Difference In Patency Rates Research Articles

Comparison of Cryopreserved Arterial Allografts Versus Heparin-bonded Vascular Grafts in Infragenicular Bypass for Chronic Limb Threatening Ischemia

The purpose of this study was to compare cryopreserved arterial allograft (CAA) to heparin-bonded prosthesis (HBP) in infragenicular bypasses for patients with chronic limb-threatening ischemia (CLTI). This retrospective study took place in 2 university hospitals and included 41 consecutive patients treated for CLTI. In the absence of a suitable saphenous vein, an infragenicular bypass was performed using either CAA (24 cases) or HBP (17 cases). Kaplan-Meyer analysis compared primary and secondary patency and amputation-free survival rates. Binomial logistic regression analyzed risk factors for major amputation and thrombosis. The mean followup was 18.5months (±14.3) in the CAA group, 17.6 (±6.1) in the HBP group. In the CAA group, primary and secondary patency rates at 12months were 52% (±10.6) and 61% (±10.3), compared to 88% (±7.8) and 94% (±5.7) in the HBP group, respectively. The difference in patency rates was not statistically different (P=0.27 and P=0.28, respectively). The statistically significant factors of graft thrombosis were, a stage 4 from the WIfI classification (Wound Ischemia foot Infection) with a 6 times higher risk (P=0.04), and a distal anastomosis on a leg artery with a 9 times higher risk of thrombosis (P=0.03). Amputation-free survival rates at 18months were similar between the groups (CCA: 75% (±9) versus HBP: 94% (±6), P=0.11). Patients classified as WIfI stage 4 had 13 times higher odds to undergo major amputation than patients with WIfI stage 2 or 3 (95% CI, 1.16-160.93; P=0.04). The intervention was longer in the CCA group of 74min (278min±86) compared to the HBP group (203min±69). This difference was statistically significant (95% CI, 17.86-132.98), t(35)=2.671, P=0.01. CCA is not superior to HBP in infragenicular bypasses for CLTI, and may not be worth the extra cost and the longer operative duration.

Evolving strategies for the management of venous thoracic outlet syndrome

ObjectiveTraditional management of venous thoracic outlet syndrome (VTOS) has involved catheter-directed thrombolysis (CDT) followed by transaxillary or paraclavicular (PC) first rib resection. More recently, we have adopted an infraclavicular (IC) approach for first rib resection and five other strategies to treat these patients. We report our evolving experience with the treatment of acute VTOS. MethodsWe reviewed our prospectively maintained database to identify patients treated for VTOS. Our strategy includes CDT with pharmacomechanical thrombectomy, IC first rib resection during the same hospitalization, and subclavian vein angioplasty immediately after rib resection. Postoperatively, a sequential compression device was applied to the affected arm and low-dose heparin given through the ipsilateral venous sheath. Antiplatelet therapy was given for 6 weeks and anticoagulation for 6 months. Our strategy evolved from a PC to an IC approach, given that the added morbidity of the supraclavicular approach to allow excision of the posterior portion of the rib may add no benefit with VTOS compared with arterial or neurogenic thoracic outlet syndrome. ResultsThere were 51 patients who underwent first rib resection for VTOS, 11 (22%) through a PC approach and 40 (78%) through an IC approach. The average age was 36 years (range, 16-63 years), and the majority were female (36 [71%]) and involved the right subclavian vein (36 [71%]). All patients underwent preoperative CDT, 40 (78%) at our hospital and 11 (22%) elsewhere. Fifty patients (98%) underwent subclavian vein angioplasty after rib resection. A bare-metal stent was placed in two (4%) patients for persistent stenosis. Average length of stay was 3.7 (±2.1) days. Average operative time was 2.2 hours (range, 1.5-3.0 hours) when the IC approach was used vs 3.5 hours (range, 2.5-4.5 hours) for the PC approach (P < .0001). Of the entire group, one (2.6%) patient required reoperation for wound hematoma and six (12%) patients underwent repeated endovascular intervention for recurrent vein stenosis during follow-up (average, 38 months; range, 1-240 months). Primary and assisted primary patency rates at 3 years were 78% and 100%, respectively. There were no significant differences in patency rates or complications between the IC and PC approaches. ConclusionsOur transition to an IC approach demonstrated low perioperative morbidity and excellent subclavian vein patency rates with shorter operative times compared with a PC approach. Our practice has evolved to include IC first rib resection followed by concomitant postoperative venous balloon angioplasty.

