Faculty Bibliography

The Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) has been used to support the equivalence of carotid artery stenting (CAS) and carotid endarterectomy (CEA) in the treatment of carotid stenosis in both symptomatic and asymptomatic patients. This inclusion of two different forms of the disease decreased the power and significance of the CREST results and weakened the trial. Other flaws in CREST were the equal weighting of mostly minor myocardial infarctions (MIs) with strokes and death in the peri-procedural, composite 'end' point, but not in the 4-year, long-term 'end' point. Although CAS was associated with 50% fewer peri-procedural MIs compared with CEA, there were >2.5-fold more MIs after CAS than CEA at 4 years. The 4-year MI rate, however, was not a component of the primary 'end' point. Additionally, although the initial CREST report indicated that there was no difference in the outcomes of CAS and CEA according to symptomatic status or sex, subsequent subgroup analyses showed that CAS was associated with significantly higher stroke and death rates than CEA in symptomatic patients, in females and in individuals >/= 65 years of age. The present article will examine these and other flaws and the details of CREST's results derived from the trial's preplanned subanalyses to show why the claims that CREST demonstrates equivalence of the two therapeutic procedures are unjustified.

OBJECTIVE: We report our experience with the treatment of femoral artery aneurysms (FAAs) under local anaesthesia with limited dissection, using endografts to facilitate the proximal anastomosis and some distal anastomoses. METHOD: Between January 2006 and December 2010, six males, mean age 72 years (range, 65-80 years) with FAAs were treated at the University Hospital of Zurich. All operations were performed under local anaesthesia with analgosedation, except for one performed under spinal anaesthesia. After limited dissection and puncture of the anterior wall of the FAA, a sheath and a self-expanding endograft were introduced over a guide wire and with fluoroscopy they were guided intraluminally into the proximal normal neck of the FAA and deployed. Proximal arterial control was achieved with a balloon catheter introduced through the endograft. Then the FAAs were opened and distal arterial control is obtained with balloon catheters. The distal end of the stent graft was then sutured to the normal-sized distal arteries or to stent grafts placed within them. RESULTS: Of the six FAAs, four were true and two were false anastomotic aneurysms. Mean FAA diameter was 5.0 cm (range, 3.0-6.5 cm). Four patients also had aneurysmal involvement of the external iliac artery, one patient also had deep femoral aneurysms, but deep femoral circulation was always preserved. In three of the patients, the distal anastomosis was created to the femoral artery bifurcation, in two patients to the deep femoral artery when the superficial femoral artery (SFA) was chronically occluded and in one patient to the SFA. Immediate technical success was achieved in all six patients, and graft patency was observed from 9 to 48 months (mean 29 months). There were no amputations, complications or deaths. CONCLUSION: This technique for repair of FAAs can be performed under local anaesthesia, minimises dissection and complications and simplifies exclusion of these lesions. It is of particular value in high-risk patients with large FAAs.

The optimal treatment of patients facing imminent amputation after multiple (>/=2) failed prior ipsilateral bypasses is unclear. We analyzed a group of patients undergoing multiple lower extremity bypasses for limb salvage to assess the utility of attempting multiple revascularizations. From 1990 to 2005, 105 revascularization procedures were performed in 55 limbs of 54 patients with imminent limb-threatening lower extremity ischemia after failure of >/=2 prior infrainguinal bypasses in the same leg. Fifty-five operations were the third procedure (Group A) and 50 operations were the fourth or more (Group B). We compared primary/secondary patency and limb salvage rates by Society for Vascular Surgery criteria. Limb salvage rates did not differ between patients undergoing a third bypass and those undergoing four or more bypasses at one year (62 versus 65%, NS) or at three years (58 versus 61%, NS). Secondary patency was not different between groups (76 versus 76%, P = NS) at one and three years (71 versus 70%, NS). Primary patency also did not differ between the two groups, at one year (24 versus 35%, NS), or at three years (11 versus 15%, NS). No differences were observed in morbidity and mortality rates between the groups. In conclusion, the likelihood of success of repetitive limb revascularization was unrelated to the number of previous failures. The expected incremental failure rate with each successive bypass was not found. These results, coupled with the three-year limb salvage rate of over 50% in patients who otherwise would have required amputation, lend support to aggressive use of limb revascularization in selected patients even after two or more failed bypasses.

