Transluminal angioplasty of venous stenoses in polytetrafluoroethylene vascular access grafts

Since 1984, percutaneous transluminal angioplasty (PTA) utilizing high pressure balloon catheters has been used as an initial approach to restore patency of PTFE (polytetrafluoroethylene, GORE-TEX) hemodialysis vascular access grafts. Seventeen stenotic lesions detected by fistulogram underwent elective PTA. Twelve of these lesions were detected after thrombectomy and five were detected because of increased venous pressures during dialysis. Fourteen attempts at PTA were completely successful in restoring functional patency to the vascular graft. Three attempts were unsuccessful; two of these three grafts were subsequently repaired surgically. Venous stenoses that extended far greater than 6 cm were not considered for PTA. We conclude that PTA is a technique of promise in the non-surgical salvage of failing PTFE grafts. PTA can prolong the useful life of PTFE vascular access grafts and can be performed on an outpatient basis, eliminating the hospitalization that is usually required for surgical revision.     

Changing arteriosclerotic disease patterns and management strategies in lower-limb-threatening ischemia.

From January 1, 1974 to December 31, 1989, we treated 2829 patients with critical lower-extremity ischemia. In the last 5 years, 13% of patients had therapeutically significant stenoses or occlusions above and below the groin, while 35% had them at two or three levels below the inguinal ligament. Unobstructed arterial flow to the distal half of the thigh was present in 26% of patients, and 16% had unobstructed flow to the upper third of the leg with occlusions of all three leg arteries distal to this point and reconstitution of some patent named artery in the lower leg or foot. In the last 2 years, 99% of all patients with a threatened limb and without severe organic mental syndrome or midfoot gangrene were amenable to revascularization by percutaneous transluminal angioplasty (PTA), arterial bypass, or a combination of the two, although some distal arteries used for bypass insertion were heavily diseased or isolated segments without an intact plantar arch. Limb salvage was achieved and maintained in more than 90% of recent patient cohorts, with a mean procedural mortality rate of 3.3%. Recent strategies that contributed to these results include (1) distal origin short vein grafts from the below-knee popliteal or tibial arteries to an ankle or foot artery (291 cases); (2) combined PTA and bypass (245 cases); (3) more distal PTA of popliteal and tibial artery stenoses (233 cases); (4) use of in situ or ectopic reversed autogenous vein for infrapopliteal bypasses, even when vein diameter was 3 to 4 mm; (5) composite-sequential femoropopliteal-distal (PTFE/vein) bypasses; (6) reintervention when a procedure thrombosed (637 cases) or was threatened by a hemodynamically significant inflow, outflow, or graft lesion (failing graft, 252 cases); (7) frequent follow-up to detect threatening lesions before graft thrombosis occurred and to permit correction of lesions by PTA (58%) or simple reoperation; and (8) unusual approaches to all infrainguinal arteries to facilitate secondary operations, despite scarring and infection. Primary major amputation rates decreased from 41% to 5% and total amputation rates decreased from 49% to 14%. Aggressive policies to save threatened limbs thus are supported.     

Value and limitations of secondary femoropopliteal bypasses with polytetrafluoroethylene

Secondary femoropopliteal bypasses with polytetrafluoroethylene (PTFE) grafts are widely regarded to be of questionable value. This has prompted some to abandon all attempts at secondary revascularization with PTFE and others to recommend that primary femoropopliteal bypasses be performed preferentially with PTFE grafts so that vein may be used for secondary procedures. Because we questioned both of these views, we reviewed all femoropopliteal bypasses done at our institution in the past 12 years and identified 73 secondary PTFE femoropopliteal procedures performed after a failed ipsilateral infrainguinal bypass (69 failed femoropopliteal; 4 failed femorodistal). Seventy (96%) secondary bypasses were performed for limb salvage and 3 (4%) for severe disabling claudication. Insertion of grafts to the popliteal artery was above the knee in 26 (36%) and below the knee in 47 (64%). Primary life-table graft patency at 4 years was only 38%. Forty-eight reinterventions in 34 limbs were required to restore or maintain graft patency in thrombosed or failing grafts. For thrombosed grafts, 20 interventions consisted of 9 simple thrombectomies and 11 thrombectomies with additional revision procedures (5 distal or proximal extensions, 6 patch angioplasties). Twenty-eight lesions threatening graft patency were treated by percutaneous transluminal angioplasty in 3, proximal or distal extensions in 20, and patch angioplasty in 5. As a result of these reinterventions, the overall secondary patency rate was 55% at 4 years, and the limb salvage rate was 74% at 4 years. Although aggressive follow-up and reintervention may be required, the use of secondary PTFE conduits in the femoropopliteal position is a viable option in patients undergoing limb salvage procedures who are at high risk.(ABSTRACT TRUNCATED AT 250 WORDS)     

