Subclavian to carotid artery transposition: medial versus lateral approach.

INTRODUCTION: Subclavian to carotid transposition (SCT) is gaining importance as an adjunct for thoracic endovascular aortic repair (TEVAR). Two different anatomical approaches are described. We reviewed our experience with both approaches to evaluate the occurrence of complications and long-term outcome. MATERIALS/METHODS: We report the outcome of 150 SCTs carried between October 1979 and April 200710/79 at 2 university based tertiary care centers. Independent neurologic evaluation was performed. RESULTS: Lateral and medial approaches were used in 83 (55.4%) and 67 (44.6%) cases, respectively. The internal thoracic artery and the thyrocervical trunk were sacrificed more frequently when the lateral approach was used (1.5% vs 39.8%; p=0.0001 and 1.5% vs 49.4%; p=0.0001, respectively). The medial approach was associated with significantly less complications (8, 11.9%, compared to 24, 28.9%, p=0.012). Thirty day mortality was 0.7%. Median follow-up was 36 months (1-227), and no subclavian artery occlusions were identified. CONCLUSIONS: SCT is a durable procedure for the management of occlusive pathologies of the proximal subclavian artery occlusion. The medial approach is associated with significantly fewer complications.

Midterm durability of abdominal aortic aneurysm endograft repair: a word of caution.

PURPOSE: Endograft technology for abdominal aortic aneurysm (AAA) repair is being applied more liberally. There is little information about the midterm performance of these grafts. This study is focused on follow-up interventions after endograft repair for AAA. METHODS: Prospective follow-up analysis of a consecutive patient series (n = 173 patients) at a single center who underwent endovascular AAA repair up to 50 months after operation. Seventeen percent of the patients were regarded unfit for open surgery. Four types of commercially available grafts were used. The Society for Vascular Surgery/International Society for Cardiovascular Surgery guidelines were applied for endograft implantation and data preparation. RESULTS: In two patients, the procedure was converted to open surgery. In one procedure, emergency repair for iliac artery rupture was performed. The 30-day mortality rate was 2.8% (n = 5 patients). An early second procedure to correct type I endoleaks was necessary in 8 cases (4.6%; 3-10 days). The following midterm results were obtained: median follow-up of the 166 remaining patients was 18 months (range, 1-50 months); 50 additional procedures were necessary in 37 patients (22.3%) for the treatment of leaks (n = 45 interventions) or to maintain graft patency (n = 5 grafts; four patients with concomitant graft segment disconnection); and 46% of the reinterventions were performed within the first year of follow-up and 74% of the reinterventions were performed within the second year of follow-up. One patient died after emergency surgery for rupture as the result of a secondary endoleak at 1 year. Although seven interventions (14%) were performed for type II endoleak, no serious complications were related to patent sidebranches. There was no statistically significant difference between the need for maintenance in different graft configurations (tubular, bifurcated, aorto-uniiliac), or number of graft segments (1, 2, 3-4, > or = 5 segments). New generation grafts (after 1996) performed better than early generation grafts (P = 0.04, chi-squared test) with regard to endoleak development. CONCLUSION: Endograft repair for AAA is safe but, with current technology, not as durable as open repair. Our data suggest that the use of endograft repair for AAA is becoming safer as endograft design improves. Nevertheless in 26.6% of the patients, there is need for reintervention within midterm follow-up. Close follow-up is crucial because late leaks may develop after more than 2 years after the initial procedure. Endoluminal repair should therefore be applied with caution, strict indication, and only if a tight follow-up is warranted. These findings may also affect health care reimbursement policies.

Oral anticoagulation in peripheral vascular surgery: how intense, for how long, or at all?