Drug-Coated Balloon Angioplasty in Hemodialysis Circuits: A Systematic Review and Meta-Analysis

PurposeTo perform a systematic review and meta-analysis assessing patency outcomes following drug-coated balloon angioplasty (DCBA) in hemodialysis circuits. Materials and MethodsMEDLINE and EMBASE systematic searches were performed from inception to November 2018 to identify comparative studies assessing DCBA vs plain old balloon angioplasty (POBA) in hemodialysis circuits. Abstract selection, data extraction, and quality assessment were performed by 2 independent reviewers. Primary outcome was loss of target lesion patency at 3, 6, 12, and 24 months for autogenous arteriovenous fistula (AVF), prosthetic arteriovenous graft (AVG), and hemodialysis-related central venous stenosis. ResultsTwelve studies comprising 908 patients were included. There was a significant improvement in patency among AVF after DCBA vs POBA at 3, 6, 12, and 24 months (odds ratio 0.58 [95% confidence interval, 0.36–0.94]; odds ratio 0.40 [95% confidence interval 0.23–0.70]; odds ratio 0.39 [95% confidence interval, 0.25–0.61]; and odds ratio 0.20 [95% confidence interval, 0.07–0.62]). This benefit persisted on subgroup analysis of randomized controlled trials (RCTs) only. Meta-analysis of results specific to AVG could not be performed, as only 1 RCT was identified that favored DCBA. Hemodialysis-associated central vein stenosis did not demonstrate a significant difference in patency rates between DCBA and POBA on meta-analysis. Twelve-month mortality and same-day complication rates did not differ between arms. ConclusionsSignificant improvement in patency was identified with DCBA in AVF at 3, 6, 12, and 24 months. A single comparative study identified benefit of DCBA use in the AVG group. No significant benefit was identified with DCBA for central stenosis.

Robot-assisted microsurgical vasovasostomy: the learning curve for a pure microsurgeon

Vasovasostomy success rates improved with the application of the operative microscope in 1975. The robotic platform offers potential advantages including: a stable, ergonomic, scalable control system with three-dimensional visualization and magnification, the elimination of physiological tremor, and simultaneous control of three instruments and a camera. A previous publication revealed a fellowship-trained microsurgeon (PKK) could transition to robot-assisted microsurgical vasovasostomy (RAVV) with comparable outcomes. The objective of this current study was to evaluate the learning curve for the purely trained microsurgeon transitioning to RAVV. A retrospective chart review was performed of a microsurgeon’s first 100 RAVVs evaluating the learning curve for patency rates, anastomosis times, operative times, and sperm concentrations at the initial postoperative semen analyses. Cases were stratified into four groups by 25 case intervals. There were no statistically significant differences in patency rates or postoperative sperm concentrations between the groups over time. There were differences in anastomosis times between groups 1 and 2, as well as between groups 2 and 3, and there were differences in operative times between groups 2 and 3. High-percentage patency rates are achievable very early in the transition from pure microsurgical vasovasostomy to RAVV across wide ranges of obstructive intervals. Postoperative mean sperm concentrations in the initial semen analyses after RAVV are consistent over time. For a single microsurgeon not formally trained in robotic microsurgery, 75 RAVV cases were required to optimize and plateau in anastomosis times and 75 cases were required to optimize operative times.

Cerebral revascularization for the management of complex intracranial aneurysms: a single-center experience.

