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Initial experience with the polytetrafluoroethylene graft for limb salvage
Initial Experience with the Polytetrafluoroethylene Graft for Limb Salvage A Report on Twenty Patients P. D. Fry, MD, Vancouver, British Columbia M. E. Robertson, BSc, Vancouver, British Columbia
Although polytetrafluoroethylene (PTFE) grafts have been marketed for a short period of time, data on their use are rapidly accumulating in the literature. It is generally concluded that for salvage procedures in the lower limb, autogenous vein provides the most successful results. Many patients with impending limb loss, however, may no longer possess suitable veins for this purpose. By the same token, it is clear that limbs are lost not necessarily because of progression of disease but often because of the absence of a suitable arterial conduit. The introduction of PTFE, a unique synthetic material which may be used for interposition or bypass grafting, has permitted successful arterial reconstruction in the lower limb. This graft may be placed across joints and can be used in clinical situations in which arterial runoff is compromised. Our recent experience with PTFE grafts in twenty patients undergoing limb salvage procedures is documented herein. Material and Methods The present study analyzes the results of reconstructive arterial bypass surgery using PTFE (Goretex, Gore and Associates, Flagstaff, CA) grafts in twenty patients (Table I) at the Vancouver General Hospital who were faced with impending limb loss associated with either severe rest pain (13 patients) or frank gangrene (7 patients). Not included were patients with claudication in whom we used PTFE From the Department of .Sw@ry, Diagnostic Vascular Laboratwy. uliversity of Sritish Columbia, Vancouver General Hospital, Vancouver, British Columbia. Reprint requests should be addressed to P. D. Fry, MD, Department of Surgery, 700 West Tenth Avenue, Vancouver, British Columbia V5Z lL5, Canada. Presented at tha Sixth Annual Meeting of the Society fw Clinical Vascular Surgery, Palm Springs, California, April 1-5. 1978.
Volume 136, August 1978
grafts or patients with the same presentation as the reported group in whom PTFE grafts were placed in only extraanatomic positions for limb salvage. Gangrene was limited in each case to a digit or ischemic ulcer. There were seventeen males (mean age, 62 years) and three females (mean age, 72 years). Femoral arteriography was performed prior to or during surgery in nineteen patients, whereas one patient underwent bypass without benefit of arteriography. The number of patent runoff vessels was documented with particular reference to the existence of a dominant artery in the runoff system and the presence of distal disease. The graft size in each case was noted as well as previous bypass operations in the same limb. The number of grafts remaining patent was recorded at the time of discharge and during the follow-up period. In each case the saphenous vein had been used for a previous bypass, was absent, or was unsuitable for use. Standard exposure of the femoral, popliteal, and tibial vessels was used in sixteen patients, whereas in the remaining four a lateral approach to the anterior tibia1 or peroneal artery by a subperiosteal resection of the fibula was employed [I]. In one patient a bypass was performed from the left common femoral artery across the pubis to the peroneal artery via a lateral approach. Another patient underwent an extraanatomic bypass to improve the inflow in the affected limb as well as a long limb bypass. Sympathectomy was performed in conjunction with salvage procedures in only two patients. Results
In seven patients presenting with frank gangrene and in whom arterial bypass was performed, six grafts were patent at discharge and five remained patent for a mean of 13.6 months. Two have occluded. Limb loss occurred in only one patient. Results were similar in the thirteen patients in whom the indication for bypass was rest pain. Twelve grafts
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Fty and Robertson
TABLE I
Clinical Data
Age (yr)
Runoff Vessels
vs GF GF BM HR RL JM CB
73 57 58 54 64
& JB JP JC
:9” 84 69 50 49 74 65
1D 1D 1D 2 2 3 1 2 2 1D 3 2 3 2 1D 1D 3
Patient
z: HO OS WJ VM TV
I: 40
8% 57 89
x 2
Graft Sk0 (mm)
Previous Failed Graft
Reason for Bypass
T T T 6 T 8 8 6 6 T T T T T T T 6 6 6 6
FPX 2(BK) FP (V) FP (V) FP
G RP RP RP G RP RP RP RP RP G G RP RP RP
FP X 2 FPer
FP FP FP
: G RP RP
FP
site for Bypass FAT FPT FPer FP (AK) FCT FP (AK) FAT FPT FP (BK) FPer FPT FPT FCT FP (AK) FAT FPer FP (BK) FP (AK) FP (BK) FP (BK)
Patency at Discharge
Patent
P P P P P P
14 13 11 18 3 18
P P P
13 11 15
P P P P P P P P P
20 0 5 13 15 9 7 10 9
MO
Limb Salvage Yes Yes Yes Yes Yes Yes No Yes Yes Yes No Yes No Yes Yes Yes Yes Yes Yes Yes
Amputatlon
Digit BK
AK Digit AK
Digit BK
Note: D = dominant; Fq = femoropopliteal; G = gangrene; RP = rest pain; FAT = femoral-anterior tibial; FPT = femoral-posterior tibial; FPer = femoroperoneal; AK = above-knee; BK = below-knee; P = patent.
