Original Article
Vein graft aneurysms following popliteal aneurysm repair are more common than we think
Vascular 2015, Vol. 23(5) 494–497 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1708538114557070 vas.sagepub.com
Alistair Sharples, Mark Kay, Timothy Sykes, Anthony Fox and Andrew Houghton
Abstract True infrainguinal vein graft aneurysms are reported infrequently in the literature. We sought to identify the true incidence of these graft aneurysms after popliteal aneurysm repair and identify factors which may increase the risk of such aneurysms developing. Using a prospectively compiled database, we identified patients who underwent a popliteal aneurysm repair between January 1996 and January 2011 at a single district general hospital. Patients were routinely followed up in a graft surveillance programme. Out of 45 patients requiring repair of a popliteal aneurysm over a 15-year period, four (8.8%) patients developed aneurysmal graft disease. Of the patients who developed graft aneurysms, all had aneurysmal disease at other sites compared with 18 (45.0%) patients who did not develop graft aneurysms. Patients with graft aneurysms had a mean of 1.60 aneurysms elsewhere compared to 0.58 in patients with non-aneurysmal grafts (P ¼ 0.005). True vein graft aneurysms occur in a significant number of patients following popliteal aneurysm repair. Our data would suggest this to be more likely in patients who have aneurysms elsewhere and therefore a predisposition to aneurysmal disease. It may be appropriate for patients with aneurysms at other sites to undergo more prolonged postoperative graft surveillance.
Keywords Aneurysmal disease, popliteal aneurysm
Introduction
Materials and methods
Popliteal aneurysms are the most common peripheral aneurysm. They typically affect middle-aged men. It is generally accepted that there is a genetic aspect to aneurysmal disease. Popliteal aneurysms are commonly associated with aneurysms at other locations. Forty percent of patients with a popliteal aneurysm will have an abdominal aortic aneurysm (AAA) and 50% will have bilateral popliteal aneurysms.1 True saphenous vein aneurysms after coronary artery bypass grafting (CABG) are uncommon but well documented.2 However, despite the widespread use of the saphenous vein as the favoured conduit for infrainguinal bypass surgery relatively little has been written on infrainguinal vein graft aneurysms. Below we describe our experiences of saphenous vein graft aneurysms in patients undergoing exclusion of a popliteal aneurysm.
We retrospectively examined 45 patients who underwent exclusion of a popliteal aneurysm using saphenous vein between January 1999 and December 2006. All the procedures were performed by or under the immediate supervision of one of three experienced vascular consultants. Information for analysis was obtained from two sources: from a prospectively collated departmental vascular database and from the patients’ case notes. All the procedures were performed from a medial approach with ligation of the native popliteal artery Vascular Surgery Department, Royal Shrewsbury Hospital, Shrewsbury, UK Corresponding author: Alistair Sharples, Royal Shrewsbury Hospital, Mytton Oak Road, Shrewsbury SY3 8XQ, UK. Email: [email protected]
Downloaded from vas.sagepub.com by guest on November 15, 2015
Sharples et al.
495
and reversed saphenous vein bypass. Patients underwent pre-operative vein scanning to assess the quality of their veins. Veins were deemed suitable if they were of a diameter of greater than 2 mm with no evidence of venous incompetence. In addition, veins were inspected intra-operatively by the operating surgeon. Patients who underwent popliteal aneurysm surgery using other techniques or other types of graft material were excluded from the analysis. Both elective and emergency procedures are included. Preoperatively, all patients underwent imaging of their aorta and lower limb arteries and the presence of any other aneurysms was recorded. Patients underwent duplex graft surveillance scans at 6 weeks, 6, 12, 18 months and based on clinical need thereafter.