Durability of vein graft revision: the outcome of secondary procedures

Occlusive lesions that reduced graft blood flow and ankle systolic pressure were identified in 83 femorodistal saphenous vein bypasses by use of duplex scanning or arteriography. Sites of stenosis included vein conduit (n = 41), anastomoses (n = 20), outflow arteries (n = 15), or inflow (n = 9) arteries. One hundred three secondary procedures consisting of vein-patch angioplasty (n = 31), sequential (n = 21) or interposition (n = 17) graft placement, percutaneous transluminal balloon angioplasty (n = 17), or excision of the lesion and primary anastomosis (n = 16) were performed to correct primary (n = 85) or recurrent (n = 18) graft stenoses. Cumulative graft patency after reintervention was 96% at 1 year, and 85% at 5 years. Stenosis or occlusion of revision sites was less after excision (0 of 16) or replacement (1 of 17) of abnormal segments compared to vein-patch angioplasty (8 of 31) or balloon angioplasty (9 of 18). Sequential or jump grafts constructed to improve graft outflow impaired by either myointimal or atherosclerotic occlusive lesions were the least durable secondary procedures. Five of eight graft failures in this series resulted from sequential/jump graft occlusion. All categories of secondary procedures normalized graft and limb hemodynamics, although only one third of patients reported symptoms of limb ischemia before revision. Surveillance of infrainguinal vein bypasses for occlusive lesions is a valid concept to salvage patent but hemodynamically-failing grafts. Secondary procedures that excised the lesion, used autologous tissue reconstruction, and normalized hemodynamics at the revision site and in the vein bypass were associated with a low incidence of restenosis and prolonged graft patency.     

Arm vein reconstruction for limb salvage: long-term outcome.

A series of 42 consecutive patients undergoing infrainguinal vascular reconstruction for limb salvage using vein harvested from the arm were followed prospectively to determine the long-term graft patency and stenosis rates. Vein harvested from the arm ('arm vein') was used for secondary or tertiary reconstruction in 22 patients (52.4%). The outflow was to a single calf vessel in 37 grafts (88.1%). The cumulative primary, primary assisted and secondary graft patency rates were 35.6%, 49.6% and 59.5% at 2 years, respectively, and the limb salvage rate was 69.0% at 2 years. Eight grafts developed stenoses detected by a graft surveillance programme. Six stenoses were dilated successfully with percutaneous transluminal angioplasty (PTA) and one was treated with an interposition vein graft. Bypass using arm vein is time-consuming and technically demanding as multiple anastomoses are often required. Arm vein grafts, however, have no greater incidence of stenosis than long saphenous vein grafts and these stenoses may be dilated with PTA with good results. The long-term outcome suggests that an arm vein graft is an important treatment option in the absence of the long saphenous vein.     