To evaluate the influence of postoperative pharmacotherapy (antiplatelet therapy with acetylsalicylic acid (ASA) or oral anticoagulation) following various peripheral vascular surgical interventions (femoro-popliteal reconstruction, femoro-popliteotibial venous bypass;) two clinical series of patients were analysed (A1-2) and we made the hypothesis that adjuvant therapy may be beneficial. Thereafter two clinical trials were carried out (B1-2), to assess the value of postoperative antiaggregant and anticoagulant treatment. It was not possible to demonstrate any influence of ASA on improving patency at the iliaco-popliteal level or on patient survival. It was concluded that the ASA dosage of 1500 mg daily was too high, and produced severe side-effects, probably leading to insufficient patient compliance to therapy. In the B2 trial 130 patients received a femoro-popliteal above- or below-knee vein bypass, and were assigned to the therapy group (n = 66) and treated with anticoagulants or to the control group (n = 64) which received no therapy. During the follow-up, for a maximum of 10 years, the probability of bypass function, limb salvage and patient survival were significantly in favour of the treatment. The described single centre clinical trial B-2 produced in accordance with other trials a level II evidence in favour of postoperative pharmacotherapy. Level 1 trials assessing the direct comparison of antiaggregant versus anticoagulant therapy are underway, but results are unavailable yet, similarly the results of the Antithrombotic Trialist's Collaboration (ATT) are currently unknown.

Endovascular management of "endoleaks" after transluminal infrarenal abdominal aneurysm repair.

PURPOSE: To investigate the reasons for endoleaks after transluminal infrarenal abdominal aneurysm management and the potential for transluminal interventions in subsequent management. METHODS: Prospective analysis of 50 consecutive patients undergoing endovascular aneurysm repair at a single institution with Stentor and Vanguard grafts from March 1995 to March 1997. SETTING: Academic teaching hospital. RESULTS: Two procedures were converted for other reasons than leak. In the remaining 48 successful procedures endoleaks were detected in 11 (22.9%): proximal aortic leak (2.1%), distal aortic leak (8.3%), iliac leak (12.5%). Leaks were treated at the initial procedure in five patients, resulting in 87.5% excluded aneurysms. Twelve and a half per cent were discharged with a primary leak. Redo was performed on all iliac leaks within 7 weeks. All aortic leaks showed spontaneous thrombosis within 3 months, but reappeared with local aneurysm expansion. Aortic redo-procedures were performed by proximal tubular extension or converting a tube graft into a bifurcation graft. All rescue procedures were successful. Secondary leaks have been observed twice in this series, both treated by endovascular means. CONCLUSIONS: Endovascular treatment of primary and secondary endoleaks is possible, and may be a safe alternative to a difficult open procedure.

Strategies to increase the use of autogenous arteriovenous fistula in end-stage renal disease.

The purpose of this retrospective study was to review our experience with a consecutive group of end-stage renal disease (ESRD) patients using simple strategies to increase the use of autogenous vascular access, and determine whether the current trend of using synthetic bridge-graft fistula (BGF) rather than autogenous arteriovenous fistula (AVF), could be reversed, despite an aging population and broadening criteria for hemodialysis. All patients for vascular access surgery had careful preoperative clinical examination of the arm veins with outflow occlusion to determine the venous anatomy and continuity. Where no veins were apparent or their continuity in doubt, selective preoperative venography was performed. Where veins were unsatisfactory for forearm AVF, new or modified surgical procedures to use both the basilic and cephalic veins in the upper arm were performed. Intraoperative angioscopy was used to monitor vein quality and surgical technique. Ninety-eight primary vascular access procedures were performed in 76 patients, 75 (76.5%) AVF (forearm, n = 41; upper arm, n = 34) and 23 (23.5%) BGF. Forty-one of 76 (54%) had already had at least one previous access procedure prior to this study. More than one access procedure was needed in 16 patients. Preoperative venography was performed in 22 (22.4%) and intraoperative angioscopy in 45 (45.9%) of the 98 procedures. The number of revisions required to maintain patency was significantly higher for BGF (37 revisions in 14/23) than AVF (16 revisions in 13/75) (p < 0.0001, Poisson test) with an annualized secondary revision rate of 1.168 for BGF and 0.173 for AVF (p < 0.0001, Poisson test). AVF had both longer primary (p = 0.0001, log rank test) and secondary patency (p = 0.038, log rank test) than BGF. AVF as the primary vascular access can be significantly increased and the current trend of using BGF reversed with the use of simple clinical strategies to evaluate the suitability of the arm veins for vascular access.

Results of a policy with arm veins used as the first alternative to an unavailable ipsilateral greater saphenous vein for infrainguinal bypass.

