance angiography, it can be used to delineate in detail the anatomy of the popliteal fossa. Positional digital contrast angiography is also very useful when complications occur and can show medial or, less commonly, lateral arterial deviation; other typical findings include focal narrowing or occlusion of the mid popliteal artery, aneurysm degeneration, and distal embolic occlusion.4,5 Type IV entrapment by the popliteal muscle or a fibrous remnant band is the least commonly diagnosed but
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Fig 3. An operative photograph demonstrates right popliteal aneurysm distal to compression by a fibrous band.
probably has the most aggressive natural history for popliteal artery damage.6,7 It is due to the anomalous development of the popliteal artery and is independent of migration of the medial head of the gastrocnemius muscle. In this case, a fibrous band not dependent on the medial gastrocnemius head was discovered on the right side, and this band widely surrounded both the popliteal artery and vein, producing arterial compression and poststenotic dilation due to mechanical stress. On the left side, the artery was displaced laterally; therefore, we suppose a type III or IV PAES was present, but we cannot be sure because the medial approach used for emergency repair of the popliteal artery occlusion does not allow adequate exposure of the zone of compression. The pathology of PAES is believed to be progressive, with arterial thrombosis occurring in some individuals when the arterial intima is damaged or secondary to aneurysm degeneration. In this case, mural thrombus from the area of aneurysmal degeneration probably embolized to the distal runoff vessels and led to thrombosis. Surgical treatment must be mandatory if anatomic entrapment is confirmed. If the popliteal artery wall is undamaged, musculotendinous section alone will be enough. If the artery appears diseased or is thrombosed, then musculotendinous section and arterial reconstruction must be performed. Autologous saphenous vein interposition grafting is demonstrated to be the best treatment of PAES when the artery
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must be replaced.1 Resection with primary anastomosis of undiseased arterial segments may be appropiate in children.8 Percutaneous thromboembolectomy, local thrombolysis, and percutaneous transluminal dilatation has been described in the case of thromboembolic complications of PAES in young patients, always followed by musculotendinous section, but long-term results have not yet been evaluated.9 Thrombolytic therapy for treatment of popliteal artery aneurysm acute thrombosis is widely described.4,10 Thrombolytic therapy does not obviate surgery but may allow a less extensive procedure to be performed. In this case, the leg with the thrombosed aneurysm had limb-threatening ischemia that precluded prolonged treatment with fibrinolytic therapy, so we preferred direct surgical intervention. The selection of the approach to the popliteal artery is controversial. Some authors1 prefer a medial approach because it offers an easy way to extend repair of the popliteal artery more distally and is associated with a quicker return to activity. In contrast, the posterior approach allows a better appreciation of popliteal anatomy.11 In the acutely thrombosed limb, we preferred a medial approach for intervention because it was performed on an urgent basis and bypass was needed. The second intervention was accomplished via a posterior approach and showed the strict relationship of the artery with the fibrous band, thus allowing an easy reconstruction. Unilateral aneurysm degeneration due to popliteal artery entrapment is not frequent, but bilateral aneurysms, as in this report, are exceptional. In the report of Gyftokostas et al,12 10 cases of popliteal aneurysm were documented for an overall of 74 cases of popliteal entrapment. In the large series of Levien and Veller,1 8 popliteal aneurysms in 88 limbs with entrapment were reported. Unilateral popliteal aneurysms have also been described in children.8,13 In conclusion, in the presence of popliteal artery aneurysm in young patients, popliteal entrapment must be considered. Surgical resection with vein interposition grafting for repair is the procedure of choice. Early diagnosis of this disease is highly important to prevent development of this complication. REFERENCES 1. Levien LJ, Veller MB. Popliteal artery entrapment syndrome: more common than previously recognized. J Vasc Surg 1999;30:587-98. 2. Erdoes LS, Devine JJ, Bernhard VM, Baker MR, Berman SS, Hunter GC. Popliteal vascular compression in a normal population. J Vasc Surg 1994;20:978-86. 3. Ohara N, Miyata T, Oshiro H, Shigematsu H. Surgical treatment for popliteal artery entrapment syndrome. Cardiovasc Surg 2001;9:141-4. 4. Ring DH, Haines GA, Miller DL. Popliteal artery entrapment syndrome: arteriographic findings and thrombolytic therapy. J Vasc Interv Radiol 1999;10:713-21. 5. Fong H, Downs AR. Popliteal artery entrapment syndrome with distal embolization. A report of two cases. J Cardiovasc Surg 1989;30:85-8. 6. Rich NM, Collins GJ, McDonald PT, Kozloff L, Clagett GP, Collins JT. Popliteal vascular entrapment; its increasing interest. Arch Surg 1979; 114:1377-84. 7. Haimovici H, Sprayregen S, Johnson F. Popliteal artery entrapment by fibrous band. Surgery 1972;72:789-92.
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8. Bernheim JW, Hansen J, Faries P, Kilaru S, Winchester P, Mousa A, et al. Acute lower extremity in a 7-year-old boy: an unusual case of popliteal entrapment syndrome. J Vasc Surg 2004;39:1340-3. 9. Steurer J, Hoffmann U, Schneider E, Largiader J, Bollinger A. A new therapeutic approach to popliteal artery entrapment syndrome. Eur J Vasc Endovasc Surg 1995;10:243-7. 10. Dorigo W, Pulli R, Turini F, Pratesi G, Credi G, Innocenti AA, et al. Acute leg ischaemia from thrombosed popliteal artery aneurysms: role of preoperative thrombolysis. Eur J Vasc Endovasc Surg 2002;23: 251-4.
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11. Persky JM, Kempczinsky RF, Fowl RJ. Entrapment of the popliteal artery. Surg Gynecol Obstet 1991;173:84-90. 12. Gyftokostas D, Koutsoumbelis C, Mattheou T, Bouhoutsos J. Poststenotic aneurysms in popliteal artery entrapment syndrome. J Cardiovasc Surg 1991;32:350-2. 13. Haidar S, Thomas K, Miller S. Popliteal artery entrapment syndrome in a young girl. Pediatr Radiol 2005;35:440-3.
Submitted Mar 9, 2007; accepted Jun 13, 2007.
