4/23/2009. Vein Bypass Remains the Gold Standard AND We Can Improve Outcomes. Lower Extremity Revascularization Options: Key Factors to Consider

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1 Vein Bypass Remains the Gold Standard AND We Can Improve Outcomes Lower Extremity Revascularization Options: Key Factors to Consider General health of the patient Michael S. Conte MD Division of Vascular and Endovascular Surgery UCSF Medical Center Age, comorbidities Ambulatory status Severity of limb ischemia Anatomic distribution of disease Prior interventions Availability of autogenous vein Ipsilateral GSV > contralateral GSV > alternative veins UCSF Vascular Symposium

2 Infrainguinal Bypass Surgery Bypass with autogenous vein is the gold standard Results well documented in hundreds of reports: anecdotal > retrospective > randomized trials Versatile: results in complex situations (anatomic, patient related) well established Low mortality, good durability BUT there are limitations and risks: Wound and other complications Prolonged recovery Vein quality and availability; other alternatives inferior Surveillance and reintervention (30-50% over 5 years) Technically demanding procedures LE VEIN BYPASS AT BWH: Group Group Group Group Overall N (pt/proc) 218/ / / / /1642 M:F 74:26* 60:40 59:41 53:47* 60:40 Age (mean/med) 64/65* 66/67 69/70 68/70* 67/68 Tissue loss (%) 31* 35* 37 53* 41 DM (%) 37* 36* 36 52* 42 Prior CABG (%) 5.5* 4.8* * 12.5 Renal insuff (%) 6.3* 6.8* * 10.7 Ectopic/comp (%) 5* 4.8* 18 19* 13 Tibial/pedal (%) 23* 45* 56 68* 52 * p<0.001 vs Group 4 2

3 AUTOGENOUS VEIN BYPASS: BWH Primary graft patency N=1,642 vein bypasses Conte MS et al. Ann Surg 2001 Ann Surg 2001;233: AUTOGENOUS VEIN BYPASS: BWH Secondary graft patency PREVENT III: A Snapshot of Limb Salvage Bypass Surgery Randomized, placebo-controlled trial of E2F-decoy ODN for the prevention of vein graft failure Patients undergoing autogenous vein bypass surgery for treatment of CLI Broadly inclusive study population 83 North American sites (academic and community hospitals) including 5 sites in Canada Enrollment initiated December 2001 Completed enrollment September 2003 (N=1404) One year follow-up Conte MS, et al. Vasc Endovasc Surg 2005 Conte MS, et al. J Vasc Surg