The results of good randomized controlled trials (RCTs) published in leading peer-reviewed journals have been deemed the best possible basis for good medical practice. However, several limitations may decrease their value. These include flaws and weaknesses in the design and the timeliness of RCTs. Progress in a treatment method or control arm may invalidate a trial. So too can defects in patient selection, physician competence, randomization, applicability, end points, and the population being studied. Idiosyncratic flaws can also invalidate an RCT. Examples of these flaws and weaknesses are presented. Another problem with articles describing RCTs is the potential for the conclusions of the trial report to be misleading because of error or bias. This plus subsequent misinterpretation of the trial results or conclusions by others can make the effect of the trial misleading with an unintended detrimental result on medical practice. Guidelines based on such errors or bias-based conclusions and misinterpretations can further compound the problem. This article provides examples of misleading conclusions and/or misinterpretations (spinning) of trial results in articles describing RCTs in leading journals. All physicians should recognize these value-limiting processes so that RCTs can be evaluated adequately and fairly. In that way, they can be used along with good physician judgment to optimize the care delivered to individual patients and to society at large.

BACKGROUND: Prosthetic grafts for lower-extremity bypass have limited patency compared with autologous vein grafts. Precuffed expanded polytetrafluoroethylene (ePTFE) grafts alter the geometry of the distal hood to improve patency. This study reports the authors' long-term results on the use of precuffed ePTFE grafts for infrainguinal bypasses in patients with arterial occlusive disease and compares these with results of reversed great saphenous vein grafts (rSVG). METHODS: A retrospective review of billing codes identified 101 polytetrafluoroethylene (PTFE) and 47 rSVG bypasses performed over a 6-year period. Femoral to below-knee popliteal and femoral to tibial bypasses were analyzed. Data collected consisted of risk factors, Rutherford classification, bypass inflow and outflow, runoff vessels, patency, amputation, and death. Primary end points consisted of primary, assisted-primary, and secondary patency along with limb salvage. RESULTS: Mean age of the patients was 76 years in the PTFE group and 69.8 years in the rSVG group. For femoral to below-knee popliteal bypasses, primary patency at 1, 3, and 5 years in the PTFE group was 76.9%, 48.7%, and 43.3%, respectively, compared with 77.1%, 77.1%, and 77.1%, respectively, in the rSVG group (P = 0.225). Secondary patency was 89.2%, 70.9%, and 50.6% in the PTFE group compared with 84.4%, 84.4%, and 84.4% in the rSVG group (P = 0.269). Limb salvage was similar in the PTFE compared with the rSVG group (97.7%, 90.5%, and 79.4% vs. 83.3%, 83.3%, and 83.3%; P = 0.653). For femoral to tibial bypasses, primary patency in the PTFE group at 1, 3, and 5 years was 57.1%, 40.4%, and 22.1%, respectively, compared with 67.4%, 67.4%, and 50.6%, respectively, for the rSVG group (P = 0.246). Secondary patency was 75.5%, 44.9%, and 22.7% in the PTFE group compared with 91.8%, 91.8%, and 52.5% in the rSVG group (P = 0.022). Limb salvage at 1, 3, and 5 years was 79.2%, 55.7%, and 55.7%, respectively, in the PTFE group compared with 96.4%, 96.4%, and 64.3%, respectively, in the rSVG group (P = 0.046). CONCLUSIONS: Precuffed ePTFE grafts demonstrate similar 1-year patency to that of rSVG. However, mid- and long-term patency is reduced compared with saphenous vein grafts (SVG), especially to tibial targets. PTFE grafts to the popliteal demonstrate limb salvage rates similar to those of SVG. In the tibial vessels, limb salvage rates for PTFE grafts are significantly worse compared with SVG.

Endovascular aneurysm repair is being used increasingly to treat ruptured abdominal aortic aneurysms (RAAAs). Approximately 25% of RAAAs undergo complete circulatory collapse before or during the procedure. Patient survival depends on obtaining and maintaining supraceliac balloon control until the endograft is fully deployed. This is accomplished with a sheath-supported compliant balloon inserted via the groin contralateral to the side to be used for insertion of the endograft main body. After the main body is fully deployed, a second balloon is placed within the endograft, and the first balloon is removed so that extension limbs can be placed in the contralateral side. A third balloon can be placed via the contralateral side and ipsilateral extensions deployed as necessary. This technique of supraceliac balloon control is important to achieving good outcomes with RAAAs. In addition to minimizing blood loss, this technique minimizes visceral ischemia and maintains aortic control until the aneurysm rupture site is fully excluded.

