CASE R E P O R T
Aneurysms of the superficial femoral artery: A report of two cases and review of the literature E d w a r d E. R i g d o n , M D , and N a v i d M o n a j j e m , M D , Jackson, Miss. True "arteriosclerotic" aneurysms of the superficial femoral artery, not associated with generalized dilatation of the common femoral or popliteal artery, are relatively rare. We report our experience with two isolated superficial femoral artery aneurysms and review the previous literature. An 88-year-old woman was first seen with thrombosis of a superficial femoral aneurysm and limb-threatening ischemia and had eventual limb loss as a result of occlusion of distal rtm-offvessels despite surgical revascularization. A 93-year-old man came to us with rupture and was treated with an interposition graft, which resulted in limb salvage. Review of 17 "arteriosclerotic" superficial femoral artery aneurysms in 14 patients whose cases were reported in the literature revealed a complication at presentation in 65%, rupture in 35%, thrombosis in 18%, and distal emboli in 12%. However, limb salvage was 94% and there were no perioperative deaths. Abdominal aortic aneurysms were discovered in 40%. Males (75%) were more common than females, and the average age was 77 years (range 61 to 93). Isolated superficial femoral artery aneurysms are rare and occur at an older average age than do other peripheral aneurysms, but their incidence is anticipated to increase with this growing segment of our population. In the absence of evidence of syphilitic, other infectious, immunologic, inflammatory, or connective-tissue disorders, these and other aneurysms are considered arteriosclerotic in origin, despite the absence of diffuse arteriosclerosis in many cases and controversy regarding the role of arteriosclerosis in their cause. Because of the rarity of superficial femoral artery aneurysms, there is frequently a delay in diagnosis, and they are first noted with rupture more often than are other peripheral aneurysms. The incidence of critical ischemia as a result of thrombosis or emboli is similar to that associated with other peripheral aneurysms. Superficial femoral artery aneurysms are associated with abdominal aortic aneurysms, as are other peripheral aneurysms. Successful preservation of life and limb is possible with early recognition and surgical reconstruction, which is recommended for patients with aneurysms of the superficial femoral arteries that are 2.5 cm or greater in maximum diameter and for symptomatic aneurysms of any size. (J VASC SURG 1992;16:790-3.)
In reports o f peripheral arterial aneurysms, the occasional involvement o f the supcrficial femoral artery has been noted, but specific information regarding these unusual aneurysms has often been omitted. TM Detailed reports o f isolated, true "arteriosclerotic" aneurysms o f the superficial femoral artery have been rare, 5-n and there is limited infor-
marion to assess their incidence, m o d e o f presentation, natural history, association with other peripheral aneurysms, and response to treatment. O u r experience with two isolated superficial femoral artery aneurysms is described, and the literature available concerning these aneurysms is reviewed and analyzed.
From the Department of Surgery, University of Mississippi Medical Center, Jackson. Reprint requests: Edward "E. Rigdon, MD, Department of Surgery, Universityof Mississippi Medical Center, 2500 North State St., Jackson, MS 39216-4505. 24/4/38152
CASE REPORTS Case 1. A 9B-year-old black man was referred to us because of a rapidly expanding painful mass in the midportion of his right thigh. The mass had initially been observed approximately i year previously, at which time he was told it was metastatic prostate cancer and did not need
790
Volume 16 Number 5 November 1992
Aneurysms of the supeoqcialfemoral artery 791