were patent at discharge, nine are currently patent (mean, 13.2 months), and of four patients who had occluded grafts, three lost the limb despite sympathectomy. Of the six grafts that occluded (Table II), three did so in the immediate postoperative period, and the limbs were amputated. Three of these six patients had previously undergone bypass procedures for limb salvage. Two presented with gangrene and four with rest pain. Three grafts remained patent for a mean of ten months. The number of vessels patent in the runoff system bore no relationship to graft failure, although the degree of disease in the patent vessel did. Ten of twenty patients in the study had received one or more grafts in the past (Table III), two for limb
salvage. Two now presented with gangrene and eight with rest pain. Seven of the ten went on to successful limb salvage and currently have patent grafts, with a mean patency of 13.4 months. Three patients in this group required amputation when their grafts occluded. Two of the three underwent immediate occlusion in the operating room while one graft remained patent for three months before occluding. An effort was made to assess the cause of failure in each of the original bypass procedures. No dominant cause could be identified, but in several cases it was clearly related to our bypassing into diseased vessels rather than crossing the joint into disease-free arteries because of our reluctance to cross the joint with a Dacron@ graft or to perform a composite graft procedure. Comments
TABLE II
Profile of Patients with Failed PlFE Grafts
Patlent
Clinical Presentation
HR JM JB JC RA TV
G RP G RP RP RP
Previous Graft FP FP FP
Runoff Vessels
Llmb Loss
Mo Patent
2’ 1’ 3 3’ 2 2’
Digit BK AK AK
10 0 0 0 12 9
BK,
Note: G = gangrene: RP = rest pain; FP = femoropopliteal; BK = below-knee; AK = above-knee. Vessels patent but diseased. l
194
The morphologic qualities and characteristics of PTFE for bypass surgery have been well described by other authors [Z-5] and will not be reiterated herein. Although only the initial results of clinical experience with PTFE are currently available, its use for interposition or bypass grafting in large or medium sized vessels suggests that it is at least as good as other synthetic grafts. It is unique in that it can be placed across joints where other synthetic materials are not as successful.
The Amwlcan Journal d &gory
PTFE Graft
TABLE
_--
III
PTFE Grafts in Patients with Prevlously Failed Grafts
Patient JS GF GF BM JM CM JB JC GB VM
Anastomotic Sites
Indications
FP X 2 (BK) FP FP FP FP X 2 FPer FP FP FP FP
G RP RP RP RP RP G RP RP RP
New Graft
MO
Patency at Discharge
Patent
P P P P
14 13 11 18
P
13
P P P
3 13 11
FAT FPT FPer FP (AK) FAT FPT FP FCT FAT FP (BK)
Amputation
BK AK AK
Note: FP = femoropopliteal; FPer = femoroperoneal; G = gangrene: RP = rest pain; FAT = femoral-antarkx tibiil; FPT = femorai-posterkx tibiat; P = patent; BK = below-knee; AK = above-knee.