Outcome of endovascular intervention for infrainguinal vein graft stenosis

Assisted graft patency rate following revision of a graft stenosis is far better than that following thrombectomy of an occluded graft. Graft revision by endovascular means has been proposed as a suitable alternative to more invasive surgery. This study reports our experience with endovascular treatment of vein graft stenosis. Between December 1992 and September 2000, percutaneous transluminal balloon angioplasty (PTA) was performed on 90 vein graft stenoses in 87 infrainguinal vein bypass grafts identified by routine graft duplex scan (peak systolic velocity, PSV > 300 cm/sec). All 90 stenoses treated by PTA were retrospectively analysed for stenosis-free patency rate (life-table analysis). Re-stenosis was defined by PSV exceeding 300 cm/sec at the same site of the vein graft where a stenosis was dilated.Ninety vein graft stenoses (72 primary stenoses and 18 recurrent stenoses) in 33 femoropopliteal (above knee), 30 femoropopliteal (below knee) and 24 femorotibial vein bypass grafts were treated by PTA. The timing of PTA ranged from one to 252 months (mean, 23.9 months) from the initial surgery. Cumulative stenosis-free patency rate after PTA was 55.8% at 6 months, 54.0% at one year and 45.0% at three years. Stenosis-free patency rate at six months was significantly lower for revision of recurrent stenosis (25.9%) than for primary stenosis (61.6%) (P = 0.01). The revision of duplex scan detected vein graft stenosis with endovascular intervention was associated with an acceptable stenosis-free patency rate. However, recurrent stenosis treated by PTA had a significantly inferior outcome. Direct surgical revision would be more appropriate for recurrent lesions.     

Late failure of reversed vein bypass grafts.

Late failure of reversed vein bypass grafts is preceded by the appearance of stenotic lesions, which progress to total occlusion. These lesions appear either as intrinsic graft lesions or as new arteriosclerotic lesions in contiguous arteries. The present study summarizes the University of Pennsylvania experience with these lesions in 521 vein grafts inserted from 1979 to 1985. The grafts were grouped according to the site of the distal anastomosis; 231 above-knee popliteal (FP AK), 171 below-knee popliteal (FP BK), and 119 tibial (FT). The overall incidence of stenotic lesions was essentially identical with the three grafts (21%), but the relative incidence of intrinsic graft to arterial lesions was higher with the more distal grafts. The most common graft lesions developed adjacent to the proximal anastomosis, which is the narrowest part of a reversed vein graft. The popliteal artery was the most common site of outflow stenosis. There was negligible incidence of tibial lesions. The most common inflow arterial lesion was located in the common femoral and iliac arteries. The superficial femoral artery (SFA) was a rare site of inflow stenosis, even though it was at risk because 96 grafts originated from the SFA or popliteal artery. Sixty-seven per cent of the graft and 52% of the arterial lesions were treated successfully by percutaneous transluminal angioplasty; the rest had minor surgical revisions. This resulted in a 19%, 10%, and 9% improvement in 5-year patency for the FT, FP BK, and FP AK bypasses. These results justify an aggressive policy of graft surveillance to identify and treat stenotic graft lesions before graft occlusion.     

Optimizing infrainguinal arm vein bypass patency with duplex ultrasound surveillance and endovascular therapy

OBJECTIVE: Infrainguinal bypass grafting with arm vein is associated with lower patency rates compared with saphenous vein conduits. In this study the effect of a duplex ultrasound surveillance program to enable identification and treat graft lesions with open or endovascular repair on patency was analyzed. METHODS: Over 9 years 89 infrainguinal arm vein (26% spliced vein) bypasses were performed to treat critical lower limb ischemia in 89 patients without adequate saphenous vein conduits. Seventy-six (85%) of the bypasses were repeat procedures. Grafts were assessed at operation with duplex ultrasound scanning, then enrolled in a surveillance program. Graft stenoses with peak systolic velocity greater than 300 cm/s and velocity ratio greater than 3.5, detected at duplex ultrasound scanning, were repaired with percutaneous transluminal balloon angioplasty (PTA) if specific criteria were met, including greater than 3 months since primary procedure, lesion length less than 2 cm, and graft diameter greater than 3.5 mm, or with open surgical repair for early appearing or extensive graft lesions. RESULTS: During a mean 26-month follow-up, duplex surveillance resulted in a 48% (43 bypasses) intervention rate. Primary patency rate was 43% at 3 years. Twenty-six (43%) of 61 lesions identified and repaired met criteria for PTA; the remaining 35 graft lesions (stenosis, n = 30; vein graft aneurysm, n = 5) were surgically corrected with vein patch angioplasty (n = 15), interposition grafting (n = 13), jump graft bypass (n = 6), or open repair (n = 1). At 3 years the assisted primary patency rate was 91% (7 graft failures). Multiple interventions were performed in 18 (42%) revised grafts because of metachronous (n = 6) or repair site stenosis (n = 12). In 18 graft interventions (PTA, n = 9; surgery, n = 9) recurrent stenosis developed, and endovascular therapy was used in one third (n = 6). At 3 years the stenosis-free patency rate for PTA (48%) and surgically repaired (53%) graft lesions was similar. CONCLUSIONS: Arm veins used in lower limb bypass procedures are prone to development of stenosis and aneurysm, lesions easily detected with a life-long duplex ultrasound surveillance program. Excellent long-term patency (91%) was achieved despite graft intervention being performed in nearly half of all bypasses and one third of revised grafts. Endovascular treatment was possible in half of all graft stenosis, with outcomes similar to those with surgical repair.     