Fig. 1. Computerized tomographic scan of both thighs of patient in case 1. Maximum diameter of aneurysm of right superficial femoral artery is 12 cm in midthigh (solidarrow). Left superficial femoral artery is 1.7 cm in maximum diameter (open arrow). Extravasation of blood into soft tissue of thigh was observed in view slightly cephalad to region of maximum diameter of aneurysm (not shown). treatment. One week before admission he was hospitalized because of urinary retention, and during hospitalization the right thigh mass began to expand rapidly and became intensely painful. The patient had not received long- or short-term anticoagulant or antiplatelet therapy. A scan by computerized tomography (Fig. 1) revealed a 12 cm aneurysm of the right superficial femoral artery, with evidence of rupture into the soft tissue of the thigh. The contralateral midsuperficial femoral artery was minimally dilated to 1.7 cm. No common or deep femoral, popliteal, or aortic aneurysms were noted. On admission, the patient was alert and hemodynamically stable. The large right thigh mass was markedly tender and pulsatile, with ecchymotic discoloration of surrounding soft tissues. The pedal pulses were normal, and there was no evidence of distal ischemia or emboli. There were no palpable aneurysms of the aorta or other peripheral arteries. An urgent operation was performed, revealing a true aneurysm of the midportion of the superficial femoral artery with rupture into the soft tissue of the thigh near the region of maximum dilatation. The arterial wall proximal and distal to the aneurysm was free from clinical signs of arteriosclerosis. No evidence of arterial infection, prior injury, or metastatic neoplasm was observed. The wall of the aneurysm revealed no signs of infecting organisms on Gram stain testing of samples obtained intraoperatively. The aneurysmal segment was replaced with a prosthetic interposition graft of 8 m m expanded polytetrafluoroethylene, the large thigh hematoma was evacuated, and patent bleeding branches were ligated from within the aneurysm. Subsequent cultures of the wall of the aneurysm and thrombus, urine, and blood were negative for bacterial, myobacterial, and fungal organisms. Serologic tests for
syphilis were negative. After the operation, the patient made a complete recovery, manifesting no evidence of ischemic or embolic complications after a follow-up period of 12 months. Ultrasound examination at 6 and 12 months revealed no changes in the diameter of the femoral, popliteal, or contralateral superficial femoral arteries or of the abdominal aorta. Case 2. An 88-year-old black woman was admitted to the medical service because of an acute stroke. She had taken aspirin for an unknown period of time before the recent stroke, but had been taking no other anticoagulant before or after the stroke. During hospitalization she was noted to have a painful, cold, pulseless right lower extremity. It was uncertain how long this condition had been present. She had detected a large mass in the midthigh slowly enlarging over a 4-year period, which was prominent and pulsatile on examination. Urgent revascularization was attempted, at which time a thrombosed 5 cm true aneurysm of the superficial femoral artery was discovered. Moderate arteriosclerosis was noted clinically in the artery proximal and distal to the aneurysm. No evidence of prior injury or arterial infection was observed. Good inflow was established from the proximal, nondilated superficial femoral artery by balloon catheter thrombectomy. However, there was little bleeding noted from the distal superficial femoral artery, and thrombectomy catheters would pass only a short distance into the tibial vessels and yielded little acute thrombus. An intraoperative arteriogram revealed diffuse occlusion of all tibial vessels a short distance from their origin, apparently because of previous recurrent emboli from the aneurysm, with minimal runoffinto a few geniculate and proximal tibial branches. Although prognosis for limb salvage was considered poor because of inadequate outflow, revascularization was performed with
~ournalof VASCULAR SURGERY
792 Rigdon and Monajjem
Table I. Summary of reported aneurysms o f the superficial femoral artery
Source
No. of No. of patients aneurysms Rupture
Celi 1984s Cieslik 19896 Hardy 19727 Krernan 19818
1 1 1 6
1 2 1 7
Ormstad 19759 1 Parra 19891° 1 Zanetti 1986n 1 Present study 2 Totals 14
1 1 1 3 17
0 1 0 1
No. of No. of aneurysms No. of other Distal limbs of abdomical peripheral emboli Thrombosis lost aorta aneurysms
0 0 0 1
0 0 0 2
1 0 0 1 0 0 1 0 0 1 1 1 6(35%) 2(12%) 3(18%)
0 0 0 0
NA NA NA 2
Sex
Ages
F
M
0 NA NA 3
70 NA NA 70 NA 63, 71, 1 75, 78, 82, 89 0 1 0 75 0 1 0 83 1 0 NA NA 61 1 1 0 0 88, 93 1 1 1(6%) 4/10(40%) 3/11(27%) Avg., 77; 3(25%) 9(75%) range, 61-93
NA, Not available.