Sauvage et al [5], in comparing different graft fabrics, described PTFE as fulfilling four of five criteria for an ideal synthetic graft. These qualities provide a versatility and durability not found in other synthetic grafts. The characteristic graft structure allowing full heparinization without the need to preclot the graft obviously bestows a significant advantage. Because the spectrum of disease is so variable, it is difficult to compare the results of different forms of grafting material in limb salvage procedures. There are a number of reasons for this. The natural history of atherosclerosis associated with an ischemic limb is such that patient survival is frequently measured in months rather than years. Our assessment of the extent of disease and our decision to bypass a particular limb in terms of the quality of distal runoff as demonstrated by monoplane arteriography is primarily subjective even in the presence of Dopplerassessed calf pressures. The experience of the surgeon, his technical ability, and his philosophy regarding limb salvage are all qualities that fail to lend themselves readily to objective analysis. Nevertheless, they frequently influence the outcome of the procedure. Therefore, to compare patients in terms of the number of patent distal vessels is a fruitless exercise where quality of the runoff is so much more important. Clearly, one of the main advantages of the PTFE graft over other synthetic grafts is that it can be used effectively across the knee ioint and into small arteries, provided.the runoff is adequate. Ease of handling and resistance to infection [3] are further advantages.
In some centers, limb salvage has become an emotional issue with those who believe that amputation and rehabilitation represent the most expeditious means of mobilizing patients versus others who believe that almost anything is justified in pre-
Volume 136, August 1979
venting limb loss. It is undisputedly true that many patients in whom limb salvage or rehabilitation fail will be converted from an independent to an institutionalized state. While this facet must be kept in perspective, the answer probably lies somewhere between these two philosophies. The approach at Vancouver General Hospital toward limb salvage is moderately aggressive. Long limb PTFE bypasses sometimes coupled with extraanatomic grafts to improve arterial inflow have been used in limb salvage attempts usually with gratifying results. Concomitant use of heparin and low molecular weight dextran in the first 48 hours postoperatively may aid patency. Although our overall graft patency rate was 70 per cent (mean follow-up, 13.2 months), as indicated by palpable pulses or increased ankle pressures, our limb salvage rate was 80 per cent (16 of 20 patients) over this period. These figures approximate those of Campbell et al [2] who achieved 87 per cent limb salvage in fifteen patients, one of whom had a long bypass. However, in the present series, there were twelve limbs in which long bypasses were performed.
TABLE IV
Patient HO EB GS GF
GF vs
PTFE Bypass Into Single Domlnant Vessels Indications
Anastomotic Sites
Patency at Discharge
G RP RP RP RP G
FPer FAT FPer FPT FPT FAT
P P P P P P
MO
Patent
Salvage
15 Yes 13 Yes 15 Yes 13 Yes 11 Yes 14 Yes mean: 13.50
Note: G = gangrene; RP = rest pain; FPer = femoroperoneal: FAT = femoral-anterior tibial; FPT = femoral-posterior tibial; P =
patent.
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Fry and Robertson
Figure 7. HO, a sixty-five year old male, with single dominant peroneal vessel supplying the leg demonstrated preopefatlvely.
There were six patients (Table IV) in whom long bypasses were placed into single dominant vessels below the knee. (Figures 1 and 2.) On each occasion, monoplane arteriography demonstrated the single vessel to be relatively free of atherosclerosis. Currently, all six patients have patent grafts (mean, 13.5 months), and limb salvage has been achieved. In these patients, a 6.5 to 4.5 mm tapered graft was used. The small number of patients involved prevents any conclusions from being drawn regarding graft position and patency. (Table V.) The fact that the three peroneal bypass grafts and five of seven anterior and posterior tibia1 grafts remained patent reflects the choice of bypass into a single dominant vessel but illustrates that these grafts do well in below-knee positions. This aspect is further demonstrated when assessment of patency in terms of the number of runoff vessels is made. (Table VI.) Here it is evident that the greatest patency rates were achieved where bypass was performed into a single large dominant below-knee vessel. Where double and triple runoff was found, the failure rate approached 50 per cent, because although patency was apparent on monoplane arteriograms, the arteries were often discovered at surgery to be diseased. Analysis of the initial results demonstrates that while the long-term patency of the PTFE graft is as yet unknown, it is suitable for long bypass procedures
196
F/gore 2. Same patlent as In Figure 1 postoperatively, wfth PTFE bypass Into peroneal artery via a lateral approach with resect/on of the flbula.
in the lower limb. The early patency rate at six months where there is adequate distal runoff is 75 per cent. Late failures reduce the patency rate at one year to 70 per cent and appear to be related to the progression of distal disease rather than to mechanical difficulties with the graft itself. Therefore, the PTFE graft seems eminently suitable for bypass or interposition procedures in the absence of a suitable vein,
The American Journal of Surgery
F’TFE Graft
TABLE V
Results of Salvage Procedures in Relation to Graft Position
Position ___--_------.