Outcome of surgical and endoluminal intervention for infrainguinal bypass anastomotic strictures

The objective of this study was to compare the outcomes of percutaneous transluminal angioplasty (PTA) versus open surgical repair of anastomotic strictures affecting infrainguinal bypasses. Anastomotic strictures affecting 39 bypasses in 36 patients were identified among 593 consecutive infrainguinal arterial reconstructions performed between 1994 and 2004. The mean age of affected patients was 65 +/- 2 years (range: 61 to 101 years). The original bypasses, with vein grafts outnumbering prosthetic grafts 2 to 1, were performed for acute (5%) and chronic (54%) limb-threatening ischemia, disabling claudication (28%), or popliteal aneurysms (13%). Anastomotic strictures were first recognized an average of 16 +/- 3 months (range 2 to 92 months) postoperatively. Strictures affected the distal anastomosis in 62% of cases and the proximal anastomosis in 38%. Primary patency, assisted primary patency, secondary patency, and limb salvage were assessed following PTA or open surgical repair of the strictures. Anastomotic strictures were detected following acute (41%) and chronic (18%) limb-threatening ischemia, claudication (13%), or during routine graft surveillance (28%) in asymptomatic patients. Graft thrombosis, occurring in 51% of patients at the time of presentation, was not affected by the site of anastomotic stricture, although prosthetic grafts were affected more than vein grafts (92% vs 31%). Interventions included PTA (67%) and conventional open procedures (33%). The latter included vein patch angioplasty, short interposition grafts, and redo bypasses. The stricture site and bypass material used in the original revascularization did not affect reintervention patency rates. Sixteen (62%) of the endovascular procedures were performed on a graft presenting with thrombosis, while only 4 (31%) were initially treated with operative therapy. Treatment of thrombosed grafts resulted in an 18-month patency of 32% compared to an 80% patency in treating grafts that were not occluded at the time of presentation (p < 0.05). No anastomotic stricture repaired operatively required reintervention, whereas 42% of those treated by PTA required a mean of 1.3 additional reinterventions (p < 0.03). Anastomotic strictures affecting infrainguinal bypass grafts contribute to low patency rates. Outcomes can be significantly improved if these strictures are identified before graft thrombosis. Open surgical repair, compared to PTA, provides improved graft function as evident by fewer subsequent interventions required to maintain graft patency.     

Lysis/balloon angioplasty versus thrombectomy/ open patch angioplasty of failed femoropopliteal polytetrafluoroethylene bypass grafts

