Role of aortic stent graft oversizing and barb characteristics on folding.
J Vasc Surg. 2012 Feb 1;
Authors: Lin KK, Kratzberg JA, Raghavan ML
Abstract
OBJECTIVE: To evaluate folding in infrarenal stent grafts in relation to oversizing, barb angle, and barb length using computed tomography images of stent grafts deployed in explanted bovine aortas. METHODS: Computed tomography data from an in vitro investigation on the effect of oversizing of 4% to 45% (n = 19), barb length of 2 to 7 mm (n = 11), and barb angle of 10° to 90° (n = 7) on device fixation were examined for instances of folding. Folding was classified as circumferential or longitudinal and quantified on an ordinal scale based on codified criteria. Cumulative fold ranking from 0 (no fold) to 6 (two severe folds) for each deployment was used as the measure of folding observed. RESULTS: Of the 37 cases, cumulative mean ± standard deviation fold ranking for stent grafts oversized >30% (n = 5) was significantly greater than the rest (3.4 ± 1.7 vs 0.5 ± 1.2, respectively; Mann-Whitney U test; P < .005). When barb length was varied from 2 to 7 mm (oversizing held at 10%-20%), folding was noted in one of 11 cases. Similarly, when barb angle was varied from 0° (vertical) to 90° (horizontal), folding was not noted in any of the seven cases. The pullout force was not significantly different between stent grafts with and without folding (5.4 ± 1.95 vs 5.12 ± 1.89 N, respectively; P > .5). At least one instance of folding was noted in the seven of seven (100%) stent grafts with oversizing >23.5% and in only five of 30 (14%) stent grafts with oversizing <23.5%. CONCLUSIONS: Stent graft folding was prevalent when oversized >30%. Large variations in barb length and angle did not aggravate folding risk when oversized within the recommended range of 10% to 20%.
PMID: 22305271 [PubMed - as supplied by publisher]
Elective sac perfusion to reduce the risk of neurologic events following endovascular repair of thoracoabdominal aneurysms.
J Vasc Surg. 2012 Feb 1;
Authors: Harrison SC, Agu O, Harris PL, Ivancev K
Abstract
Spinal cord ischemia (SCI) is a catastrophic complication of thoracoabdominal aortic aneurysm (TAAA) repair. This article describes our early experience with a technique for maintaining perfusion of segmental vessels (intercostals and lumbars) in the early postoperative period after endovascular repair of a TAAA, with “sac perfusion branches” added to custom-made stent grafts. These are closed 7 to 10 days after the first procedure to complete exclusion of the aneurysm. We have used this technique in 10 patients with type II TAAAs. One developed monoparesis of the right leg during a period of hypotension secondary to a cardiac event and died within 30 days. Two patients developed lower limb weakness after closure of the perfusion branches, both with full recovery. Controlled perfusion of segmental vessels with perfusion branches is feasible and may be a useful adjunct to prevent SCI, providing protection to spinal cord perfusion during the immediate postoperative period when risk of SCI is greatest.
PMID: 22305272 [PubMed - as supplied by publisher]
Long-term results for primary bypass versus primary angioplasty/stent for intermittent claudication due to superficial femoral artery occlusive disease.
J Vasc Surg. 2012 Jan 31;
Authors: Siracuse JJ, Giles KA, Pomposelli FB, Hamdan AD, Wyers MC, Chaikof EL, Nedeau AE, Schermerhorn ML
Abstract
BACKGROUND: Percutaneous transluminal angioplasty ± stent (PTA/S) and surgical bypass are both accepted treatments for claudication due to superficial femoral artery (SFA) occlusive disease. However, long-term results comparing these modalities for primary intervention in patients who have had no prior intervention have not been reported. We report our results with 3-year follow-up. METHODS: We reviewed all lower extremity bypass procedures at Beth Israel Deaconess Medical Center from 2001 through 2009 and all PTA/S performed from 2005 through 2009 for claudication. We excluded all limb salvage procedures and included only those that were undergoing their first intervention for claudication due to SFA disease. We recorded patient demographics, comorbidities, perioperative medications, TASC classification, and runoff. Outcomes included complications, restenosis, symptom recurrence, reinterventions, major amputation, and mortality. RESULTS: We identified 113 bypass grafts and 105 PTA/S of femoral-popliteal lesions without prior interventions. Bypasses were above the knee in 62% (45% vein) and below the knee in 38% (100% vein). Mean age was 63 (bypass) versus 69 (PTA/S; P < .01). Mean length of stay (LOS) was 3.9 versus 1.2 days (P < .01). Bypass grafts were used less for TASC A (17% vs 40%; P < .01) and more for TASC C (36% vs 11%; P < .01) and TASC D (13% vs 3%; P < .01) lesions. There were no differences in perioperative (2% vs 0%; not significant [NS]) or 3-year mortality (9% vs 8%; NS). Wound infection was higher