Results Forty-five patients underwent exclusion bypass for a popliteal artery aneurysm using a long saphenous vein graft. Forty-four (97.8%) patients were male. The mean age was 71 years. Four (8.8%) patients developed aneurysmal graft disease. All had true aneurysms within the body of the graft. Two underwent elective and two emergency bypass procedures. Only one of the aneurysms was found during the period of graft surveillance with the others discovered during imaging for other reasons. The four cases are presented below. Patient 1 This gentleman was admitted as an emergency with right critical limb ischaemia. Clinically he had a popliteal aneurysm, which had embolised to all the distal vessels. He underwent a bypass using reversed great saphenous vein (GSV). This graft failed two months later and required revision using cephalic vein. Two years later this graft again failed and was revised using GSV from the calf. Eight months later at routine graft surveillance a 15 mm aneurysm was noted in the main body of the vein graft. This was followed up for two years and remained stable and asymptomatic. The patient was then lost to follow up until he represented in 2008 with a critically ischaemic right-leg but with a patent graft. This was likely secondary to embolisation from this aneurysm. Due to poor general health, this was managed conservatively and he died in 2009 from unrelated causes.
good post-operative recovery and 18 months of graft surveillance was completed with no concerns and he was discharged. He represented in 2005 with a nonhealing ulcer on his left ankle. He underwent further ultrasound examination of his graft, which demonstrated there to be two aneurysms of the graft, one at the proximal end measuring 20 mm and one distally, which measured 18 mm. He was managed conservatively and remains asymptomatic. Patient 3 This gentleman had elective repair of a right popliteal aneurysm using reversed GSV in March 2001. He completed the graft surveillance programme with no complications identified. He underwent a further scan in 2004, whilst undergoing investigations on the other leg. This scan showed a 24 mm aneurysm of the proximal graft. This was asymptomatic. Surgery was considered but the patient had multiple medical comorbidities and conservative management was deemed the safest option. He remained asymptomatic and died in 2006 from an unrelated cause. Patient 4 This gentleman underwent the elective repair of a left popliteal aneurysm using reversed GSV in June 2004. No problems were identified on graft surveillance and he was discharged. He represented in 2010 with a pulsatile mass in his lower thigh and on ultrasound scanning, this was diagnosed as a 40 mm aneurysm of the proximal graft. The option of surgery was discussed with the patient but as he was currently asymptomatic, he declined and opted instead for continued surveillance. He has remained asymptomatic and surveillance scans have shown no increase in the size of the aneurysm. Of the patients who developed graft aneurysms, all had aneurysmal disease at other sites compared with 18 (45.0%) patients who did not develop graft aneurysms. All four patients who developed graft aneurysms had bilateral popliteal aneurysms and three (75%) of these patients had an AAA. The distributions of concomitant aneurysms are shown in Table 1. Patients with graft aneurysms had a mean of 1.60 aneurysms elsewhere compared to 0.58 in patients with non-aneurysmal grafts (P ¼ 0.005).
Discussion and conclusions
Patient 2 This gentleman underwent an emergency bypass of a left popliteal aneurysm using reversed GSV in October 2000 after presenting with a critical leg. He made a
True aneurysmal dilation of veins used for arterial bypass surgery is thought to be very rare. Most often, they are described in patients who have undergone CABG.2 Saphenous vein aneurysms after infrainguinal
Downloaded from vas.sagepub.com by guest on November 15, 2015
496
Vascular 23(5)
Table 1. Distribution of concomitant aneurysms. Type of aneurysm Aorto-iliac Contralateral popliteal Femoral
All patients
Graft aneurysm
No graft aneurysm
17 (37.7%) 12 (26.7%)
3 (75.0%) 4 (100.0%)
14 (35.0%) 8 (20.0%)
1 (2.2%)
0 (0.0%)
1 (2.5%)
bypass surgery are described rarely in the literature, almost exclusively in the form of isolated case reports or small case series.3,4 The first significant mention of the problem was Szilagy et al.5 in 1973, who identified aneurysmal dilation in 3.8% of femoropopliteal grafts. Two cases were reported in 1983.6 More recently, a number of cases have been reported3,4,7,8 which all described cases of isolated aneurysms developing in saphenous vein bypass grafts many years after they were performed for occlusive disease. These studies have all commented on the very low incidence of these vein graft aneurysms. However, patients with popliteal aneurysms are very likely to have aneurysms at other sites and the presumption therefore is that they are likely to have a genetic predisposition to the development of aneurysmal disease.9 We therefore speculated that these patients may also have a higher than average tendency to develop aneurysms in the grafts. Our data would seem to support this hypothesis. During our study period, 8.8% of patients have developed graft aneurysms. This is in contrast to other authors who have estimated the incidence to be well under 1%.6 It should also be noted that this was a retrospective