Because simple intracranial aneurysms (IAs) are increasingly treated endovascularly, neurovascular surgery has become focused on complex IAs that may require deconstructive aneurysm therapy with concomitant surgical bypass. The authors describe the decision-making process concerning cerebral revascularization and present outcomes that were achieved in a large case series of complex IAs managed with cerebral revascularization and parent artery occlusion. The authors retrospectively reviewed the medical records, including neuroimaging studies, operative reports, and follow-up clinic notes, of all patients who were treated at the National Brain Aneurysm Center between July 1997 and June 2015 using cerebral revascularization as part of the management of an IA. They recorded the location, rupture status, and size of each IA, as well as neurological outcome using the modified Rankin Scale (mRS), aneurysm and bypass status at follow-up, and morbidity and mortality. The authors identified 126 patients who underwent revascularization surgery for 126 complex, atheromatous, calcified, or previously coiled aneurysms. Ninety-seven lesions (77.0%) were unruptured, and 99 (78.6%) were located in the anterior circulation. Aneurysm size was giant (≥ 25 mm) in 101 patients, large (10-24 mm) in 9, and small (≤ 9 mm) in 16 patients. Eighty-four low-flow bypasses were performed in 83 patients (65.9%). High-flow bypass was performed in 32 patients (25.4%). Eleven patients (8.7%) underwent in situ or intracranial-intracranial bypasses. Major morbidity (mRS score 4 or 5) occurred in 2 (2.4%) low-flow cases and 3 (9.1%) high-flow cases. Mortality occurred in 2 (2.4%) low-flow cases and 2 (6.1%) high-flow cases. At the 12-month follow-up, 83 (98.8%) low-flow and 30 (93.8%) high-flow bypasses were patent. Seventy-five patients (90.4%) undergoing low-flow and 28 (84.8%) high-flow bypasses had an mRS score ≤ 2. There were no statistically significant differences in patency rates or complications between low- and high-flow bypasses. When treating challenging and complex IAs, incorporating revascularization strategies into the surgical repertoire may contribute to achieving favorable outcomes. In our series, low-flow bypass combined with isolated proximal or distal parent artery occlusion was associated with a low rate of ischemic complications while providing good long-term aneurysm control, potentially supporting its wider utilization in this setting. The authors suggest that consideration should be given to managing complex IAs at high-volume centers that offer a multidisciplinary team approach and the full spectrum of surgical and endovascular treatment options to optimize patient outcomes.

AB093. The effect of different strategies of vessel management on vasovasostomy

BackgroundTo study the effect of different strategies of vessel management on vasovasostomy.MethodsFifty 8-week-old male Sprague-Dawley rats were randomly divided into groups A, B, C, D and E. In group A all the vessels were preserved. In group B all vessels were ligated and cut. In group C only arteries were preserved. In all the groups above end to end anastomosis were performed and contralateral testis was removed. In group D only veins were preserved. Group E is the control group with vas deferens intact. All rats’ testicles were measured the size before operations. After 4 weeks, the rats were raised with female rats with 1:1 in the same cage for 2 weeks and the number of pregnant rats were recorded. Then rats were sacrificed, dissected and testicles and vas deferens were collected and detect the patency.ResultsThe patency rate was 90%, 80%, 90%, 80%, 100% and conception rate was 30%, 30%, 20%, 30%, 80% in groups A, B, C, D and E respectively. Preoperative testicular volume was 1.88667±0.11912, 1.176293±0.06971, 1.91651±0.1163, 1.82947±0.12312, 1.80818±0.149 cm3 in groups A, B, C, D and E respectively and 6 weeks postoperative testicular volume was 1.21519±0.19, 1.20181±0.17, 1.27018±0.29, 1.23696±0.21, 1.78842±0.12 cm3. Rate of testicular atrophy was 70%, 50%, 50%, 70%, 0% and rate of postoperative adhesion was 60%, 50%, 50%, 60%, 0% in groups A, B, C, D and E respectively. There was no significant difference in patency rate, conception rate, testicular atrophy and adhesion among the groups (P>0.05) while statistically significant to the control group (P<0.05). Logistic regression analysis showed postoperative adhesion increased the risk testicular atrophy. (OR =60.000000, P<0.05), while testicular atrophy was negatively correlated with pregnancy rate (OR =0.048128, P<0.05).ConclusionsDevascularization does not affect the surgical outcomes of vasovasostomy (VV). Postoperative adhesion can increase the risk of testicular atrophy after vasovasostomy, then consequently affects the rate of pregnancy. Reduction in postoperative adhesion may play a role in vasovasostomy outcomes.