an interposition graft of 8 mm expanded polytetrafluoroethylene. This patient was treated before the institution of our current policy of administering intraoperative thrombolytic infusion in similar circumstances in the attempt to improve outflow by lysis of thrombus that is not removed by balloon catheters. The perfusion of the limb did not improve significantly after repair of the aneu~sm, and above-knee mnputation was performed 2 weeks later when gangrenous changes developed in the foot. Gross examination of the amputated extremity revealed chronic obliteration of the tibial vessels, but a histologic examination was not performed. Serologic and cerebrospinal fluid tests for syphilis were negative. No other peripheral aneurysms were noted on physical examination. Imaging studies were not performed to look for other peripheral aneurysms. During the same hospitalization she had a second stroke and was eventually discharged to a nursing home, after which she was lost to follow-up. REVIEW OF LITERATURE The M E D L A R S computer database o f the National Library of Medicine was searched for all references to aneurysms o f the femoral arteries between 1966 and 1991. Reports before 1966 referred to in these articles were also reviewed. Those concerning mycotic, anastomotic, or other false aneurysms were excluded. Also excluded were reports o f femoral artery aneurysms that did not distinguish aneurysms confined to the superficial femoral artery from those also involving the c o m m o n femoral or popliteal arteries. Table I presents a summary o f the data available from eight reports o f 17 isolated aneurysms o f the superficial femoral artery in 14 patients. DISCUSSION
Aneurysms in peripheral arteries may be associated with such etiologic factors as syphilitic or other
infectious arteritis, noninfectious immunologic or inflammatory arteritis, and connective tissue diseases such as Ehlers-Danlos syndrome. Aneurysms associated with such conditions are frequently multiple, and affected individuals commonly exhibit other manifestations o f the underlying process. In the absence o f such clear etiologic factors, most aneurysms have been attributed to "arteriosclerotic" degeneration, even when there is little or no evidence o f arteriosclerosis in other vessels, as observed in the patient reported in our case 1. Investigations have failed to identify a distinct degenerative process in the majority o f peripheral aneurysms, hence the term arteriosclerotic continues to be applied to those without evidence o f other causes. Isolated "arteriosclerotic" true aneurysms o f the superficial femoral arteries are rare, and there is little data regarding their method o f presentation, natural history, association with other aneurysms, or selection and outcome o f treatment. The two cases reported in our experience indicated to us that these aneurysms are likely to occur in the more elderly population, to be discovered only after the onset o f significant complications, and to carry a significant incidence o f morbidity. Our review o f the literature available concerning aneurysms o f the superficial femoral artery confirmed these suspicions, with 35% being first seen after the onset o f rupture, compared with only 7% o f c o m m o n femoral and popliteal aneurysms presenting with this complication in our institution (unpublished data). An unexpected discovery was that thrombosis and limb ischemia were present in only 18% and evidence o f distal embolic events in only 12%, with limb salvage possible in 94%. This is contrasted with the 31% incidence o f thrombosis, 3% incidence of distal emboli, and 82%
Volume 16 Number 5 November 1992
limb salvage rate in our series of common femoral and popliteal aneurysms. The discovery of aneurysms of the abdominal aorta in 40% of patients with reported cases of superficial femoral artery aneurysms is consistent with the concept that a systemic vascular connective tissue degeneration may be responsible for their development, either as a consequence of or unrelated to arteriosclerosis. This is also remarkably similar to the incidence of abdominal aortic aneurysms in 37% of our patients with common femoral or popliteal aneurysms and with other reports.