study and patients were not routinely followed up for more than 18 months. Three out of the four patients with graft aneurysms were asymptomatic at presentation and their aneurysms were only discovered incidentally on scanning for other reasons. Therefore, it is not unreasonable to suggest that there may be more patients with aneurysms, which have not been identified. The pathogenesis of these aneurysms is unknown. Most authors have speculated that they are the result of progression of the atherosclerotic process.5,7 Other suggestions are that they result from trauma or from weakness at valve sites. However, a number of the cases described in the literature10,11 have been associated with aneurysmal disease at other sites. A recent paper12 described a 53 mm aneurysm developing four years after popliteal artery aneurysm repair. To our knowledge, this is the only previously reported case of an aneurysm developing in a saphenous vein graft following popliteal aneurysm repair. This patient also had a history of an AAA. The patients described in our report
have developed their aneurysms at a relatively early stage compared to the reports in the literature, which follow grafts performed for occlusive disease. We suggest, therefore, that the majority of graft aneurysms are in fact associated with a genetic predisposition to aneurysmal disease and as such much more common and indeed occur much earlier following aneurysm bypass than following bypass for occlusive disease. The genetics of aneurysm disease are incompletely understood. However, there is strong evidence suggesting that there is indeed a significant genetic component to the disease. A family history of AAA has been shown to be the second strongest risk factor for the development of the condition after smoking. Patients with a first degree relative with AAA have a 12-fold greater chance of developing the disease.13 Not only this but they tend to develop an aneurysm earlier than those without a family history.14 However, a single genetic defect responsible has not been identified and it is likely that the pathology is multifactorial, possibly with different combinations of genetic loci being responsible in different populations.15 A genetic predisposition would not only explain the familial associations described above but would also explain the propensity for patients to develop multiple aneurysms. In such patients, it would seem entirely reasonable to predict a higher rate of vein graft aneurysms than the general population. Vein walls contain less smooth muscle than do arteries and when exposed to the increased pressures of the arterial system are likely, in those with a genetic predisposition, to become aneurysmal over time. All patients presenting here were managed conservatively and only one of the four have thus far, to our knowledge, experienced complications as a result of their graft aneurysms. However, in three cases, the decision over whether or not to intervene was made somewhat simpler by the fact that the patient either declined surgery or was clearly medically unfit for surgery due to their medical comorbidities. The issue of follow up after bypass surgery is controversial. Currently, the policy in our department is for ultrasound surveillance of the graft for 18 months. It may be reasonable to extend the graft surveillance programme for patients following popliteal aneurysm bypass for longer than would be thought necessary for patients after infrainguinal bypass for occlusive disease. Indeed, it could be argued that these patients should have life-long graft surveillance. The primary limitation of our study is the lack of long-term prospective follow up. Patients were not routinely scanned for longer than 18 months postoperatively and therefore, we cannot claim to describe the true incidence of graft aneurysm after popliteal surgery. However, graft aneurysms have been perceived as
Downloaded from vas.sagepub.com by guest on November 15, 2015
Sharples et al.
497
a rare event following infrainguinal bypass surgery but have mainly been studied only in patients with occlusive disease. Our data would suggest the incidence might well be much higher in patients with a history of aneurysmal degeneration. More research is required to assess the true incidence of graft aneurysms in this patient group.
5.
6.
Conclusions True vein graft aneurysms occur in a significant number of patients following popliteal aneurysm repair. Our data would suggest this to be more likely in patients who have aneurysms at other sites and, therefore, probably a genetic predisposition to aneurysmal disease. It may be appropriate for patients with aneurysms at other sites to undergo more prolonged post-operative graft surveillance. Conflict of interest
7.
8.
9.
10.
The authors declare that there is no conflict of interest. 11.
Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
12.
References 1. Dent TL, Lindenauer SM, Ernst CB, et al. Multiple arteriosclerotic arterial aneurysms. Arch Surg 1972; 105: 338–344. 2. Kazui T, Harada H and Komatsu S. Saphenous vein aneurysm following coronary artery bypass grafting. J Cardiovasc Surg 1988; 29: 364–367. 3. Casha A, Holdsworth RJ, Stonebridge PA, et al. Infrainguinal saphenous vein graft aneurysm and aortic aneurysm. Eur J Vasc Endovasc Surg 1996; 12: 380–382. 4. Barker SGE, Hancock JH and Baskerville PA. True aneurysms of infrainguinal vein bypass grafts: the need for
13.