PURPOSE: Aggressive policies for distal bypass and coronary revascularization increase the need to identify alternatives to autologous saphenous vein grafts. We examined the performance of arm vein as the primary alternative to contralateral saphenous vein when the ipsilateral saphenous vein was not available. METHODS: A total of 250 arm vein grafts were studied retrospectively in 224 patients (143 men, 81 women, 82.6% with diabetes, mean age 68.3 years) from February 1989 to April 1994. Intraoperative angioscopy was carried out to observe valve lysis, remove abnormalities, and select optimal vein segments. RESULTS: A total of 85 primary, 103 repeat, and 62 graft revision procedures were done for limb salvage in 99.2% of the patients. A total of 41 femoropopliteal, 114 femorotibial-pedal, 33 popliteodistal, and 62 jump or interposition grafts were constructed. A total of 199 grafts were single vein, and 51 were composite vein. The source was cephalic vein alone in 50.4%, cephalic and basilic vein in 35.6%, and basilic vein only in 14%. The contralateral saphenous vein as an alternative conduit was available in 97 (38.8%) instances. Interventions guided by angioscopy to "upgrade" the graft were necessary in 51.6%. Overall early patency (< or = 30 days) was 94.8% (n = 13 occlusions). The cumulative primary patency rate at 1 year was 70.6%, the secondary patency rate was 76.9%, and the limb salvage rate was 88.2%. The 3-year patency rate (limb salvage) was 51.9% (92.4%) for primary grafts, 56.7% (67.1%) in revision grafts, and 42.4% (79.9%) in repeat grafts. In 22.7% (22 of 97) the available contralateral saphenous vein was used for distal revascularization within the follow-up period. CONCLUSIONS: Arm veins are an easily accessible autologous conduit of sufficient length to reach the midtibial level. Excellent patency rates allow durable limb salvage in otherwise difficult circumstances. Vein configuration and splicing do not affect patency rates, but vein quality and repeat operations do. Angioscopy is a valuable adjunct to upgrade graft quality. The contralateral saphenous should be saved for subsequent contralateral revascularization or coronary artery bypass grafting.

The upper arm basilic-cephalic loop for distal bypass grafting: technical considerations and follow-up.

PURPOSE: The performance of a graft created from the upper arm basilic and cephalic veins in continuity was investigated. METHODS: Retrospective analysis of 50 patients, who underwent 54 distal reconstructions with an upper arm vein loop graft between February 1989 and October 1993 (male-to-female ratio of 30/20; mean age of 69.2 years, range 39 to 87; 74% had diabetes) was undertaken. Vein grafts were harvested through a near continuous incision, leaving a skin bridge in the cubita. Intraoperative angioscopy was used to exclude endoluminal disease and to directly observe valvulotomy of the nonreversed part of the graft. RESULTS: Operations were performed for limb salvage in 98.2% of 17 primary and 37 reoperative procedures. Eleven femoropopliteal, 33 femorotibial-pedal, seven popliteal-distal, and two outflow jump grafts were performed. The ipsilateral saphenous vein was unavailable because of previous infrainguinal bypass in 35, coronary artery bypass grafting in 14, and unsuitable quality in 5 cases. Thirty-eight grafts were used in continuity, and 16 grafts required repair or splicing with additional vein segments. Primary 30-day patency rate was 92.6% (n = 4 occlusions). No operative deaths occurred. The cumulative patency rate at 1 year was 74.4%, the limb salvage rate 90.7%. CONCLUSIONS: The upper arm vein loop is a durable graft with excellent short-term and midterm patency rates. Sufficient vein length can be obtained to reach the below-knee and midtibial levels. Angioscopic quality assessment is a valuable adjunct to exclude endoluminal disease most commonly occurring in the median cubital vein. Straightening the curve of the median cubital vein and valvulotomy do not influence patency rates. This is a valuable technique for vascular surgeons that enables rescue of ischemic limbs under otherwise difficult circumstances.

Forced-air warming maintains normothermia during orthotopic liver transplantation.