PURPOSE: Several studies have reported on the outcome of lysis/percutaneous transluminal balloon angioplasty (PTA) of failed or failing femoropopliteal bypass grafts (FPGs) with mixed results. None of these studies have compared the results of lysis/PTA versus thrombectomy/open patch repair for failed above-knee polytetrafluoroethylene (PTFE) FPGs. METHODS: Patients with failed (thrombosed) above-knee FPGs (PTFE, Goretex) during a 10-year period were given the option to choose between thrombectomy/open patch repair for localized anastomotic short stenosis (less-than-or-equal2 cm; group A, 31 patients) and lysis/PTA or thrombectomy/balloon angioplasty when lysis failed or was contraindicated (group B, 26 patients). The cumulative patency rates were compared by using a Kaplan-Meier life table analysis. All patients underwent routine color duplex ultrasound scanning/ankle brachial index measurements at 30 days, 6 months, and every 6 months thereafter. RESULTS: Demographic and clinical characteristics and indications for intervention were comparable in both groups. The mean follow-up period was 54.1 and 46.2 months in group A and group B, respectively. There were four perioperative complications in group A (13%) and seven perioperative complications in group B (27%). Initial technical success and 30-day secondary graft patency rates were 100% in both groups. Overall, 17 of 31 patients (55%) had open grafts, with no further revisions in group A and six of 26 patients (23%) in group B requiring further revisions (P =.012). Nine of 31 grafts (29%) failed in group A versus 15 of 26 grafts (58%) in group B (P =.027). The rate of limb loss was comparable in both groups (6% vs 12%). The overall cumulative secondary patency rates at 6 months and 1, 2, 3, 4, and 5 years were 100%, 93%, 85%, 72%, 67%, and 62% for group A and 100%, 96%, 88%, 76%, 63%, and 45% for group B (P =.035). Thirty-five further interventions were needed to maintain graft patency in group B (mean, 1.35; range, 0-3) versus five further interventions in group A (mean, 0.16; range, 0-1; P <.05). CONCLUSION: Thrombectomy/open surgical repair is superior to lysis/PTA (or thrombectomy/balloon angioplasty) for the treatment of failed above-knee PTFE FPGs with anastomotic stenoses. Therefore, balloon angioplasty should be reserved for patients who are at high risk for surgery.     

Infrainguinal vein graft stenosis: cutting balloon angioplasty as the first-line treatment of choice

OBJECTIVE: The optimal treatment for hemodynamically significant infrainguinal vein bypass graft stenosis is not known. This study compares three options as first choice for the revision of failing infrainguinal vein grafts: cutting balloon angioplasty (CBA), standard percutaneous transluminal balloon angioplasty (PTA), and open surgical revision (OS). METHODS: Infrainguinal vein bypass graft lesions treated in a single institution during a 12-year period were evaluated. Of these, 161 lesions in 124 infrainguinal bypasses (101 patients) were treated with OS (n = 42), PTA (n = 57), or CBA (n = 62). The initial indication for the bypass in these patients was limb salvage in 73% and claudication in 27%. The primary outcome of interest was the development of vein graft occlusion or significant stenosis (>or=70%) as detected by surveillance duplex ultrasound scanning or arteriography some time after repair. RESULTS: The stenosis-free patency rates at 48 months for OS, CBA, and PTA were 74%, 62%, and 34%, respectively. PTA was associated with an increased risk of treatment failure compared with both OS (hazard ratio [HR], 3.9; P < .0001) and CBA (HR, 3.1; P < .0001). There was no significant difference between OS and CBA (HR, 1.3 for CBA vs OS, P = .6). Pseudoaneurysms developed in two CBA patients. One ruptured and required interposition graft, and one was monitored. CONCLUSION: Cutting balloon angioplasty is a reasonable, initial treatment for infrainguinal vein graft stenosis in most patients. It is a safe, minimally invasive, outpatient procedure with patency rates that are comparable to OS and superior to PTA.     

Improved patency in reversed femoral-infrapopliteal autogenous vein grafts by early detection and treatment of the failing graft

One hundred two femoral-infrapopliteal bypasses, in which reversed autogenous saphenous vein grafts were used, were performed from January 1978 to July 1984, in 94 patients with severe claudication (14%) or threatened limb loss (86%). Follow-up examinations at 3-month intervals during the first 18 months and at 6-month intervals thereafter were performed to document the return of ischemic symptoms or loss of peripheral pulses. Ankle pressure index and pulse volume recordings were also measured. A decrease in ankle pressure index equal to or greater than 0.2 or a pulse volume recording decrease of 5 mm or more with or without confirmatory symptoms were indications for repeat arteriography. Twenty-two primary graft or anastomotic stenoses were discovered in 19 grafts during follow-up. Seventy-eight percent of these lesions were treated primarily by percutaneous transluminal angioplasty and the remainder were treated by short proximal interposition grafts or patch graft angioplasty. Twenty-five grafts occluded during follow-up and all of these were considered to have failed for purpose of life-table analysis. Stenotic lesions, which were corrected before occlusion, were listed as continuously patent under secondary patency and as failed under primary patency life-table analysis. The secondary graft patency rate was 70% at 5 years, which was significantly higher (p less than 0.01) than the primary patency rate (47%), which was obtained without intervention. This 23% differential represents graft salvage achieved by careful surveillance and is reflected not only by improved patency but also by high limb salvage rates (86%) observed at 5 years.     