14.
15.
active, not passive management. Eur J Vasc Endovasc Surg 1996; 12: 378–379. Szilagyi DE, Elliott JP, Hageman JH, et al. Biological fate of autogenous vein implants as arterial substitutes: clinical, angiographic and histopathologic observations in femoropopliteal operations for atherosclerosis. Ann Surg 1973; 178: 232–246. Denton MJ, McCowan MA and Scott DF. True aneurysm formation in femoropopliteal autogenous vein bypass grafts: two cases. Aust N Z J Surg 1983; 53: 317–320. Kelly PH, Julsrud JM, Dyrud PE, et al. Aneurysmal rupture of a femoropopliteal saphenous vein graft. Surgery 1990; 107: 468–470. Bohra AK, Doyle T and Harvey C. True aneurysm of a femoropopliteal vein graft. Int J Clin Pract 2001; 55: 725–726. Diwan A, Sarkar R, Stanley JC, et al. Incidence of femoral and popliteal artery aneurysms in patients with abdominal aortic aneurysms. J Vasc Surg 2000; 31: 863–869. Peer RM and Upson JF. Aneurysmal dilatation in saphenous vein bypass grafts. J Cardiovasc Surg 1990; 31: 668–671. De La Rocha AG, Peixoto RS and Baird RJ. Atherosclerosis and aneurysm formation in a saphenous vein graft. Br J Surg 1973; 60: 72–73. Lopez MT, Dorgham AS, Rosas FC, et al. Aneurysmal degeneration of a saphenous vein graft following the repair of a popliteal aneurysm: case report and literature review. Vascular 2012; 20: 294–298. Johansen K and Koepsell T. Familial tendency for abdominal aortic aneurysms. JAMA 1986; 256: 1934–1936. Kuivaniemi H, Shibamura H, Arthur C, et al. Familial abdominal aortic aneurysms: collection of 233 multiplex families. J Vasc Surg 2003; 37: 340–345. Saratzis A and Bown MJ. The genetic basis for aortic aneurysmal disease. Heart 2014; 100: 916–922.
Downloaded from vas.sagepub.com by guest on November 15, 2015
Vein graft aneurysms following popliteal aneurysm repair are more common than we think
Vascular 2015, Vol. 23(5) 494–497 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1708538114557070 vas.sagepub.com
Alistair Sharples, Mark Kay, Timothy Sykes, Anthony Fox and Andrew Houghton
Abstract True infrainguinal vein graft aneurysms are reported infrequently in the literature. We sought to identify the true incidence of these graft aneurysms after popliteal aneurysm repair and identify factors which may increase the risk of such aneurysms developing. Using a prospectively compiled database, we identified patients who underwent a popliteal aneurysm repair between January 1996 and January 2011 at a single district general hospital. Patients were routinely followed up in a graft surveillance programme. Out of 45 patients requiring repair of a popliteal aneurysm over a 15-year period, four (8.8%) patients developed aneurysmal graft disease. Of the patients who developed graft aneurysms, all had aneurysmal disease at other sites compared with 18 (45.0%) patients who did not develop graft aneurysms. Patients with graft aneurysms had a mean of 1.60 aneurysms elsewhere compared to 0.58 in patients with non-aneurysmal grafts (P ¼ 0.005). True vein graft aneurysms occur in a significant number of patients following popliteal aneurysm repair. Our data would suggest this to be more likely in patients who have aneurysms elsewhere and therefore a predisposition to aneurysmal disease. It may be appropriate for patients with aneurysms at other sites to undergo more prolonged postoperative graft surveillance.
Keywords Aneurysmal disease, popliteal aneurysm
Introduction
Materials and methods
Popliteal aneurysms are the most common peripheral aneurysm. They typically affect middle-aged men. It is generally accepted that there is a genetic aspect to aneurysmal disease. Popliteal aneurysms are commonly associated with aneurysms at other locations. Forty percent of patients with a popliteal aneurysm will have an abdominal aortic aneurysm (AAA) and 50% will have bilateral popliteal aneurysms.1 True saphenous vein aneurysms after coronary artery bypass grafting (CABG) are uncommon but well documented.2 However, despite the widespread use of the saphenous vein as the favoured conduit for infrainguinal bypass surgery relatively little has been written on infrainguinal vein graft aneurysms. Below we describe our experiences of saphenous vein graft aneurysms in patients undergoing exclusion of a popliteal aneurysm.