with bypass (16% vs 0%; P < .01). None involved grafts. Bypass showed improved freedom from restenosis (73% vs 42% at 3 years; hazard ratio [HR], 0.4; 95% confidence interval [CI], .23-.71), symptom recurrence (70% and 36% at 3 years; HR, 0.37; 95% CI, .2-.56), and freedom from symptoms at last follow-up (83% vs 49%; HR, 0.18; 95% CI, .08-.40). There was no difference in freedom from reintervention (77% vs 66% at 3 years; NS). Multivariable analysis of all patients showed that restenosis was predicted by PTA/S (HR, 2.5; 95% CI, 1.4-4.4) and TASC D (HR, 3.7; 95% CI, 3.5-9) lesions. Recurrence of symptoms was similarly predicted by PTA/S (HR, 3.0; 95% CI, 1.8-5) and TASC D lesions (HR, 3.1; 95% CI, 1.4-7). Statin use postoperatively was predictive of patency (HR, 0.6; 95% CI, .35-.97) and freedom from recurrent symptoms (HR, 0.6; 95% CI, .36-.93). CONCLUSIONS: Surgical bypass for the primary treatment of claudication showed improved freedom from restenosis and symptom relief despite treatment of more extensive disease, but was associated with increased LOS and wound infection. Statins improved freedom from restenosis and symptom recurrence overall.
PMID: 22301210 [PubMed - as supplied by publisher]
First results of clampless distal anastomosis in peripheral vascular bypass with LeGoo, a thermoreversible polymer.
J Vasc Surg. 2012 Jan 31;
Authors: Kretz B, Steinmetz E, Brenot R, Bouchot O
Abstract
BACKGROUND: We report our initial experience with LeGoo (Pluromed Inc, Woburn, Mass), a temporary thermoreversible occlusive gel, in peripheral vascular revascularization. METHODS: Between 2007 and 2010, LeGoo was used to occlude target vessels during bypass surgery in 14 patients who required infrainguinal revascularization. RESULTS: Proximal occlusion of the target vessel was obtained with a mean quantity of 0.25 mL of LeGoo. Distal occlusion of the vessel was obtained with a mean quantity of 0.28 mL. One injection of LeGoo was sufficient to prevent backbleeding in 11 of 14 patients. The mean occlusion time was 13.4 ± 3.3 minutes. An injection of saline through the graft or better directly into the arteries was used to dissolve the gel. For our first case, a Fogarty catheter was used to remove residual gel from the anterior tibial artery. CONCLUSIONS: LeGoo gel can be used to stop blood flow in small-bore arteries in the lower limbs to allow anastomoses to be performed.
PMID: 22301211 [PubMed - as supplied by publisher]
Duplex velocity criteria for native celiac/superior mesenteric artery stenosis vs in-stent stenosis.
J Vasc Surg. 2012 Jan 31;
Authors: Aburahma AF, Mousa AY, Stone PA, Hass SM, Dean LS, Keiffer T
Abstract
BACKGROUND: Duplex velocity criteria (DVC) to identify in-stent celiac artery (CA) and superior mesenteric artery (SMA) stenosis is not well defined. Only one study has been published which concluded that DVC for native SMA stenosis overestimated stenosis in stented SMAs. The purpose of this study was to analyze DVC in detecting CA/SMA in-stent stenosis (ISS). METHODS: Forty-three patients with 62 stents (32 SMAs and 30 CAs), who had concurrent postoperative duplex ultrasound scan and angiograms for significant ISS by DVC were analyzed. A receiver operator curve (ROC) analysis was used to determine optimal DVC (peak systolic velocity [PSV], end-diastolic velocity [EDV], and CA or SMA/aortic systolic ratios) for detecting ≥50% and ≥70% ISS. These were compared to duplex velocities obtained from 97 native CAs and 74 native SMAs with ≥50% stenosis done in the same study period. RESULTS: The mean stented celiac PSV (cm/s), EDV, and systolic ratio for ≥50% ISS were 447, 136, and 7.1 vs 379, 104, and 5.2 for ≥50% native stenosis (P = .067, .106, and < .01). The mean stented SMA PSV, EDV, and ratio for ≥50% ISS were 410, 114, and 6.2 vs 405, 76, and 2.0 for ≥50% native stenosis (P = .885, .037, and < .0001). The PSV cutpoints for detecting ≥50% SMA ISS was 325 cm/s (sensitivity 89%, specificity 100%, and overall accuracy 91%) vs 295 cm/s for ≥50% native SMA and for ≥70% SMA ISS was 412 (sensitivity 100%, specificity 95%, and overall accuracy 97%) vs 400 for native stenosis. The PSV cutpoints for ≥50% CA ISS was 274 cm/s (sensitivity 96%, specificity 86%, and overall accuracy 93%) vs 240 cm/s for ≥50% native stenosis and for ≥70% CA ISS was 363 (sensitivity 88%, specificity 92%, and overall accuracy 90%) vs 320 cm/s for native stenosis (sensitivity 80, specificity 89%, and overall accuracy 85%). ROC analysis also showed that both PSVs and EDVs were equal predictors for SMA and CA ≥50% and ≥70% ISS. For ≥50% SMA ISS, the area under the curve (AUC) for PSV equals 0.91, EDV = 0.81, P = .341. For CA, PSV, AUC = 0.99, EDV = 0.88, P = .063. CONCLUSION: There is a tendency toward higher velocities in stented CA/SMAs in comparison to native arteries. Caution must be exercised in using duplex velocity cutoffs for native CA/SMA stenosis for stented CA/SMA. Further prospective validation studies are needed.