Diagnosis and management of failing lower extremity arterial reconstructions prior to graft occlusion

In 191 instances, infrainguinal graft occlusion was presumed because of a rethreatened foot, diminished pulses and/or decreased ankle pressure. Routine urgent arteriography revealed 38 instances where the graft was patent (22 vein, 16 PTFE). Ten of these grafts were to the femoral artery, 18 to the popliteal artery and 10 were to infrapopliteal arteries. The deterioration despite a patent graft was due to development of inflow stenosis (15), vein graft lesions (13) or distal disease progression (10). All were treated successfully by percutaneous transluminal angioplasty (30) or simple local operative revisions (8). Cumulative life table patency rates 2 years after reintervention were 89% for failing reconstructions to the femoral artery, 94% for those to the popliteal artery and 89% for infrapopliteal procedures. Comparable rates for limb salvage were 90%, 100% and 100%, respectively. These findings underscore the importance of urgent angiography in suspected lower extremity graft failure. Defects may be detected before real graft occlusion occurs and appropriate interventional treatment can provide important additional periods of limb salvage.     

Operative transluminal balloon angioplasty. Adjunct to coronary bypass for extended myocardial revascularization of more than 3000 lesions in 1000 patients

Operative transluminal coronary artery balloon angioplasty has been used for over 3000 lesions in 1000 patients since 1980. Initially it was only used for distal stenoses not accessible to coronary bypass grafting in 200 patients. Recatheterization of patients who had intraoperative transluminal balloon angioplasty of the proximal left anterior descending, right, and circumflex coronary arteries 3 years previously revealed excellent patency of both the bypass grafts and the dilated native coronary arteries. This observation supports the thesis that with properly constructed bypass anastomoses competitive flow does not significantly mandate graft thrombosis. Subsequently, intraoperative balloon angioplasty has been performed for both proximal and distal stenoses in 800 patients to improve native coronary artery perfusion and maximize revascularization. Follow-up from 1 to 7 years revealed perioperative myocardial infarction in 21 patients (2.1%) and death in 19 patients (1.9%). Recatheterization from 1 to 7 years after the operation in 51 patients (41 with symptoms) revealed that patency was almost as prevalent in arteries subjected to angioplasty (82%; 137/167) as in bypass grafts (84%; 102/122). Intraoperative balloon angioplasty appears to improve coronary artery perfusion without detrimental competitive flow when used with bypass grafts.     

Percutaneous transluminal angioplasty as an adjunct to the surgical management of peripheral vascular disease.

Percutaneous transluminal angioplasty (PTA) was performed as an adjunct to an operation in 43 patients with peripheral arterial insufficiency. This represents 26% of patients undergoing PTA over the past 44 months. In 23 patients PTA was done in conjunction with planned vascular reconstruction. It was successful in all 23 patients, and patency of the vascular graft was maintained in 22 patients during a mean follow-up period of nine months. Fourteen patients had PTA after operation. It was successful in 13 of them, and vascular patency was maintained in all 13 during a mean follow-up period of four months. Six patients had PTA prior to a distal amputation or a skin graft. All healed promptly. The overall initial success rate of PTA was 98%, the complication rate was 2%, with a late failure rate of 2%. It is concluded that PTA is a valuable adjunct to vascular surgery to improve inflow or outflow for bypass grafts, to reduce the extent of the operation in poor risk patients, to facilitate the healing of distal amputations, and to manage late graft stenosis.     