~4 As suggested by others, we believe the superficial femoral artery is relatively more protected against the development of aneurysms than the common femoral or popliteal arteries, with excellent muscular support and absence of bending stress, s,8 The average age of patients in the literature who had superficial femoral aneurysm was 77 years, contrasted with the significantly younger mean age of 66 years for our patients with common femoral or popliteal aneurysms. It is reasonable to anticipate that the frequency with which vascular surgeons encounter aneurysms of the superficial femoral artery will increase as the number of extremely elderly persons in our population increases. Like other peripheral aneurysms, superficial femoral aneurysms should serve as a marker of high risk of developing other peripheral aneurysms and should prompt appropriate diagnostic evaluations of the aorta and other peripheral arteries. Questions remain concerning the true incidence and natural history of aneurysms of the superficial femoral artery. The small number reported does not provide sufficient data to indicate the overall incidence of complications, the risk of complications relative to the maximum diameter of the aneurysm, or the risk of progressive enlargement Knot surgically repaired. However, these aneurysms clearly may produce limb- and life-threatening complications even when relatively small in size, and the risks of mortality and complications after surgical repair are quite low. It has been suggested that common femoral and popliteal aneurysms be repaired if the maximum diameter is greater than 2 to 2.5 cm, since the incidence of serious compfications is low for those less than 2 cm. 12,13 The risks of complications associated with aneurysms of the superficial femoral artery appear at least as great as the risks associated with aneurysms of the common femoral and popliteal arteries, Therefore, we recommend surgical repair of
Aneurysms of the superficialfemoral arteU 793
all asymptomatic superficial femoral aneurysms 2.5 cm or greater in maximum diameter in the absence of major contraindications to elective surgery, as well as tbr those of any size presenting with the complications of rupture, thrombosis, distal embolization, or compression of contiguous structures (such as neuropathy or venous occlusion). As with other peripheral aneurysms, repair should generally consist of ligation of the artery proximal and distal to the aneurysm and revascularization with bypass of the ligated segment. Ruptured aneurysms may require endoaneurysmal ligation of patent, bleeding branches. The choice of graft material for revascularization should be autogenous vein in most cases, with prosthetic material serving as an acceptable alternative when autogenous vein is unavailable or when the patient's condition dictates performance of the most expeditious repair possible. REFERENCES
1. Adiseshiah M, Bailey DA. Aneurysms of the femoral artery. Br J Surg 1977;64:174-6. 2. Curler B, Darling RC. Surgical management of arteriosclerotic femoral aneurysms. Surgery 1973;74:764-73. 3. Dent TL, Lindenauer SM, Ernst CB, Fry WJ. Multiple arteriosclerotic arterial aneurysms. Arch Surg 1972;105:33844. 4. Pappas G, Janes J-M, Bernatz PE, et al. Femoral aneurysms. JAMA 1964;190:489-93. 5. Ceil S, Mandolfmo T, Micali C, Castiglione N. Aneurysm of the superficial femoral artery. Chir Ital 1984;36:260-5. 6. Cieslik R, Pasierbski J, Reizer E, Dmytrzak A. Superficial femoral artery aneurysm with imminent rupture. Wiad Lek 1989;42: 334-6. 7. Hardy DG, Eadie DGA. Femoral aneurysms. Br J Surg 1972;59:614-6. 8. Kremen l, Menzoian JO, Corson JD, Bush HL, LoGerfo FW. Atherosclerotic aneurysms of the superficial femoral artery: a literature review and report of six additional cases. Am Surg 1981;47:338-42. 9. Ormstad K, Solheim K. Ruptured aneurysm of the superficial femoral artery. Scand J Thorac Cardiovasc Surg 1975;9: 181-2. 10. Parra H_H, Bark T, Swedenborg J. Ruptured atherosclerotic aneurysm of the superficial femoral artery: case report. Acta Chir Scand 1989 Sep;155(9):493-4. 11. Zanetti PP, Personnertaz E, Peradotto F, Rosa G, Battaglia C. Aneurysm of the superficial femoral artery. Minerva Cardioangiol 1986;34:323-7. 12. Graham LM, Zelenock GB, Whitehouse WM, et al. Clinical significance of arteriosclerotic femoral artery aneurysms. Arch Surg 1980;115:502-6. 13. Shorter CK, DeWeese ]A, Ouriel K, Green RM. Popliteal artery aneurysms: a 25-year surgical experience, l Vase SURG 1991;14:771-6. Submitted Jan. 22, 1992; accepted March 24, 1992.