PMID: 22301212 [PubMed - as supplied by publisher]
The chimney graft technique for preserving visceral vessels during endovascular treatment of aortic pathologies.
J Vasc Surg. 2012 Jan 10;
Authors: Moulakakis KG, Mylonas SN, Avgerinos E, Papapetrou A, Kakisis JD, Brountzos EN, Liapis CD
Abstract
OBJECTIVE: Patients with juxtarenal, pararenal, or thoracoabdominal aneurysms require complex surgical open repair, which is associated with increased mortality and morbidity. The “chimney graft” or “snorkel” technique has evolved as a potential alternative to fenestrated and side-branched endografts. The purpose of this study is to review all published reports on chimney graft (CG) technique involving visceral vessels and investigate the safety and efficacy of the technique. METHODS: Studies were included in the present review if visceral revascularization during endovascular treatment of aortic pathologies was achieved via a CG implantation. Reports on the chimney technique for aortic arch branches revascularization were excluded. A multiple electronic health database search was performed on all articles published until April 2011. RESULTS: The electronic literature search yielded 15 reports that fulfilled the inclusion criteria. A total of 93 patients (81.3% male; mean age, 71.9 ± 0.9 years) were analyzed. In 77.4% of the patients, the CG procedure was applied for the treatment of abdominal aortic aneurysms. Out of the 93 patients, 24.7% were operated on in an urgent setting (symptomatic or ruptured aneurysm). A total of 134 CGs were implanted: 108 to the renal arteries, 20 to the superior mesenteric artery, five to the celiac trunk, and one to the inferior mesenteric artery. In 57 patients, a single CG was deployed; in 32 patients, two CGs; in three patients, three CGs; and in one patient, four CGs were deployed. Ninety-four percent of CGs were directed proximally, whereas 6.0% were directed caudally. Primary technical success was achieved in all patients. A total of 13 patients (14.0%) developed a type I endoleak. Three were detected and treated intraoperatively. Postoperatively, 10 type I endoleaks were revealed, four of which required secondary intervention. During a mean follow-up period of 9.0 ± 1.0 months, 131 of 134 (97.8%) CGs remained patent. Two CGs to the renal arteries and one to the superior mesenteric artery occluded. Postoperatively, 11.8% of patients suffered renal function impairment and 2.1% a myocardial infarction. Ischemic stroke presented in 3.2% of patients. The 30-day in-hospital mortality was 4.3%. CONCLUSIONS: The role of the chimney technique in the management of complex abdominal aortic aneurysms is still unclear. This technique has relatively good results, considering the anatomic limitations of the aortic neck. However, long-term endograft durability and proximal fixation remains a significant concern. Thus, there is a reasonable hesitation to embrace the method for widespread use in the absence of long-term data.
PMID: 22236883 [PubMed - as supplied by publisher]
The importance of antegrade completion angiography in aortobifemoral bypass limb revision.
J Vasc Surg. 2012 Jan 10;
Authors: Helmick RA, Mesh CL
Abstract
Aortobifemoral bypass is a durable arterial reconstruction with well-defined failure modes. Management of graft limb thrombosis requires restoration of inflow and correction of any causative outflow lesions. Successful, minimally invasive inflow restoration with catheter thrombectomy can become problematic if assessment of technical adequacy is deficient or reveals causal lesions within the graft body. We describe a case illustrating the potential shortfall of retrograde graft limb completion angiography in depicting neointimal flaps, the benefit of antegrade angiography in depicting these flaps, and a novel utilization of a standard endovascular method to correct flaps that involve the graft body.
PMID: 22236884 [PubMed - as supplied by publisher]
Results of carotid artery stenting with distal embolic protection with improved systems: Protected Carotid Artery Stenting in Patients at High Risk for Carotid Endarterectomy (PROTECT) trial.