Six year experience with expanded polytetrafluoroethylene arterial grafts for limb salvage

We have used 822 polytetrafluoroethylene (PTFE) grafts in arterial reconstructions for limb salvage over the last 6 years at Montefiore Medical Center-Albert Einstein College of Medicine, Four hundred and twenty-seven femoropopliteal reconstructions with PTFE had a 6 year cumulative life table patency rate of 55% with follow-up of 76 grafts for more than 3 years and 28 grafts for more than 4 years. Seventy-nine bypasses to the isolated popliteal segment had a 6 year cumulative patency rate of 72%. There were 207 bypasses performed to the tibial, peroneal or dorsalis pedis arteries. Life table patency rates were 55% at 1 year, 40% at 2 years and 37% at 4 years. Ninety-two PTFE femorofemoral and 62 axillofemoral bypasses had 5 1/2 year cumulative life table patency rates of 83% and 75%, respectively. Axillopopliteal PTFE bypasses can salvage otherwise doomed limbs. Thirty-four such grafts had 74% 1 year and 45% 5 year patency rates. The overall infection rate in all 822 PTFE grafts was only 0.5%. Thus, PTFE is a promising vascular prosthetic material which facilitates otherwise difficult or impossible limb salvage procedures.     

Surgical and endovascular intervention for infrainguinal vein graft stenosis

Purpose: The purpose of this study was to evaluate the stenosis-free patency of open repair (vein-patch angioplasty, interposition, jump grafting) and percutaneous transluminal balloon angioplasty (PTA) of 144 vein graft stenoses that were detected during duplex scan surveillance after infrainguinal vein bypass grafting. Methods: Patients who underwent revision of an infrainguinal vein bypass graft were analyzed for type of vein conduit, vascular laboratory findings leading to revision, repair techniques, assisted graft patency rate, procedure mortality rate, and restenosis of the repair site. Results: The time of postoperative revision ranged from 1 day to 133 months (mean, 13 months). One hundred eighteen primary and 26 recurrent stenoses (peak systolic velocity, >300 cm/s) in 52 tibial and 35 popliteal vein bypass grafts were identified by means of duplex scanning. The repairs consisted of 77 open procedures (vein-patch angioplasty, 28; vein interposition, 33; jump graft, 9; primary repair, 3) and 67 PTAs. No patient died as a result of intervention. Cumulative assisted graft patency rate (life-table analysis) was 91% at 1 year and 80% at 3 years. At 2 years, cumulative assisted graft patency rate was comparable for saphenous vein grafts (reversed, 94%; in situ, 88%; nonreversed, 63%) and alternative vein grafts (89%). Stenosis-free patency rate at 2 years was identical (P = .55) for surgical intervention (63%) and endovascular intervention (63%) but varied with type of surgical revision (P = .04) and time of intervention (<4 months, 45%; >4 months, 71%; P = .006). The use of duplex scan–monitored PTA to treat focal stenoses (<2 cm) and late-appearing stenoses (>3 months) was associated with a stenosis-free patency rate that was 89% at 1 year. After intervention, the alternative vein bypass grafts necessitated twice the reinterventions per month of graft survival (P = .01). Bypass graft to the popliteal versus infrageniculate arteries, site of graft stenosis (vein conduit, anastomotic region), and repair of a primary versus a recurrent stenosis did not influence the outcome after intervention. Conclusion: The revision of duplex scan–detected vein graft stenosis with surgical or endovascular techniques was associated with an excellent patency rate, including when intervention on alternative vein conduits or treatment of restenosis was necessary. When PTA was selected on the basis of clinical and duplex scan selection criteria, the endovascular treatment of focal vein graft stenosis was effective, durable, and comparable with the surgical revision of more extensive lesions. (J Vasc Surg 1999;29:60-71.)     