Aneurysms of the superficial femoral artery: A report of two cases and review of the literature E d w a r d E. R i g d o n , M D , and N a v i d M o n a j j e m , M D , Jackson, Miss. True "arteriosclerotic" aneurysms of the superficial femoral artery, not associated with generalized dilatation of the common femoral or popliteal artery, are relatively rare. We report our experience with two isolated superficial femoral artery aneurysms and review the previous literature. An 88-year-old woman was first seen with thrombosis of a superficial femoral aneurysm and limb-threatening ischemia and had eventual limb loss as a result of occlusion of distal rtm-offvessels despite surgical revascularization. A 93-year-old man came to us with rupture and was treated with an interposition graft, which resulted in limb salvage. Review of 17 "arteriosclerotic" superficial femoral artery aneurysms in 14 patients whose cases were reported in the literature revealed a complication at presentation in 65%, rupture in 35%, thrombosis in 18%, and distal emboli in 12%. However, limb salvage was 94% and there were no perioperative deaths. Abdominal aortic aneurysms were discovered in 40%. Males (75%) were more common than females, and the average age was 77 years (range 61 to 93). Isolated superficial femoral artery aneurysms are rare and occur at an older average age than do other peripheral aneurysms, but their incidence is anticipated to increase with this growing segment of our population. In the absence of evidence of syphilitic, other infectious, immunologic, inflammatory, or connective-tissue disorders, these and other aneurysms are considered arteriosclerotic in origin, despite the absence of diffuse arteriosclerosis in many cases and controversy regarding the role of arteriosclerosis in their cause. Because of the rarity of superficial femoral artery aneurysms, there is frequently a delay in diagnosis, and they are first noted with rupture more often than are other peripheral aneurysms. The incidence of critical ischemia as a result of thrombosis or emboli is similar to that associated with other peripheral aneurysms. Superficial femoral artery aneurysms are associated with abdominal aortic aneurysms, as are other peripheral aneurysms. Successful preservation of life and limb is possible with early recognition and surgical reconstruction, which is recommended for patients with aneurysms of the superficial femoral arteries that are 2.5 cm or greater in maximum diameter and for symptomatic aneurysms of any size. (J VASC SURG 1992;16:790-3.)
In reports o f peripheral arterial aneurysms, the occasional involvement o f the supcrficial femoral artery has been noted, but specific information regarding these unusual aneurysms has often been omitted. TM Detailed reports o f isolated, true "arteriosclerotic" aneurysms o f the superficial femoral artery have been rare, 5-n and there is limited infor-
marion to assess their incidence, m o d e o f presentation, natural history, association with other peripheral aneurysms, and response to treatment. O u r experience with two isolated superficial femoral artery aneurysms is described, and the literature available concerning these aneurysms is reviewed and analyzed.
From the Department of Surgery, University of Mississippi Medical Center, Jackson. Reprint requests: Edward "E. Rigdon, MD, Department of Surgery, Universityof Mississippi Medical Center, 2500 North State St., Jackson, MS 39216-4505. 24/4/38152
CASE REPORTS Case 1. A 9B-year-old black man was referred to us because of a rapidly expanding painful mass in the midportion of his right thigh. The mass had initially been observed approximately i year previously, at which time he was told it was metastatic prostate cancer and did not need
790
Volume 16 Number 5 November 1992
Aneurysms of the supeoqcialfemoral artery 791