No. of Grafts
Thrombosis
Amputation
FP (AK) FP (BK) F”T F4T -- F?er
4 6 4 3 3
2 3 1 1 0
1 2 1 1 0
Mean Patency (mo) 17.0 8.16 15.0 13.5 13.5
Note: FP = femoropopliteal; AK = above-knee; BK = belowknee; FPT = femoral-posterior tibial; FAT = femoral-anterior tibial; FPer = femoroperoneal.
Summary
The early results of the bypass procedures for limb salvage using the new polytetrafluoroethylene (PTFE) graft are analyzed. Of twenty patients presenting with either severe rest pain or gangrene, patency has been maintained in fourteen for a mean period of thirteen months to date. Particularly satisfying results have been achieved when bypassing into single dominant arteries below the knee where limb salvage and graft patency was obtained in all cases.
Volume 138, August 1978
TABLE VI No. of - Patients 1 6 9 4
PTFE Graft Patency versus Number of Patent Vessels Runoff Vessels ----_ Single, diseased Single, dominant Double Triple
MO Patency at .___________ Discharge Patent
--._
n 6 6 2 _-_.
0 13.5 12.2 6.25
References 1. Dardik H, Dardik I, Veith FJ: Exposure of the tibial-peroneal arteries by a single lateral approach. Surgery 75: 377. 1974. 2. Campbell CD, Brooks DH, Webster MW, Bahnson HT: Use of expanded microporous polytetrafluoroethylene for limb salvage: a preliminary report. Surgery 79: 485, 1976. 3. Kaplan MS, Mirahmadi MD, Weiner R. Gorman JT: Resistance of PTFE grafts to early or late infections. Presented at the Seventh Annual Meeting of the Western Dialysis and Transplant Society, Seattle, Washington, October 1976. 4. Matsumoto H, Hasegawa T, Fuse K, Yamamoto M, Saigusa M: A new vascular prosthesis for a small caliber artery. Surgery 74: 519, 1973. 5. Sauvage LR, Berger KE, Mansfield PB, Wood SJ, Smith JC, Overton JB: Future directions in the development of arterial prostheses for small and medium caliber arteries. Surg C/in North Am54: 213, 1974.
197
Although polytetrafluoroethylene (PTFE) grafts have been marketed for a short period of time, data on their use are rapidly accumulating in the literature. It is generally concluded that for salvage procedures in the lower limb, autogenous vein provides the most successful results. Many patients with impending limb loss, however, may no longer possess suitable veins for this purpose. By the same token, it is clear that limbs are lost not necessarily because of progression of disease but often because of the absence of a suitable arterial conduit. The introduction of PTFE, a unique synthetic material which may be used for interposition or bypass grafting, has permitted successful arterial reconstruction in the lower limb. This graft may be placed across joints and can be used in clinical situations in which arterial runoff is compromised. Our recent experience with PTFE grafts in twenty patients undergoing limb salvage procedures is documented herein. Material and Methods The present study analyzes the results of reconstructive arterial bypass surgery using PTFE (Goretex, Gore and Associates, Flagstaff, CA) grafts in twenty patients (Table I) at the Vancouver General Hospital who were faced with impending limb loss associated with either severe rest pain (13 patients) or frank gangrene (7 patients). Not included were patients with claudication in whom we used PTFE From the Department of .Sw@ry, Diagnostic Vascular Laboratwy. uliversity of Sritish Columbia, Vancouver General Hospital, Vancouver, British Columbia. Reprint requests should be addressed to P. D. Fry, MD, Department of Surgery, 700 West Tenth Avenue, Vancouver, British Columbia V5Z lL5, Canada. Presented at tha Sixth Annual Meeting of the Society fw Clinical Vascular Surgery, Palm Springs, California, April 1-5. 1978.