We evaluated the efficacy of forced-air warming to maintain normothermia during liver transplantation. In a prospective, clinical trial 20 patients were randomly assigned to routine thermal management (circulating-water mattress set at 42 degrees C, intravenous fluid warming to 37 degrees C and passive insulation) or routine management with additional forced-air warming of head, chest, and arms. Core temperature was measured in the pulmonary artery. Morphometric and demographic characteristics were similar in each group, as was total administered fluid volume replacement. Core temperatures in each group decreased by about 0.6 degrees C during the first 70 min of anaesthesia and then by 0.9 degree C within 90 to 120 min in the patients given routine thermal management, but only by 0.4 degree C in those warmed with forced-air. Subsequently, core temperatures in the control group increased to only 35.7, SD 0.25 degree C whereas those in the patients given forced-air warming increased to 36.5, SD 0.2 degree C. Despite the relatively high ambient temperature, patients warmed only with a circulating-water mattress and passive insulation became hypothermic during surgery. In contrast, when forced-air warming was added to this routine thermal management, patients were normothermic at the end of surgery. Forced-air warming prevented intra-operative hypothermia during liver transplantation.

The role of routine angioscopy in vascular access surgery.

PURPOSE: The purpose of this retrospective study is to describe our techniques, review our experience, and determine the feasibility, safety, and role of the routine use of angioscopy during primary and revision vascular access surgery. METHODS: Between February 1991 and October 1993, intraoperative angioscopy was routinely performed in 84 consecutive operations (51 patients) for vascular access surgery. We reviewed the videotaped recordings of the angioscopic studies together with the clinical data according to a predetermined protocol. RESULTS: There were 43 primary procedures (36 autogenous arteriovenous fistulas and 7 bridge graft fistulas) and 41 revision procedures for failed vascular access (7 autogenous arteriovenous fistulas and 34 graft bridge fistulas). In 20.9% of the primary vascular access procedures, abnormal endoluminal findings were noted. Based on these findings, only one additional intervention was performed. In revision vascular access surgery, abnormal endoluminal findings were noted in 92.7%, resulting in additional surgical interventions in 65.9% of the procedures. In the revised synthetic bridge graft fistulas, stenosis of the midgraft (n = 9) as a result of needle insertion for dialysis was more common than at venous anastomosis (n = 4). Detection and correction of endoluminal abnormalities resulted in a 30-day patency of 66.6% as opposed to 33.3% when none was detected (p < or = 0.012, Fisher's exact test). CONCLUSIONS: Routine angioscopy is technically feasible and can be performed safely in anuric patients during vascular access surgery. It provides additional and useful intraoperative information that may significantly alter the surgical procedure. Routine angioscopy may also provide new insights into the pathophysiology of vascular access failure.

Role of angioscopy in reoperation for the failing or failed infrainguinal vein bypass graft.

The purpose of this retrospective study is to review our ongoing experience with the use of angioscopy during reoperation for failed or failing infrainguinal vein bypass grafts and define the role of angioscopy in the management of this clinically demanding patient group. All hospital records, arteriograms, and intraoperative angioscopic video recordings of 79 consecutive failed or failing grafts (76 patients) examined with angioscopy during reoperation between 1987 and 1993 were reviewed. Clinical and intraoperative data, comparison of the preoperative arteriogram and intraoperative angioscopic findings, and surgical decisions or interventions resulting from the additional angioscopic findings were collated and analyzed according to a predetermined protocol. Sixty-six additional angioscopic findings were noted during the 79 reoperations and resulted in 61 additional interventions and surgical decisions with salvage of all or part of the graft in 90.9% in the early (< 30 day) failed (group 1), 84.6% in the late (> 30 day) failed (group 2), and 90.3% in the late (> 30 day) failing grafts (group 3). The amount of residual thrombus within the graft, as assessed by angioscopy after all interventions, was the critical determinant for overall early graft patency (p < 0.001) and long-term patency for all the subgroups after reoperation (group 1, p < 0.001; group 2, p = 0.0016; and group 3, p = 0.0194). Intraoperative angioscopy has an important role in these challenging procedures. It provides additional and useful information that not only influences the conduct and extent of the reoperative surgery but may provide insights into the pathogenesis of graft failure.