Fig. 1. Computerized tomographic scan of both thighs of patient in case 1. Maximum diameter of aneurysm of right superficial femoral artery is 12 cm in midthigh (solidarrow). Left superficial femoral artery is 1.7 cm in maximum diameter (open arrow). Extravasation of blood into soft tissue of thigh was observed in view slightly cephalad to region of maximum diameter of aneurysm (not shown). treatment. One week before admission he was hospitalized because of urinary retention, and during hospitalization the right thigh mass began to expand rapidly and became intensely painful. The patient had not received long- or short-term anticoagulant or antiplatelet therapy. A scan by computerized tomography (Fig. 1) revealed a 12 cm aneurysm of the right superficial femoral artery, with evidence of rupture into the soft tissue of the thigh. The contralateral midsuperficial femoral artery was minimally dilated to 1.7 cm. No common or deep femoral, popliteal, or aortic aneurysms were noted. On admission, the patient was alert and hemodynamically stable. The large right thigh mass was markedly tender and pulsatile, with ecchymotic discoloration of surrounding soft tissues. The pedal pulses were normal, and there was no evidence of distal ischemia or emboli. There were no palpable aneurysms of the aorta or other peripheral arteries. An urgent operation was performed, revealing a true aneurysm of the midportion of the superficial femoral artery with rupture into the soft tissue of the thigh near the region of maximum dilatation. The arterial wall proximal and distal to the aneurysm was free from clinical signs of arteriosclerosis. No evidence of arterial infection, prior injury, or metastatic neoplasm was observed. The wall of the aneurysm revealed no signs of infecting organisms on Gram stain testing of samples obtained intraoperatively. The aneurysmal segment was replaced with a prosthetic interposition graft of 8 m m expanded polytetrafluoroethylene, the large thigh hematoma was evacuated, and patent bleeding branches were ligated from within the aneurysm. Subsequent cultures of the wall of the aneurysm and thrombus, urine, and blood were negative for bacterial, myobacterial, and fungal organisms. Serologic tests for
syphilis were negative. After the operation, the patient made a complete recovery, manifesting no evidence of ischemic or embolic complications after a follow-up period of 12 months. Ultrasound examination at 6 and 12 months revealed no changes in the diameter of the femoral, popliteal, or contralateral superficial femoral arteries or of the abdominal aorta. Case 2. An 88-year-old black woman was admitted to the medical service because of an acute stroke. She had taken aspirin for an unknown period of time before the recent stroke, but had been taking no other anticoagulant before or after the stroke. During hospitalization she was noted to have a painful, cold, pulseless right lower extremity. It was uncertain how long this condition had been present. She had detected a large mass in the midthigh slowly enlarging over a 4-year period, which was prominent and pulsatile on examination. Urgent revascularization was attempted, at which time a thrombosed 5 cm true aneurysm of the superficial femoral artery was discovered. Moderate arteriosclerosis was noted clinically in the artery proximal and distal to the aneurysm. No evidence of prior injury or arterial infection was observed. Good inflow was established from the proximal, nondilated superficial femoral artery by balloon catheter thrombectomy. However, there was little bleeding noted from the distal superficial femoral artery, and thrombectomy catheters would pass only a short distance into the tibial vessels and yielded little acute thrombus. An intraoperative arteriogram revealed diffuse occlusion of all tibial vessels a short distance from their origin, apparently because of previous recurrent emboli from the aneurysm, with minimal runoffinto a few geniculate and proximal tibial branches. Although prognosis for limb salvage was considered poor because of inadequate outflow, revascularization was performed with
~ournalof VASCULAR SURGERY
792 Rigdon and Monajjem
Table I. Summary of reported aneurysms o f the superficial femoral artery
Source
No. of No. of patients aneurysms Rupture
Celi 1984s Cieslik 19896 Hardy 19727 Krernan 19818
1 1 1 6
1 2 1 7
Ormstad 19759 1 Parra 19891° 1 Zanetti 1986n 1 Present study 2 Totals 14
1 1 1 3 17
0 1 0 1
No. of No. of aneurysms No. of other Distal limbs of abdomical peripheral emboli Thrombosis lost aorta aneurysms
0 0 0 1
0 0 0 2
1 0 0 1 0 0 1 0 0 1 1 1 6(35%) 2(12%) 3(18%)
0 0 0 0
NA NA NA 2
Sex
Ages
F
M
0 NA NA 3
70 NA NA 70 NA 63, 71, 1 75, 78, 82, 89 0 1 0 75 0 1 0 83 1 0 NA NA 61 1 1 0 0 88, 93 1 1 1(6%) 4/10(40%) 3/11(27%) Avg., 77; 3(25%) 9(75%) range, 61-93
NA, Not available.