Volume 136, August 1978
grafts or patients with the same presentation as the reported group in whom PTFE grafts were placed in only extraanatomic positions for limb salvage. Gangrene was limited in each case to a digit or ischemic ulcer. There were seventeen males (mean age, 62 years) and three females (mean age, 72 years). Femoral arteriography was performed prior to or during surgery in nineteen patients, whereas one patient underwent bypass without benefit of arteriography. The number of patent runoff vessels was documented with particular reference to the existence of a dominant artery in the runoff system and the presence of distal disease. The graft size in each case was noted as well as previous bypass operations in the same limb. The number of grafts remaining patent was recorded at the time of discharge and during the follow-up period. In each case the saphenous vein had been used for a previous bypass, was absent, or was unsuitable for use. Standard exposure of the femoral, popliteal, and tibial vessels was used in sixteen patients, whereas in the remaining four a lateral approach to the anterior tibia1 or peroneal artery by a subperiosteal resection of the fibula was employed [I]. In one patient a bypass was performed from the left common femoral artery across the pubis to the peroneal artery via a lateral approach. Another patient underwent an extraanatomic bypass to improve the inflow in the affected limb as well as a long limb bypass. Sympathectomy was performed in conjunction with salvage procedures in only two patients. Results
In seven patients presenting with frank gangrene and in whom arterial bypass was performed, six grafts were patent at discharge and five remained patent for a mean of 13.6 months. Two have occluded. Limb loss occurred in only one patient. Results were similar in the thirteen patients in whom the indication for bypass was rest pain. Twelve grafts
193
Fty and Robertson
TABLE I
Clinical Data
Age (yr)
Runoff Vessels
vs GF GF BM HR RL JM CB
73 57 58 54 64
& JB JP JC
:9” 84 69 50 49 74 65
1D 1D 1D 2 2 3 1 2 2 1D 3 2 3 2 1D 1D 3
Patient
z: HO OS WJ VM TV
I: 40
8% 57 89
x 2
Graft Sk0 (mm)
Previous Failed Graft
Reason for Bypass
T T T 6 T 8 8 6 6 T T T T T T T 6 6 6 6
FPX 2(BK) FP (V) FP (V) FP
G RP RP RP G RP RP RP RP RP G G RP RP RP
FP X 2 FPer
FP FP FP
: G RP RP
FP
site for Bypass FAT FPT FPer FP (AK) FCT FP (AK) FAT FPT FP (BK) FPer FPT FPT FCT FP (AK) FAT FPer FP (BK) FP (AK) FP (BK) FP (BK)
Patency at Discharge
Patent
P P P P P P
14 13 11 18 3 18
P P P
13 11 15
P P P P P P P P P
20 0 5 13 15 9 7 10 9
MO
Limb Salvage Yes Yes Yes Yes Yes Yes No Yes Yes Yes No Yes No Yes Yes Yes Yes Yes Yes Yes
Amputatlon
Digit BK
AK Digit AK
Digit BK
Note: D = dominant; Fq = femoropopliteal; G = gangrene; RP = rest pain; FAT = femoral-anterior tibial; FPT = femoral-posterior tibial; FPer = femoroperoneal; AK = above-knee; BK = below-knee; P = patent.
were patent at discharge, nine are currently patent (mean, 13.2 months), and of four patients who had occluded grafts, three lost the limb despite sympathectomy. Of the six grafts that occluded (Table II), three did so in the immediate postoperative period, and the limbs were amputated. Three of these six patients had previously undergone bypass procedures for limb salvage. Two presented with gangrene and four with rest pain. Three grafts remained patent for a mean of ten months. The number of vessels patent in the runoff system bore no relationship to graft failure, although the degree of disease in the patent vessel did. Ten of twenty patients in the study had received one or more grafts in the past (Table III), two for limb
salvage. Two now presented with gangrene and eight with rest pain. Seven of the ten went on to successful limb salvage and currently have patent grafts, with a mean patency of 13.4 months. Three patients in this group required amputation when their grafts occluded. Two of the three underwent immediate occlusion in the operating room while one graft remained patent for three months before occluding. An effort was made to assess the cause of failure in each of the original bypass procedures. No dominant cause could be identified, but in several cases it was clearly related to our bypassing into diseased vessels rather than crossing the joint into disease-free arteries because of our reluctance to cross the joint with a Dacron@ graft or to perform a composite graft procedure. Comments
TABLE II
Profile of Patients with Failed PlFE Grafts
Patlent
Clinical Presentation
HR JM JB JC RA TV
G RP G RP RP RP
Previous Graft FP FP FP
Runoff Vessels
Llmb Loss
Mo Patent
2’ 1’ 3 3’ 2 2’
Digit BK AK AK
10 0 0 0 12 9
BK,
Note: G = gangrene: RP = rest pain; FP = femoropopliteal; BK = below-knee; AK = above-knee. Vessels patent but diseased. l
194
The morphologic qualities and characteristics of PTFE for bypass surgery have been well described by other authors [Z-5] and will not be reiterated herein. Although only the initial results of clinical experience with PTFE are currently available, its use for interposition or bypass grafting in large or medium sized vessels suggests that it is at least as good as other synthetic grafts. It is unique in that it can be placed across joints where other synthetic materials are not as successful.