4 Edifoligide (n=707) Placebo (n=697) Edifoligide (n=707) Placebo (n=697) Age (yr) Mean ± SD 68.7+/ / Male 454 ( 64.2%) 443 ( 63.6%) Caucasian 526 ( 74.4%) 491 ( 70.4%) Black 116 (16.4%) 133 (19.1%) Asian 3 (0.4%) 7 (1.0%) Hispanic 53 (7.5%) 54 (7.7%) Other 9 (1.3%) 12 (1.7%) CLI criterion- Rest Pain 184 (26.0%) 169 (24.2%) Non-healing ulcer 272 (38.6%) 280 (40.2%) Gangrene 247 (34.9%) 246 (35.3%) ABI- Mean/Median 0.5/ /0.4 Comorbidities Hypertension 577 (81.6%) 569 (81.6%) Diabetes 461 (65.2%) 439 (63.0%) CAD 338 (47.8%) 336 (48.2%) CVD 144 (20.4%) 140 (20.1%) Smoking 520 (73.5%) 513 (73.6%) Dyslipidemia 393 (55.6%) 373 (53.5%) Dialysis 84 (11.9%) 86 (12.3%) Prior leg ravasularization Inflow procedure 146 (20.7%) 147 (21.1%) Infrainguinal (either limb) 190 (26.9%) 193 (27.7%) Conduit Type Single segment GSV, reversed 371 (52%) 360 (52%) Single segment GSV, nonreversed 207 (29%) 193 (28%) Spliced vein 95 (13%) 110 (16%) Single segment non-gsv 34 (5%) 34 (5%) Vein diameter < 3mm 36 (5.1%) 49 (7.0%) Total high risk conduits 158 (22.3%) 181 (26.0%) Re-do bypass 102 (14.4%) 94 (13.5%) Proximal anastomosis Common femoral 352 (50%) 335 (48%) Superficial femoral 164 (23%) 183 (26%) Deep femoral 28 (4%) 27 (4%) Popliteal 126 (18%) 114 (16%) Other 37 (5%) 38 (5%) Distal anastomosis Popliteal, above knee 69 (10%) 76 (11%) Popliteal, below knee 161 (23%) 151 (22%) Anterior tibial 106 (15%) 113 (16%) Posterior Tibial 136 (19%) 154 (22%) Peroneal 132 (19%) 107 (15%) Pedal/plantar 80 (11%) 86 (12%) Other 23 (3%) 10 (1%) Perioperative (30 day) complications Summary of Outcomes (1-year; all are %) Edifoligide Placebo Total Total major morbidity 124 (17.3%) 126 (17.9%) 250 (17.6%) Cardiac or resp arrest 12 (1.7%) 9 (1.3%) 21 (1.5%) DVT 6 (<1.0%) 8 (1.1%) 14 (<1.0%) Death 20 (2.8%) 18 (2.6%) 38 (2.7%) Graft occlusion 30 (4.2%) 43 (6.2%) 73 (5.2%) Major amputation 13 (1.8%) 12 (1.7%) 25 (1.8%) Pneumonia 10 (1.4%) 14 (2.0%) 24 (1.7%) Pulmonary embolism 1 (<1.0%) 0 (0.0%) 1 (<1.0%) Stroke or TIA 12 (1.7%) 8 (1.1%) 20 (1.4%) Major wound complication 38 (5.3%) 30 (4.3%) 68 (4.8%) Dehiscence 3 (<1.0%) 9 (1.3%) 12 (<1.0%) Infection 25 (3.5%) 15 (2.1%) 40 (2.8%) Necrosis 9 (1.3%) 6 (<1.0%) 15 (1.1%) Edifoligide Placebo P Protocol-specified endpoints: Primary trial endpoint All clinical failures Freedom from CSS Amp/reint-free survival Conventional endpoints: Primary patency Primary assisted patency Secondary patency Limb salvage Survival Graft hemorrhage 3 (0.4%) 4 (0.6%) 7 (0.5%) 4

5 Subgroup analyses in PIII Conduit quality Most important single factor Diabetes No observed negative impact on patency Amputation-free survival is reduced DOGs and graft length Popliteal inflow and shorter length grafts performed better Schanzer AS et al J Vasc Surg 2007 (In press) PREVENT III: Optimal Conduit Schanzer AS et al J Vasc Surg 2007 (In press) N= 604 bypasses (43% of study population) completed with a single segment GSV, diameter > 3.5 mm 30 day failure 1.7% One year results PP 72% SP 87% Limb salvage 91% Importance of conduit assessment and quality Schanzer AS et al J Vasc Surg 2007 (In press) 5

6 Subgroup analyses in PIII- Diabetes has no effect on vein graft patency QOL outcomes in PREVENT III Beneficial effects of limb revascularization on QOL have been questioned Prior single center studies have shown poor functional status at baseline, some improvement post LEB PREVENT III included VascuQol at 3 and 12 mos Mean global scores increased significantly at 3 and 12 mos (p<.0001) Benefit extended across all domains Graft-related events and diabetes had a negative impact on QoL improvement at 12 months (still +) Nguyen LL, Moneta GL, Conte MS et al. J Vasc Surg : Race and Gender Disparities Incidence of WC 39%; 11% considered serious (SWC) 15% of SWC required surgical intervention Propensity-score adjusted for 16 covariates AAM higher rate of 30-day graft failure (OR 2.96) AA, esp AAF increased risk for loss of PAP/SP (HR 1.92/1.96) AA, esp AAF increased risk for limb loss (HR 2.04) MV predictors : postoperative oral anticoagulation (OR 1.49), female gender (OR 1.38) SWC inc risk for limb loss (HR 1.96), mortality (HR 1.62) SWC a/w lower QoL at 3 months postop, greater resource utilization (LOS, rehospitalizations) 6