Multifactor analysis of postoperative patency of microsurgical vasoepididymostomy

Objective To analyze the factors which may affect postoperative patency of microsurgical vasoepididymostomy (VE). Methods Ninety-four patients underwent VEs from September 2014 to June 2016 in the Department of Urology, Peking University Third Hospital, with average age of (30.7±4.8)years, and body mass index(BMI) of (25.1±3.0) kg/m2. Semen analyses were performed 1 month, 3 months and 5 to 6 months after the operation. The following semen analyses were performed every 3-6 months thereafter. Patency was defined by finding sperms in twice or more analyses during the follow-up until August 2017. Patients were followed up by face-to-face or telephone interview. Seven factors (age, BMI, bilateral or unilateral anastomosis, anastomosis sites, the adjustment of anastomosis sites, motility and quantity of sperms found in epididymal fluid) were analyzed by Chi-square analysis and multifactor logistic regression analysis. Results Eighty-two patients were followed up (87.2%, 82/94) while 12 patients were lost of follow-up. The mean follow-up time was 19 months. Sperms were found in the ejaculate in 59 patients postoperatively. The overall patency rate was 72.0% (59/82), and natural paternity rate was 32.8% (19/58). Patients ≤28 years old and those >28 years old had patency rates of 89.3% (25/28) and 63.0% (34/54, P=0.012), respectively. Patients with BMI<26.0 kg/m2 and BMI≥26.0 kg/m2 had patency rates of 80.4% (41/51) and 58.1% (18/31, P=0.029), respectively. Patency rate of bilateral surgery was 72.1% (44/61) and of unilateral surgery was 71.4% (44/62, P=0.727). Patency rate of caput anastomosis achieved 75.0% (15/20) and of corpus/caudal anastomosis was 71.0% (44/62, P=0.727). Patency rates of patients with and without adjustment of anastomosis sites were 77.8% (7/9) and 71.2% (52/73, P=0.680), respectively. Patency rates of a lot, a few, motile and seldom-motile sperms in epididymal fluid were 74.3% (55/74) vs. 50.0% (4/8, P=0.146) and 70.0% (28/40) vs. 73.8% (31/42, P=0.701), respectively. Multifactor logistic regression analysis showed that age was well associated with patency rate (OR=4.705, 95%CI 1.181-18.742, P=0.028). Conclusions Age ≤28 years is an independent factor leading to higher patency rates. Patients with lower BMIs and younger could have higher patency rates. Factors of anastomosis sides, anastomosis sites, the adjustment of anastomosis sites, motility and quantity of sperms found in epididymal fluid showed no statistical difference in patency rates. Key words: Infertility, male; Obstructive azoospermia; Microsurgery; Vasoepididymostomy

Drug-Eluting Stent Shows Similar Patency Results as Prosthetic Bypass in Patients with Femoropopliteal Occlusion in a Randomized Trial

Claudication and critical limb threatening ischemia are significant causes of mortality in the elderly. The gold standard of superficial femoral artery (SFA) revascularization is thus far considered to be the femoropopliteal bypass. The aim of this study was to compare mid-term patency between drug-eluting stents (DESs) and prosthetic bypass grafts (BSX). Studies have reported comparable results for both the methods. Forty-six patients with claudication or rest pain due to a 5-25cm SFA occlusion were randomized between DES and BSX groups. The follow-up period was 24months, and the primary outcome measure was overall patency. Secondary outcome measures were primary and primary assisted patency, change in ankle-brachial index (ABI), and amputation-free survival. Forty-one patients were eventually analyzed. Six-month secondary patency was 91% (DES) versus 83% (BSX) (P=0.450). The corresponding numbers at 12 months in the DES and BSX groups were 74% and 80% (P=0.750), respectively. At 24months, the respective numbers were 56% and 71% (P=0.830). There were no statistically significant differences in primary or assisted primary patency at 1, 6, or 12months. There were no demonstrable differences in patency rates or clinical outcomes such as ABI or major amputations between DES and BSX. Although underpowered, the results suggest noninferiority of the DES compared with prosthetic bypass surgery. The trial was preregistered at ClinicalTrials.org (NCT01450722).