The Amwlcan Journal d &gory
PTFE Graft
TABLE
_--
III
PTFE Grafts in Patients with Prevlously Failed Grafts
Patient JS GF GF BM JM CM JB JC GB VM
Anastomotic Sites
Indications
FP X 2 (BK) FP FP FP FP X 2 FPer FP FP FP FP
G RP RP RP RP RP G RP RP RP
New Graft
MO
Patency at Discharge
Patent
P P P P
14 13 11 18
P
13
P P P
3 13 11
FAT FPT FPer FP (AK) FAT FPT FP FCT FAT FP (BK)
Amputation
BK AK AK
Note: FP = femoropopliteal; FPer = femoroperoneal; G = gangrene: RP = rest pain; FAT = femoral-antarkx tibiil; FPT = femorai-posterkx tibiat; P = patent; BK = below-knee; AK = above-knee.
Sauvage et al [5], in comparing different graft fabrics, described PTFE as fulfilling four of five criteria for an ideal synthetic graft. These qualities provide a versatility and durability not found in other synthetic grafts. The characteristic graft structure allowing full heparinization without the need to preclot the graft obviously bestows a significant advantage. Because the spectrum of disease is so variable, it is difficult to compare the results of different forms of grafting material in limb salvage procedures. There are a number of reasons for this. The natural history of atherosclerosis associated with an ischemic limb is such that patient survival is frequently measured in months rather than years. Our assessment of the extent of disease and our decision to bypass a particular limb in terms of the quality of distal runoff as demonstrated by monoplane arteriography is primarily subjective even in the presence of Dopplerassessed calf pressures. The experience of the surgeon, his technical ability, and his philosophy regarding limb salvage are all qualities that fail to lend themselves readily to objective analysis. Nevertheless, they frequently influence the outcome of the procedure. Therefore, to compare patients in terms of the number of patent distal vessels is a fruitless exercise where quality of the runoff is so much more important. Clearly, one of the main advantages of the PTFE graft over other synthetic grafts is that it can be used effectively across the knee ioint and into small arteries, provided.the runoff is adequate. Ease of handling and resistance to infection [3] are further advantages.
In some centers, limb salvage has become an emotional issue with those who believe that amputation and rehabilitation represent the most expeditious means of mobilizing patients versus others who believe that almost anything is justified in pre-
Volume 136, August 1979
venting limb loss. It is undisputedly true that many patients in whom limb salvage or rehabilitation fail will be converted from an independent to an institutionalized state. While this facet must be kept in perspective, the answer probably lies somewhere between these two philosophies. The approach at Vancouver General Hospital toward limb salvage is moderately aggressive. Long limb PTFE bypasses sometimes coupled with extraanatomic grafts to improve arterial inflow have been used in limb salvage attempts usually with gratifying results. Concomitant use of heparin and low molecular weight dextran in the first 48 hours postoperatively may aid patency. Although our overall graft patency rate was 70 per cent (mean follow-up, 13.2 months), as indicated by palpable pulses or increased ankle pressures, our limb salvage rate was 80 per cent (16 of 20 patients) over this period. These figures approximate those of Campbell et al [2] who achieved 87 per cent limb salvage in fifteen patients, one of whom had a long bypass. However, in the present series, there were twelve limbs in which long bypasses were performed.
TABLE IV
Patient HO EB GS GF
GF vs
PTFE Bypass Into Single Domlnant Vessels Indications
Anastomotic Sites
Patency at Discharge
G RP RP RP RP G
FPer FAT FPer FPT FPT FAT
P P P P P P
MO
Patent
Salvage
15 Yes 13 Yes 15 Yes 13 Yes 11 Yes 14 Yes mean: 13.50
Note: G = gangrene; RP = rest pain; FPer = femoroperoneal: FAT = femoral-anterior tibial; FPT = femoral-posterior tibial; P =
patent.