7 Amputation-Free Survival following vein bypass for CLI: Developing Risk Prediction Models Lower extremity revascularization for advanced PAD: major surgical challenges COVARIATES DF β coefficient Integer score HR (95% CI) P-Value Age 75 years ( ) Hematocrit < (1.11, 2.34) History of advanced CAD (1.05, 1.88) Dialysis (1.97, 3.99) < CLI criterion (1.43, 3.44) Risk categories (based upon integer score) and estimated 1 year amputation-free survival 1. Vein graft failure 2. Lack of adequate autogenous conduit/ small caliber prosthetic solution Amputation-Free Survival Low (<4) Medium (4-8) High (>8) Risk category (integer score) Derivation Set Validation Set 3. Wound morbidity Schanzer A et al J Vasc Surg 2008;48: Prevention of Vein Graft Failure: Potential Strategies Timing Causes Strategies Early Technical factors Technical Thrombophilia Antithrombotics Mid-term VG hyperplasia Drug/molecular Rx?Remodeling?Inflammation Anti-proliferative Anti-inflammatory Antithrombotic Late Progressive Athero Lipid lowering Anti-inflammatory Anti-thrombotics Risk factor mod. Key Technical Factors Conduit assessment and handling Selection of inflow/outflow sites Tunneling errors Management of coagulation Completion assessment 7

8 Technical factors:conduit Conduit assessment and handling Avoid small, sclerotic segments Spliced (good quality) vein better than retaining a poor quality segment Minimize harvest trauma and ischemia Careful, complete valve lysis Spliced vein anastomoses Preparation of ectopic/spliced vein conduits Technical factors-arteries Valve lysis for nonreversed segments Venovenostomy Selection of inflow/outflow sites Distal origin grafts quite useful esp. in diabetics Don t compromise on the target vessel Dealing with calcification Tourniquet control often useful % Cumulative Patency Autogenous DOGs Diabetic Secondary Patency Non-Diabetic Secondary Patency Time (months) Reed JVS 2002;35:48 8

9 Antithrombotic therapy ASA (325 mg/day) periop and long term No safety concern with regional anesthesia techniques Moderate-dose heparin (70 u/kg) intraop Redose prn to maintain ACT s Protamine reversal rarely employed Role of plavix undefined Role of coumadin controversial BOA versus VA Cooperative study results Primary role in high risk grafts/patients Postoperative Management Graft surveillance and reintervention strategies Medical management Antithrombotic therapy Statins and other lipid-lowering agents Smoking cessation Reintervention for Graft Stenosis Maintains secondary patency, reduce need and complexity of re-do bypass surgery Revision of failing grafts far superior to attempted salvage of thrombosed grafts Timing of initial lesion and graft anatomy influence durability of the revision Reintervention for Graft Stenosis Roles for endovascular vs. open surgical revision Early lesions (< 3mos), longer lesions, occlusions do poorly with isolated endovascular approach Unclear role for stents at this time Patch angioplasty, jump/interposition options Nguyen LL eet al J Vasc Surg 2004;40: Berceli SA et al J Vasc Surg 2007;46:

10 Prevention of Vein Graft Failure Technical, technical, technical Antithrombotic therapy Graft surveillance paramount Medical mgmt of athero risk factors Possible role for anti-inflammatory Rx Evolution of molecular and genetic therapies Further research on mechanisms, risk factors needed Infrainguinal bypass: pros and cons Excellent durability in diverse patients and anatomic circumstances For many patients with CLI, a well-executed vein graft is the single best chance to achieve durable limb preservation But there are significant costs and limitations How can we improve? Define quality standards for LE revascularization Technical competence/training- a concern in the endo era Define optimal medical therapy Appropriate patient selection and timing Wound management and less invasive surgical approaches Better predictive markers/optimize surveillance Better alternative conduits New therapies to prevent graft failure 10