We retrospectively examined 45 patients who underwent exclusion of a popliteal aneurysm using saphenous vein between January 1999 and December 2006. All the procedures were performed by or under the immediate supervision of one of three experienced vascular consultants. Information for analysis was obtained from two sources: from a prospectively collated departmental vascular database and from the patients’ case notes. All the procedures were performed from a medial approach with ligation of the native popliteal artery Vascular Surgery Department, Royal Shrewsbury Hospital, Shrewsbury, UK Corresponding author: Alistair Sharples, Royal Shrewsbury Hospital, Mytton Oak Road, Shrewsbury SY3 8XQ, UK. Email: [email protected]
Downloaded from vas.sagepub.com by guest on November 15, 2015
Sharples et al.
495
and reversed saphenous vein bypass. Patients underwent pre-operative vein scanning to assess the quality of their veins. Veins were deemed suitable if they were of a diameter of greater than 2 mm with no evidence of venous incompetence. In addition, veins were inspected intra-operatively by the operating surgeon. Patients who underwent popliteal aneurysm surgery using other techniques or other types of graft material were excluded from the analysis. Both elective and emergency procedures are included. Preoperatively, all patients underwent imaging of their aorta and lower limb arteries and the presence of any other aneurysms was recorded. Patients underwent duplex graft surveillance scans at 6 weeks, 6, 12, 18 months and based on clinical need thereafter.
Results Forty-five patients underwent exclusion bypass for a popliteal artery aneurysm using a long saphenous vein graft. Forty-four (97.8%) patients were male. The mean age was 71 years. Four (8.8%) patients developed aneurysmal graft disease. All had true aneurysms within the body of the graft. Two underwent elective and two emergency bypass procedures. Only one of the aneurysms was found during the period of graft surveillance with the others discovered during imaging for other reasons. The four cases are presented below. Patient 1 This gentleman was admitted as an emergency with right critical limb ischaemia. Clinically he had a popliteal aneurysm, which had embolised to all the distal vessels. He underwent a bypass using reversed great saphenous vein (GSV). This graft failed two months later and required revision using cephalic vein. Two years later this graft again failed and was revised using GSV from the calf. Eight months later at routine graft surveillance a 15 mm aneurysm was noted in the main body of the vein graft. This was followed up for two years and remained stable and asymptomatic. The patient was then lost to follow up until he represented in 2008 with a critically ischaemic right-leg but with a patent graft. This was likely secondary to embolisation from this aneurysm. Due to poor general health, this was managed conservatively and he died in 2009 from unrelated causes.
good post-operative recovery and 18 months of graft surveillance was completed with no concerns and he was discharged. He represented in 2005 with a nonhealing ulcer on his left ankle. He underwent further ultrasound examination of his graft, which demonstrated there to be two aneurysms of the graft, one at the proximal end measuring 20 mm and one distally, which measured 18 mm. He was managed conservatively and remains asymptomatic. Patient 3 This gentleman had elective repair of a right popliteal aneurysm using reversed GSV in March 2001. He completed the graft surveillance programme with no complications identified. He underwent a further scan in 2004, whilst undergoing investigations on the other leg. This scan showed a 24 mm aneurysm of the proximal graft. This was asymptomatic. Surgery was considered but the patient had multiple medical comorbidities and conservative management was deemed the safest option. He remained asymptomatic and died in 2006 from an unrelated cause. Patient 4 This gentleman underwent the elective repair of a left popliteal aneurysm using reversed GSV in June 2004. No problems were identified on graft surveillance and he was discharged. He represented in 2010 with a pulsatile mass in his lower thigh and on ultrasound scanning, this was diagnosed as a 40 mm aneurysm of the proximal graft. The option of surgery was discussed with the patient but as he was currently asymptomatic, he declined and opted instead for continued surveillance. He has remained asymptomatic and surveillance scans have shown no increase in the size of the aneurysm. Of the patients who developed graft aneurysms, all had aneurysmal disease at other sites compared with 18 (45.0%) patients who did not develop graft aneurysms. All four patients who developed graft aneurysms had bilateral popliteal aneurysms and three (75%) of these patients had an AAA. The distributions of concomitant aneurysms are shown in Table 1. Patients with graft aneurysms had a mean of 1.60 aneurysms elsewhere compared to 0.58 in patients with non-aneurysmal grafts (P ¼ 0.005).