BACKGROUND: CMI is caused by chronic occlusive disease of mesenteric arteries. In such an uncommon disease, clear recommendations are strongly needed. Unfortunately, treatment options for symptomatic CMI are still controversial and no guidelines exist. METHODS: A systematic literature review of the last 25-years was conducted through MEDLINE, Embase, and Cochrane Review/Trials register to identify studies reporting on CMI treatment with more than 10 patients. Primary outcomes were perioperative mortality and morbidity rates. Secondary outcomes were survival rates, primary and secondary patency rates, vessels treated, CMI recurrence, follow-up (FU), technical success (TS), and in-hospital length of stay (InH-LOS). Patients were divided into endovascular treatment (ET) or open treatment (OT) groups. Subsequently, primary and secondary outcomes were analyzed by study publication year for the interval periods 1986-2000 ("A") and 2001-2010 ("B"). Differences were assessed using the t-test and the chi(2) test. RESULTS: Forty-three articles with 1,795 patients were included. Perioperative mortality and morbidity rates were lower in the ET group. No difference in survival rate was observed. Primary and secondary patencies were superior in the OT group. A greater number of vessels were revascularized in the OT group. CMI recurrence was more frequent in the ET group. FU was longer in the OT group. TS was superior in the OT group and InH-LOS was shorter in the ET group. A higher number of patients were treated by ET in the period "A." No differences in mortality and morbidity were observed between period "A" and "B" in ET and OT groups. CONCLUSIONS: Considering the lower periprocedural mortality and morbidity after ET, this approach should be considered as the first treatment option in most CMI patients, especially in those with severe malnutrition. Primary OT should be restricted to cases that do not qualify for ET or good surgical risk patients with long life expectancy. Considering better long-term results of OT, ET treatment should be considered as a bridge therapy to OT in some patients requiring retreatment if ET does not preclude subsequent OT.

OBJECTIVE: This study assessed the risk of left subclavian artery (LSA) coverage and the role of revascularization in a large population of patients undergoing thoracic endovascular aortic aneurysm repair. METHODS: A retrospective multicenter review of 1189 patient records from 2000 to 2010 was performed. Major adverse events evaluated included cerebrovascular accident (CVA) and spinal cord ischemia (SCI). Subgroup analysis was performed for noncovered LSA (group A), covered LSA (group B), and covered/revascularized LSA (group C). RESULTS: Of 1189 patients, 394 had LSA coverage (33.1%), and 180 of these patients (46%) underwent LSA revascularization. In all patients, emergency operations (9.5% vs 4.3%; P = .001), renal failure (12.7% vs 5.3%; P = .001), hypertension (7% vs 2.3%; P = .01), and number of stents placed (1 = 3.7%, 2 = 7.4%, >/=3 = 10%; P = .005) were predictors of SCI. History of cerebrovascular disease (9.6% vs 3.5%; P = .002), chronic obstructive pulmonary disease (9.5% vs 5.4%; P = .01), coronary artery disease (8.5% vs 5.3%; P = .03), smoking (8.9% vs 4.2%) and female gender (5.3% men vs 8.2% women; P = .05) were predictors of CVA. Subgroup analysis showed no significant difference between groups B and C (SCI, 6.3% vs 6.1%; CVA, 6.7% vs 6.1%). LSA revascularization was not protective for SCI (7.5% vs 4.1%; P = .3) or CVA (6.1% vs 6.4%; P = .9). Women who underwent revascularization had an increased incidence of CVA event compared with all other subgroups (group A: 5.6% men, 8.4% women, P = .16; group B: 6.6% men, 5.3% women, P = .9; group C: 2.8% men, 11.9% women, P = .03). CONCLUSIONS: LSA coverage does not appear to result in an increased incidence of SCI or CVA event when a strategy of selective revascularization is adopted. Selective LSA revascularization results in similar outcomes among the three cohorts studied. Revascularization in women carries an increased risk of a CVA event and should be reserved for select cases.

INTRODUCTION/AIM: We reviewed the literature for studies evaluating the effects of statins on vascular patients undergoing open surgical or endovascular procedures. METHODS: MEDLINE was searched using the search terms "statins and vascular surgery", "statins and endovascular procedures", "statins and perioperative effects" and "statins and postoperative complications". RESULTS: Preoperative statin use is associated with lower perioperative/periprocedural death, myocardial infarction and stroke rates. Statins may also reduce postoperative complications as well as hospitalization rates and costs. Statins reduce the incidence of postoperative/postprocedural renal insufficiency and help the earlier recovery of complete kidney function in vascular patients. A loading dose of statins prior to a procedure may be associated with improved cardiovascular outcomes. CONCLUSIONS: Statins are associated with several beneficial actions in patients undergoing open surgical or endovascular procedures. Nevertheless, statin use in vascular patients still remains underutilized and suboptimal. Ideally, statins should be initiated a minimum of 2 weeks before the procedure. Extended-release formulas may be preferable perioperatively to cover the first 1-2 days after the procedure when oral intake may not be feasible. Statins should be administered to all vascular disease patients, whether they are managed conservatively or are undergoing open surgical or endovascular procedures.