an interposition graft of 8 mm expanded polytetrafluoroethylene. This patient was treated before the institution of our current policy of administering intraoperative thrombolytic infusion in similar circumstances in the attempt to improve outflow by lysis of thrombus that is not removed by balloon catheters. The perfusion of the limb did not improve significantly after repair of the aneu~sm, and above-knee mnputation was performed 2 weeks later when gangrenous changes developed in the foot. Gross examination of the amputated extremity revealed chronic obliteration of the tibial vessels, but a histologic examination was not performed. Serologic and cerebrospinal fluid tests for syphilis were negative. No other peripheral aneurysms were noted on physical examination. Imaging studies were not performed to look for other peripheral aneurysms. During the same hospitalization she had a second stroke and was eventually discharged to a nursing home, after which she was lost to follow-up. REVIEW OF LITERATURE The M E D L A R S computer database o f the National Library of Medicine was searched for all references to aneurysms o f the femoral arteries between 1966 and 1991. Reports before 1966 referred to in these articles were also reviewed. Those concerning mycotic, anastomotic, or other false aneurysms were excluded. Also excluded were reports o f femoral artery aneurysms that did not distinguish aneurysms confined to the superficial femoral artery from those also involving the c o m m o n femoral or popliteal arteries. Table I presents a summary o f the data available from eight reports o f 17 isolated aneurysms o f the superficial femoral artery in 14 patients. DISCUSSION
Aneurysms in peripheral arteries may be associated with such etiologic factors as syphilitic or other
infectious arteritis, noninfectious immunologic or inflammatory arteritis, and connective tissue diseases such as Ehlers-Danlos syndrome. Aneurysms associated with such conditions are frequently multiple, and affected individuals commonly exhibit other manifestations o f the underlying process. In the absence o f such clear etiologic factors, most aneurysms have been attributed to "arteriosclerotic" degeneration, even when there is little or no evidence o f arteriosclerosis in other vessels, as observed in the patient reported in our case 1. Investigations have failed to identify a distinct degenerative process in the majority o f peripheral aneurysms, hence the term arteriosclerotic continues to be applied to those without evidence o f other causes. Isolated "arteriosclerotic" true aneurysms o f the superficial femoral arteries are rare, and there is little data regarding their method o f presentation, natural history, association with other aneurysms, or selection and outcome o f treatment. The two cases reported in our experience indicated to us that these aneurysms are likely to occur in the more elderly population, to be discovered only after the onset o f significant complications, and to carry a significant incidence o f morbidity. Our review o f the literature available concerning aneurysms o f the superficial femoral artery confirmed these suspicions, with 35% being first seen after the onset o f rupture, compared with only 7% o f c o m m o n femoral and popliteal aneurysms presenting with this complication in our institution (unpublished data). An unexpected discovery was that thrombosis and limb ischemia were present in only 18% and evidence o f distal embolic events in only 12%, with limb salvage possible in 94%. This is contrasted with the 31% incidence o f thrombosis, 3% incidence of distal emboli, and 82%
Volume 16 Number 5 November 1992
limb salvage rate in our series of common femoral and popliteal aneurysms. The discovery of aneurysms of the abdominal aorta in 40% of patients with reported cases of superficial femoral artery aneurysms is consistent with the concept that a systemic vascular connective tissue degeneration may be responsible for their development, either as a consequence of or unrelated to arteriosclerosis. This is also remarkably similar to the incidence of abdominal aortic aneurysms in 37% of our patients with common femoral or popliteal aneurysms and with other reports.