Discussion and conclusions
Patient 2 This gentleman underwent an emergency bypass of a left popliteal aneurysm using reversed GSV in October 2000 after presenting with a critical leg. He made a
True aneurysmal dilation of veins used for arterial bypass surgery is thought to be very rare. Most often, they are described in patients who have undergone CABG.2 Saphenous vein aneurysms after infrainguinal
Downloaded from vas.sagepub.com by guest on November 15, 2015
496
Vascular 23(5)
Table 1. Distribution of concomitant aneurysms. Type of aneurysm Aorto-iliac Contralateral popliteal Femoral
All patients
Graft aneurysm
No graft aneurysm
17 (37.7%) 12 (26.7%)
3 (75.0%) 4 (100.0%)
14 (35.0%) 8 (20.0%)
1 (2.2%)
0 (0.0%)
1 (2.5%)
bypass surgery are described rarely in the literature, almost exclusively in the form of isolated case reports or small case series.3,4 The first significant mention of the problem was Szilagy et al.5 in 1973, who identified aneurysmal dilation in 3.8% of femoropopliteal grafts. Two cases were reported in 1983.6 More recently, a number of cases have been reported3,4,7,8 which all described cases of isolated aneurysms developing in saphenous vein bypass grafts many years after they were performed for occlusive disease. These studies have all commented on the very low incidence of these vein graft aneurysms. However, patients with popliteal aneurysms are very likely to have aneurysms at other sites and the presumption therefore is that they are likely to have a genetic predisposition to the development of aneurysmal disease.9 We therefore speculated that these patients may also have a higher than average tendency to develop aneurysms in the grafts. Our data would seem to support this hypothesis. During our study period, 8.8% of patients have developed graft aneurysms. This is in contrast to other authors who have estimated the incidence to be well under 1%.6 It should also be noted that this was a retrospective study and patients were not routinely followed up for more than 18 months. Three out of the four patients with graft aneurysms were asymptomatic at presentation and their aneurysms were only discovered incidentally on scanning for other reasons. Therefore, it is not unreasonable to suggest that there may be more patients with aneurysms, which have not been identified. The pathogenesis of these aneurysms is unknown. Most authors have speculated that they are the result of progression of the atherosclerotic process.5,7 Other suggestions are that they result from trauma or from weakness at valve sites. However, a number of the cases described in the literature10,11 have been associated with aneurysmal disease at other sites. A recent paper12 described a 53 mm aneurysm developing four years after popliteal artery aneurysm repair. To our knowledge, this is the only previously reported case of an aneurysm developing in a saphenous vein graft following popliteal aneurysm repair. This patient also had a history of an AAA. The patients described in our report
have developed their aneurysms at a relatively early stage compared to the reports in the literature, which follow grafts performed for occlusive disease. We suggest, therefore, that the majority of graft aneurysms are in fact associated with a genetic predisposition to aneurysmal disease and as such much more common and indeed occur much earlier following aneurysm bypass than following bypass for occlusive disease. The genetics of aneurysm disease are incompletely understood. However, there is strong evidence suggesting that there is indeed a significant genetic component to the disease. A family history of AAA has been shown to be the second strongest risk factor for the development of the condition after smoking. Patients with a first degree relative with AAA have a 12-fold greater chance of developing the disease.13 Not only this but they tend to develop an aneurysm earlier than those without a family history.14 However, a single genetic defect responsible has not been identified and it is likely that the pathology is multifactorial, possibly with different combinations of genetic loci being responsible in different populations.15 A genetic predisposition would not only explain the familial associations described above but would also explain the propensity for patients to develop multiple aneurysms. In such patients, it would seem entirely reasonable to predict a higher rate of vein graft aneurysms than the general population. Vein walls contain less smooth muscle than do arteries and when exposed to the increased pressures of the arterial system are likely, in those with a genetic predisposition, to become aneurysmal over time. All patients presenting here were managed conservatively and only one of the four have thus far, to our knowledge, experienced complications as a result of their graft aneurysms. However, in three cases, the decision over whether or not to intervene was made somewhat simpler by the fact that the patient either declined surgery or was clearly medically unfit for surgery due to their medical comorbidities. The issue of follow up after bypass surgery is controversial. Currently, the policy in our department is for ultrasound surveillance of the graft for 18 months. It may be reasonable to extend the graft surveillance programme for patients following popliteal aneurysm bypass for longer than would be thought necessary for patients after infrainguinal bypass for occlusive disease. Indeed, it could be argued that these patients should have life-long graft surveillance. The primary limitation of our study is the lack of long-term prospective follow up. Patients were not routinely scanned for longer than 18 months postoperatively and therefore, we cannot claim to describe the true incidence of graft aneurysm after popliteal surgery. However, graft aneurysms have been perceived as
Downloaded from vas.sagepub.com by guest on November 15, 2015
Sharples et al.