Tratamiento endovascular de la isquemia crítica en mujeres

Introduction/objectiveSome distinctive characteristics of peripheral arterial disease in women have recently been identified. The purpose of this study is to analyse differences between men and women with critical limb ischaemia, as regards risk factors, clinical manifestations, and outcomes of endovascular treatment. Material and methodsA retrospective analysis was performed on patients with critical limb ischaemia who underwent endovascular surgery in our centre during 2010-2012. An assessment was made of the risk factors, quality of life (Barthel score), Rutherford grade, time-to-diagnosis, endovascular procedure, pre- and post-interventional ankle brachial index, complications, major amputation rate, patency rates and mortality. Statistical analysis was performed using the SPSS 21.0 statistics package. ResultsThe study included 120 patients (32.5% women), with a mean follow-up of 16.8 months. Univariate analysis showed significant differences in the proportion of smokers (69.1% men vs. 15.4% women), obesity (34.5 vs. 53.8%), Barthel score<35 (12.3 vs. 51.3%), time-to-diagnosis (58.31 vs. 36 days), and age (71.3 vs. 76.9 years). The multivariate analysis showed differences in baseline creatinine levels (1.5 vs. 1.2mg/dl), smoking, obesity and Barthel score<35. Patency rates and survival after endovascular treatment were lower in women, with no statistical significance. ConclusionsWomen with critical limb ischaemia were older, suffer from obesity, were less likely to be smokers, and had less impaired quality of life. There were no differences in patency rates and mortality after endovascular treatment.

Factors Affecting the Results of Superficial Femoral Artery Stenting.

The aim of this study was to assess the durability of superficial femoral artery (SFA) stents and factors that affect stent patency. A retrospective assessment of 214 SFA stent procedures between 2003 and 2012 was conducted from a prospectively compiled database. Patency rates and patient outcomes were compiled from case notes and computerized records. Stent patency was confirmed by either duplex scan or clinical examination (palpable distal pulse). Survival and patency were compared across a range of factors using Kaplan-Meier plots and log-rank tests. Factors found to be significant were further assessed by Cox regression models. Data were analyzed for 214 limbs in 205 patients. Inclusion criteria included those patients who received an SFA stent for treatment of claudication or critical limb ischemia (CLI) with follow-up data. This gave a study group of 151 limbs divided into 76 claudicant and 75 patients with CLI (male-female ratio = 103:48, mean age 71 years, standard deviation 11.7). Seventy-one percent of procedures were elective and 29% were emergency procedures; 53% of procedures were carried out on a day case basis. Median follow-up was 11 months (range 1 day-89 months). Patency was significantly worse for patients with CLI (P = .009), with a 1- and 3-year patency of 63% and 34% compared to 79% and 60% in patients with claudication. Significant factors associated with patency included oral therapy controlled diabetes (P = .003), lesions located in either the mid-SFA (P = .029) or the mid-popliteal (P = .013), and periprocedural complications (P = .005). There was no significant difference in patency rates between insulin-dependent and nondiabetic patients (hazard ratio: 1.0, 95% confidence interval: 0.4-5.6, P = .983). The overall amputation rate for the total study group was 5%. Patients with 1- and 3-year survival were 98% and 96% in the claudication group and 74% and 51%, respectively, in the CLI group. SFA stents have superior outcomes in claudicants. Patency is related to severity of disease, diabetes, and location of disease.

Effect of Intra Operative Intravenous Injection of Heparin on Patency Rate of Radio Cephalic Autogenous Arteriovenous-Fistula in Chronic Renal Failure Patients

Background: Currently, there is no standard for the use of systemic heparin during creation of Arteriovenous (AV) fistula to decrease the incidence of postoperative thrombotic complications. Objectives: The goal of this study was to evaluate the effects of intra-operative IV heparin on patency rate and postoperative bleeding complications in patients undergoing surgery for AV fistula. Patients and Methods: A prospective, randomized controlled study was performed on 50 patients undergoing AV fistula creation, who were randomly divided in two groups. The control group received no systemic heparin and the heparin group received 5,000 units of intravenous heparin before clamping of theartery. Results: There was a significant difference in patency rate between the heparin and control groups (96% vs. 72%, P = 0.021), and there were no significant differences in operative time (P = 0.55). Perioperative bleeding was not significantly different between the two groups. Conclusions: The results suggest that intra operative administration of heparin has statistically significant effects on patency rates yet not on postoperative bleeding complications. Larger trials with longer follow-up durations and assessment of maturation rates are needed to determine this effect on fistula outcome.