~4 As suggested by others, we believe the superficial femoral artery is relatively more protected against the development of aneurysms than the common femoral or popliteal arteries, with excellent muscular support and absence of bending stress, s,8 The average age of patients in the literature who had superficial femoral aneurysm was 77 years, contrasted with the significantly younger mean age of 66 years for our patients with common femoral or popliteal aneurysms. It is reasonable to anticipate that the frequency with which vascular surgeons encounter aneurysms of the superficial femoral artery will increase as the number of extremely elderly persons in our population increases. Like other peripheral aneurysms, superficial femoral aneurysms should serve as a marker of high risk of developing other peripheral aneurysms and should prompt appropriate diagnostic evaluations of the aorta and other peripheral arteries. Questions remain concerning the true incidence and natural history of aneurysms of the superficial femoral artery. The small number reported does not provide sufficient data to indicate the overall incidence of complications, the risk of complications relative to the maximum diameter of the aneurysm, or the risk of progressive enlargement Knot surgically repaired. However, these aneurysms clearly may produce limb- and life-threatening complications even when relatively small in size, and the risks of mortality and complications after surgical repair are quite low. It has been suggested that common femoral and popliteal aneurysms be repaired if the maximum diameter is greater than 2 to 2.5 cm, since the incidence of serious compfications is low for those less than 2 cm. 12,13 The risks of complications associated with aneurysms of the superficial femoral artery appear at least as great as the risks associated with aneurysms of the common femoral and popliteal arteries, Therefore, we recommend surgical repair of
Aneurysms of the superficialfemoral arteU 793
all asymptomatic superficial femoral aneurysms 2.5 cm or greater in maximum diameter in the absence of major contraindications to elective surgery, as well as tbr those of any size presenting with the complications of rupture, thrombosis, distal embolization, or compression of contiguous structures (such as neuropathy or venous occlusion). As with other peripheral aneurysms, repair should generally consist of ligation of the artery proximal and distal to the aneurysm and revascularization with bypass of the ligated segment. Ruptured aneurysms may require endoaneurysmal ligation of patent, bleeding branches. The choice of graft material for revascularization should be autogenous vein in most cases, with prosthetic material serving as an acceptable alternative when autogenous vein is unavailable or when the patient's condition dictates performance of the most expeditious repair possible. REFERENCES
1. Adiseshiah M, Bailey DA. Aneurysms of the femoral artery. Br J Surg 1977;64:174-6. 2. Curler B, Darling RC. Surgical management of arteriosclerotic femoral aneurysms. Surgery 1973;74:764-73. 3. Dent TL, Lindenauer SM, Ernst CB, Fry WJ. Multiple arteriosclerotic arterial aneurysms. Arch Surg 1972;105:33844. 4. Pappas G, Janes J-M, Bernatz PE, et al. Femoral aneurysms. JAMA 1964;190:489-93. 5. Ceil S, Mandolfmo T, Micali C, Castiglione N. Aneurysm of the superficial femoral artery. Chir Ital 1984;36:260-5. 6. Cieslik R, Pasierbski J, Reizer E, Dmytrzak A. Superficial femoral artery aneurysm with imminent rupture. Wiad Lek 1989;42: 334-6. 7. Hardy DG, Eadie DGA. Femoral aneurysms. Br J Surg 1972;59:614-6. 8. Kremen l, Menzoian JO, Corson JD, Bush HL, LoGerfo FW. Atherosclerotic aneurysms of the superficial femoral artery: a literature review and report of six additional cases. Am Surg 1981;47:338-42. 9. Ormstad K, Solheim K. Ruptured aneurysm of the superficial femoral artery. Scand J Thorac Cardiovasc Surg 1975;9: 181-2. 10. Parra H_H, Bark T, Swedenborg J. Ruptured atherosclerotic aneurysm of the superficial femoral artery: case report. Acta Chir Scand 1989 Sep;155(9):493-4. 11. Zanetti PP, Personnertaz E, Peradotto F, Rosa G, Battaglia C. Aneurysm of the superficial femoral artery. Minerva Cardioangiol 1986;34:323-7. 12. Graham LM, Zelenock GB, Whitehouse WM, et al. Clinical significance of arteriosclerotic femoral artery aneurysms. Arch Surg 1980;115:502-6. 13. Shorter CK, DeWeese ]A, Ouriel K, Green RM. Popliteal artery aneurysms: a 25-year surgical experience, l Vase SURG 1991;14:771-6. Submitted Jan. 22, 1992; accepted March 24, 1992.