497
a rare event following infrainguinal bypass surgery but have mainly been studied only in patients with occlusive disease. Our data would suggest the incidence might well be much higher in patients with a history of aneurysmal degeneration. More research is required to assess the true incidence of graft aneurysms in this patient group.
5.
6.
Conclusions True vein graft aneurysms occur in a significant number of patients following popliteal aneurysm repair. Our data would suggest this to be more likely in patients who have aneurysms at other sites and, therefore, probably a genetic predisposition to aneurysmal disease. It may be appropriate for patients with aneurysms at other sites to undergo more prolonged post-operative graft surveillance. Conflict of interest
7.
8.
9.
10.
The authors declare that there is no conflict of interest. 11.
Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
12.
References 1. Dent TL, Lindenauer SM, Ernst CB, et al. Multiple arteriosclerotic arterial aneurysms. Arch Surg 1972; 105: 338–344. 2. Kazui T, Harada H and Komatsu S. Saphenous vein aneurysm following coronary artery bypass grafting. J Cardiovasc Surg 1988; 29: 364–367. 3. Casha A, Holdsworth RJ, Stonebridge PA, et al. Infrainguinal saphenous vein graft aneurysm and aortic aneurysm. Eur J Vasc Endovasc Surg 1996; 12: 380–382. 4. Barker SGE, Hancock JH and Baskerville PA. True aneurysms of infrainguinal vein bypass grafts: the need for
13.
14.
15.
active, not passive management. Eur J Vasc Endovasc Surg 1996; 12: 378–379. Szilagyi DE, Elliott JP, Hageman JH, et al. Biological fate of autogenous vein implants as arterial substitutes: clinical, angiographic and histopathologic observations in femoropopliteal operations for atherosclerosis. Ann Surg 1973; 178: 232–246. Denton MJ, McCowan MA and Scott DF. True aneurysm formation in femoropopliteal autogenous vein bypass grafts: two cases. Aust N Z J Surg 1983; 53: 317–320. Kelly PH, Julsrud JM, Dyrud PE, et al. Aneurysmal rupture of a femoropopliteal saphenous vein graft. Surgery 1990; 107: 468–470. Bohra AK, Doyle T and Harvey C. True aneurysm of a femoropopliteal vein graft. Int J Clin Pract 2001; 55: 725–726. Diwan A, Sarkar R, Stanley JC, et al. Incidence of femoral and popliteal artery aneurysms in patients with abdominal aortic aneurysms. J Vasc Surg 2000; 31: 863–869. Peer RM and Upson JF. Aneurysmal dilatation in saphenous vein bypass grafts. J Cardiovasc Surg 1990; 31: 668–671. De La Rocha AG, Peixoto RS and Baird RJ. Atherosclerosis and aneurysm formation in a saphenous vein graft. Br J Surg 1973; 60: 72–73. Lopez MT, Dorgham AS, Rosas FC, et al. Aneurysmal degeneration of a saphenous vein graft following the repair of a popliteal aneurysm: case report and literature review. Vascular 2012; 20: 294–298. Johansen K and Koepsell T. Familial tendency for abdominal aortic aneurysms. JAMA 1986; 256: 1934–1936. Kuivaniemi H, Shibamura H, Arthur C, et al. Familial abdominal aortic aneurysms: collection of 233 multiplex families. J Vasc Surg 2003; 37: 340–345. Saratzis A and Bown MJ. The genetic basis for aortic aneurysmal disease. Heart 2014; 100: 916–922.
Downloaded from vas.sagepub.com by guest on November 15, 2015