OBJECTIVE: The Protected Carotid Artery Stenting in Patients at High Risk for Carotid Endarterectomy (PROTECT) study was performed to evaluate the safety and effectiveness of two devices for carotid artery stenting (CAS) in the treatment of carotid artery stenosis in patients at high risk for carotid endarterectomy (CEA): (1) a new embolic protection device, the Emboshield Pro (Abbott Vascular, Abbott Park, Ill), using the periprocedural composite end point of 30-day death, stroke, and myocardial infarction (DSMI), and (2) a carotid stent in conjunction with an embolic protection device (EPD) using the DSMI periprocedural composite end point plus ipsilateral stroke at up to 3 years for long-term evaluation. METHODS: This prospective, multicenter clinical trial enrolled 220 consecutive participants between November 29, 2006, and January 14, 2008, followed by a second cohort of 102 participants between January 14 and June 18, 2008. Enrolled participants had carotid stenosis (symptomatic >50% or asymptomatic >80%). The first 220 subjects underwent distal EPD placement with a new large-diameter filter, and the second cohort of 102 underwent placement of an older EPD that is no longer manufactured. All 322 participants were to be treated with a dedicated carotid stent with a tapered, small, closed-cell design (Xact; Abbott Vascular) and were to be included in the long-term evaluation. Independent neurologic assessment was performed before CAS and at 1 day, 30 days, and annually after CAS. All primary end point events were independently adjudicated by a central committee. RESULTS: The periprocedural composite end point of DSMI (95% confidence interval) in the first 220 participants was 2.3% (0.74%, 5.22%), with a combined death and stroke rate of 1.8% (0.50%, 4.59%) and a rate of death and major stroke of 0.5% (0.01%, 2.51%). As of January 3, 2011, the median follow-up for the entire 322-subject cohort for the long-term evaluation was 2.8 years. Freedom from the periprocedural composite of DSMI plus ipsilateral stroke thereafter was 95.4%, with an annualized ipsilateral stroke rate of 0.4%. CONCLUSIONS: CAS outcomes in patients at high risk for CEA have improved from earlier carotid stent trials. With periprocedural rates of DSMI of 2.3%, death or stroke at 1.8%, and death or major stroke rate of 0.5%, PROTECT has the lowest rate of periprocedural complications among other comparable single-arm CAS trials in patients at high risk for CEA.
PMID: 22236885 [PubMed - as supplied by publisher]
Stent grafting for aneurysmal degeneration of chronic descending thoracic aortic dissections.
J Vasc Surg. 2012 Jan 11;
Authors: Nathan DP, Woo EY, Fairman RM, Wang GJ, Pochettino A, Desai ND, Bavaria JE, Jackson BM
Abstract
OBJECTIVE: The objective of this study was to examine the results of thoracic endovascular aneurysm repair (TEVAR) for chronic descending thoracic aortic (DTA) dissections with aneurysmal degeneration. METHODS: Over 70 months at a single institution, 27 patients underwent TEVAR for aneurysms related to chronic (>6 weeks) DTA dissections. RESULTS: Mean patient age was 67.5 ± 9.6 years; 18 were men. Primary indications for repair were aneurysm size (n = 20), rapid aneurysmal growth (n = 5), saccular aneurysm (n = 1), and rupture (n = 1). Preoperative false lumen status was patent in 18 patients, partially thrombosed in 8 patients, and unknown in the patient whose aneurysm ruptured. The proximal entry tear was covered in all 27 patients. Fourteen patients required coverage of the left subclavian artery, of which 9 patients underwent prophylactic revascularization. On completion angiogram, no patient had antegrade perfusion of the aneurysmal false lumen. There were three procedural complications: 2 patients sustained paraparesis (one resolved and one improved), and 1 patient had an access injury requiring stent graft placement. Thirty-day mortality was 3.7% (1 of 27); the one death was in the patient whose aneurysm ruptured. Of the 26 surviving patients, 23 (88.5%) had thrombosis of the aneurysmal false lumen. Twenty-two patients (84.6%) had stability or decrease in maximal aneurysm diameter on last radiographic follow-up at 18 ± 20 months. Three-year Kaplan-Meier survival was 90.3% ± 6.5% in the 26 patients who survived to hospital discharge, with a mean follow-up of 27.3 ± 22.1 months. In patients with preoperatively partially thrombosed false lumens (n = 8), 3-year survival was 100%. CONCLUSION: TEVAR for aneurysms due to chronic dissections of the DTA can be performed safely and effectively at midterm follow-up according to this single-institution study. Stent graft therapy may be of particular benefit in patients presenting with partially thrombosed false lumens.
PMID: 22244358 [PubMed - as supplied by publisher]