Prospective randomized multicenter comparison of in situ and reversed vein infrapopliteal bypasses

We have performed a prospective, randomized, multicenter study to compare in situ and reversed vein grafts for long limb salvage bypasses from the proximal thigh to an infrapopliteal artery. Three hundred eighty-four patients required an infrapopliteal bypass for critical lower extremity ischemia. Of these, 259 were excluded because a short vein bypass was performed or because the vein was considered inadequate. The remaining 125 patients had a randomized vein bypass, 63 reversed, 62 in situ. The two groups were similar with regard to risk factors, indications, graft dimensions, and outflow. Secondary patency at 30 months was similar for both techniques: reversed 67% +/- 9% (+/- SE); in situ 69% +/- 8%. For veins less than or equal to 3.0 mm in minimum distended diameter 24-month patency rates were 61% +/- 22% for 12 in situ veins and 37% +/- 29% for 10 reversed veins (p greater than 0.05). Angiographic evaluation of failing grafts revealed lesions similar in type and frequency in both types of grafts. These included focal (in situ, n = 4; reversed, n = 7) and diffuse vein hyperplasia (in situ, n = 2; reversed, n = 1), and inflow and outflow stenoses (in situ, n = 4; reversed, n = 3). The incidence of wound complications and the mortality rate were similar for the two groups. These data show no significant difference in overall patency rates for the two types of vein grafts at 2 1/2 years.(ABSTRACT TRUNCATED AT 250 WORDS)     

The use of covered nitinol stents to salvage dialysis grafts after multiple failures

The increasing number of patients requiring hemodialysis and the limited number of access sites have resulted in an increase in multiple graft revisions to maintain access for hemodialysis. Venous outflow or anastomotic stenoses in vascular grafts tend to recur and contribute to the difficulty in maintaining a functioning graft. Thus, extending the life of a failed graft becomes an important objective of this study, which was to assess the use of covered nitinol stents to salvage expanded polytetrafluoroethylene (ePTFE) grafts with venous anastomotic or outflow stenosis that have failed after multiple revisions. This is a review of 8 failed non-autogenous ePTFE grafts with isolated venous anastomotic or proximal outflow stenoses that had undergone multiple previous revisions, had failed percutaneous transluminal angioplasty (PTA), and required placement of a covered nitinol stent. Graft locations were forearm (2), upper arm (4), and femoral (2). The mean number of interventions per patient before stent placement was 5.87 thrombectomies (range 2-28) and 3.38 balloon angioplasties (range 2-19). Five patients had 0.62 interposition grafting and 3 had patch angioplasty. All 8 patients (100%) underwent successful dialysis after thrombectomy and stenting. The primary and secondary patency rates after stent placement were 50% and 75%, and 25% and 75%, at 3 and 6 months, respectively. Percutaneous thrombectomy, balloon angioplasty, and concomitant covered nitinol stent placement extend the function of hemodialysis access grafts that have previously failed multiple times.     

Treatment of "swing point stenoses" in hemodialysis arteriovenous fistulae

AIM: This is a retrospective study of percutaneous transluminal balloon angioplasty (PTA) efficacy for treatment of surgical vein mobilization site ("swing point") stenoses in hemodialysis arteriovenous fistulae (AVF) that fail to mature or are poorly functioning. METHOD: Between February 1, 1999, and February 28, 2001, 65 non-maturing or poorly functioning AVF were studied in 63 consecutive hemodialysis patients (30 male, 33 female, aged 26-92 years). All AVF underwent contrast angiography to study the inflow artery, AVF, outflow and central veins. PTA of stenotic sites was performed to initiate or restore AVF function. RESULTS: Seventy-eight venous and 2 arterial stenoses were found and treated with PTA in the 65 AVF. All PTA were technically successful. A total of 55 stenoses were identified in the vein at the site of surgical mobilization ("swing point"). Additionally, 19 cephalic and 4 central venous stenoses were found. During the study, 13 AVF underwent repeat PTA at the "swing point". Of the 65 AVF treated, 50 were being successfully used as an access site, 4 AVF were lost during follow-up (34-688 days; mean: 258 days) and 8 patients died within the study period. The duration of functional patency of the treated AVF was 39-660 days (mean: 280 days). CONCLUSION: Non-maturing or poorly functioning AVF frequently have stenoses in the outflow vein at the original site of surgical vein mobilization. These "swing point stenoses" are amenable to PTA, which is a safe and effective treatment for prolonging AVF patency and function.