Should patients with infrainguinal arterial bypasses using autologous vein conduit undergo follow-up surveillance with duplex ultrasound?

This best evidence topic was investigated according to a structured format. The question asked was: should duplex ultrasound (DUS) scanning be a routine component of surveillance following infrainguinal arterial bypass using vein conduit? We performed a systematic literature search and identified 4 studies (3 randomised controlled trials and 1 meta-analysis) that provided the best evidence.The highest quality study was a multi-centre randomised controlled trial (n = 594). At 18 months following surgery, it found no difference in patency rates, amputations, vascular mortality or mortality. However it achieved just over half of anticipated recruitment and thus was underpowered. The remaining two randomised controlled trials had smaller sample sizes and methodological weaknesses and found conflicting results. Lundell et al. (n = 106) found improved primary assisted and secondary patency rates and fewer graft occlusions with a routine DUS policy. Ihlberg et al. (n = 152) found no difference in primary assisted patency or amputations although secondary patency was improved. A meta-analysis of mostly observational data (n = 6649) found fewer occlusions with routine DUS surveillance and no effect on amputations or mortality.Results are conflicting. The strongest evidence comes from the single high quality multi-centre trial. It appears as though routine DUS surveillance does not yield benefits in patient important outcomes. Further studies are needed.

Intravascular stenting in microvascular anastomoses.

The effect of intravascular stenting (IVaS) on microvascular anastomoses has given adverse results. For experienced microsurgeons the benefit of IVaS is doubtful. We have investigated the potential benefit of the IVaS technique for two groups of inexperienced microsurgeons with different surgical levels of experience (medical students and young residents). Experienced microsurgeons acted as a control group. In an experimental crossover study, 139 microsurgical anastomoses were performed on the femoral artery in 70 rats by 10 surgeons. On one side of the rat, the IVaS technique was used. A small piece of 5-0 nylon monofilament was placed in the vessel lumen, acting as a temporary stent during microvascular anastomosis. A conventional technique without the stent was performed on the other side. Patency rates of the vessels in each group were compared as well as the time spent on the anastomosis. No significant difference in patency rates was seen between the stenting and conventional technique in all three groups. The experienced microsurgeons had 100% patency rate with both techniques. The medical students had 20/28 in the IVaS and 19/28 conventional group and the patency rates for the residents were 23/27 using IVaS and 23/28 using the conventional technique. The residents were faster using the IVaS whereas the students and experienced microsurgeons were faster without the stent. The IVaS technique did not seem to benefit either the inexperienced or experienced microsurgeons regardless of their clinical experience. The study also shows that some surgical experience seems to be an advantage in performing microsurgery.

“No-Touch” versus “Endo” Vein Harvest: Early Patency on Symptom-Directed Catheterization and Harvest Site Complications

"No-touch" (NT) saphenous vein harvesting preserves the adventitial vasa vasorum, prevents medial ischemia, and is associated with an improved short-term and long-term vein graft patency. It may also be associated with a higher rate of harvest site complications. Endovascular vein harvesting (endo-vein) has a low rate of harvest site complications but also a tendency toward a lower patency rate. During a 2-year period (2011-2012), we compared the vein graft patency at symptom-directed cardiac catheterization as well as wound complication rates in 210 patients who received either NT (87 patients) or endo-vein (123 patients). The recatheterization rate for the two groups was similar: 9 (10.3%) of 87 of the NT patients versus 11 (9.0%) of 123 of the endo-vein patients. There was a significant difference in vein graft patency between the groups: 15 (94%) of 16 NT vein grafts were patent versus 6 (27%) of 22 of endo-veins (P < 0.02). The endo-vein graft patency during this 2-year period was similar to the total endo-vein patency (37%) during a 4-year period. A comparison between a more experienced and a less experienced harvester revealed no difference in patency rate. Harvest site complications were significantly higher with the NT harvest: 18% of the NT patients requiring vacuum-assisted wound closure or intravenous antibiotics versus 2% of the endo-vein patients (P < 0.0001). The application of platelet-rich plasma did not significantly lower wound complication rates (P = 0.27). These results suggest that NT vein harvesting may be associated with improved graft patency, but methods should be developed to lower wound complication rates.