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Fry and Robertson
Figure 7. HO, a sixty-five year old male, with single dominant peroneal vessel supplying the leg demonstrated preopefatlvely.
There were six patients (Table IV) in whom long bypasses were placed into single dominant vessels below the knee. (Figures 1 and 2.) On each occasion, monoplane arteriography demonstrated the single vessel to be relatively free of atherosclerosis. Currently, all six patients have patent grafts (mean, 13.5 months), and limb salvage has been achieved. In these patients, a 6.5 to 4.5 mm tapered graft was used. The small number of patients involved prevents any conclusions from being drawn regarding graft position and patency. (Table V.) The fact that the three peroneal bypass grafts and five of seven anterior and posterior tibia1 grafts remained patent reflects the choice of bypass into a single dominant vessel but illustrates that these grafts do well in below-knee positions. This aspect is further demonstrated when assessment of patency in terms of the number of runoff vessels is made. (Table VI.) Here it is evident that the greatest patency rates were achieved where bypass was performed into a single large dominant below-knee vessel. Where double and triple runoff was found, the failure rate approached 50 per cent, because although patency was apparent on monoplane arteriograms, the arteries were often discovered at surgery to be diseased. Analysis of the initial results demonstrates that while the long-term patency of the PTFE graft is as yet unknown, it is suitable for long bypass procedures
196
F/gore 2. Same patlent as In Figure 1 postoperatively, wfth PTFE bypass Into peroneal artery via a lateral approach with resect/on of the flbula.
in the lower limb. The early patency rate at six months where there is adequate distal runoff is 75 per cent. Late failures reduce the patency rate at one year to 70 per cent and appear to be related to the progression of distal disease rather than to mechanical difficulties with the graft itself. Therefore, the PTFE graft seems eminently suitable for bypass or interposition procedures in the absence of a suitable vein,
The American Journal of Surgery
F’TFE Graft
TABLE V
Results of Salvage Procedures in Relation to Graft Position
Position ___--_------.
No. of Grafts
Thrombosis
Amputation
FP (AK) FP (BK) F”T F4T -- F?er
4 6 4 3 3
2 3 1 1 0
1 2 1 1 0
Mean Patency (mo) 17.0 8.16 15.0 13.5 13.5
Note: FP = femoropopliteal; AK = above-knee; BK = belowknee; FPT = femoral-posterior tibial; FAT = femoral-anterior tibial; FPer = femoroperoneal.
Summary
The early results of the bypass procedures for limb salvage using the new polytetrafluoroethylene (PTFE) graft are analyzed. Of twenty patients presenting with either severe rest pain or gangrene, patency has been maintained in fourteen for a mean period of thirteen months to date. Particularly satisfying results have been achieved when bypassing into single dominant arteries below the knee where limb salvage and graft patency was obtained in all cases.
Volume 138, August 1978
TABLE VI No. of - Patients 1 6 9 4
PTFE Graft Patency versus Number of Patent Vessels Runoff Vessels ----_ Single, diseased Single, dominant Double Triple
MO Patency at .___________ Discharge Patent
--._
n 6 6 2 _-_.
0 13.5 12.2 6.25
References 1. Dardik H, Dardik I, Veith FJ: Exposure of the tibial-peroneal arteries by a single lateral approach. Surgery 75: 377. 1974. 2. Campbell CD, Brooks DH, Webster MW, Bahnson HT: Use of expanded microporous polytetrafluoroethylene for limb salvage: a preliminary report. Surgery 79: 485, 1976. 3. Kaplan MS, Mirahmadi MD, Weiner R. Gorman JT: Resistance of PTFE grafts to early or late infections. Presented at the Seventh Annual Meeting of the Western Dialysis and Transplant Society, Seattle, Washington, October 1976. 4. Matsumoto H, Hasegawa T, Fuse K, Yamamoto M, Saigusa M: A new vascular prosthesis for a small caliber artery. Surgery 74: 519, 1973. 5. Sauvage LR, Berger KE, Mansfield PB, Wood SJ, Smith JC, Overton JB: Future directions in the development of arterial prostheses for small and medium caliber arteries. Surg C/in North Am54: 213, 1974.
197