Endovascular treatment of external iliac artery occlusive disease: midterm results.

To report midterm outcomes for endovascular treatment of external iliac artery (EIA) occlusive disease and assess possible factors affecting patency. A retrospective analysis was conducted of 99 consecutive patients (91 men; mean age 67.3 years) with claudication (n=70) or critical limb ischemia (n=29) owing to occlusive EIA disease treated at our center from January 2005 to June 2012. The majority of lesions (79/108) were TASC A/B. Lesions were a mean 42.2 mm long (range 10-125); 43/108 affected the distal third of the EIA. Balloon angioplasty alone was performed in 7 limbs, while the remaining 101 lesions were stented (65 self-expanding, 24 balloon-expandable, and 12 covered). Clinical and hemodynamic follow-up was performed at 1, 3, 6, and 12 months after therapy and yearly thereafter. The factors examined were procedure characteristics and patency rates. Over a median follow-up of 27.5 months (range 1-89), there were 2 (1.9%) early occlusions followed by a successful reintervention, 4 late occlusions, and 5 hemodynamic failures followed by 7 reinterventions. These events led to primary and secondary patency rates at 30 months of 89.7% and 94.1%, respectively. No differences in patency rates were detected according to age, clinical state, or comorbidity. Use of covered stents (p=0.006) was the only variable associated with lower primary patency rates. Endovascular therapy to treat TASC A/B lesions of the EIA yielded good short and midterm patency and low early morbidity and mortality. Lesions involving the distal third of the EIA treated by simple angioplasty ± stenting fared worse. No clinical factors could be correlated with patency.

Short-Term Clinical Experience with a Dedicated Venous Stent.

Deep venous stenting has become the primary treatment option for chronic venous obstructive disease, both for iliac vein compression syndromes and post-thrombotic venous lesions, during the last decade. Until recently only arterial-designed materials were available; no dedicated venous stents were available. These venous stents are characterized by increased length, diameter, flexibility, and radial force. Recently, three such stents have become available. We report our early experience with one such devices; the Sinus Venous stent (OptiMed, Ettlingen, Germany). Between March 2012 and July 2013, 48 patients were treated with the Sinus Venous stent. These included six cases of stenting after thrombolysis for acute DVT, 11 cases of stenting for isolated iliac vein compression syndrome (May-Thurner), and 31 cases of stenting for chronic venous obstruction in post-thrombotic syndrome patients. Diagnosis of relevant obstruction was made by use of clinical evaluation combined with duplex ultrasound, magnetic resonance venography, and periprocedural venography. Patency control during follow-up was assessed with duplex ultrasound. Cumulative patency rate at 3 months was 83%, 84%, and 97 % for primary, primary assisted, and secondary patency, respectively. Differences in patency rate between the subgroups of acute thrombotic, post-thrombotic, and nonthrombotic exist, with the latter fairing significantly better. All reocclusions were treated by ancillary treatment modalities, including catheter directed thrombolysis, rePTA, and restenting. Morbidity was low, no clinically relevant pulmonary embolisms occurred, and mortality was nil. Short-term clinical results using the Sinus Venous stent are excellent, with acceptable morbidity rates, and no mortality. As already reported in other venous stenting series, thrombotic lesions have lower patency rates compared with nonthrombotic lesions.

E-Comment: Conducting meta-analyses of off-pump versus on-pump coronary artery bypass surgery: where we stand

We read with great interest the paper by Tagaki et al. in which the authors concluded that off-pump coronary artery bypass grafting (CABG) may increase repeat revascularization by 38% over on-pump CABG. We would like to mention some aimportant issues about this meta-analysis and about what we expect from a meta-analysis. Were the inclusion criteria similar in the studies of this meta-analysis? Were the participants at the same or higher surgical risk, as evidenced by: 1) the selection criteria and 2) the baseline characteristics (e.g. age of patients, ejection fraction and elective or emergency surgery)? Differences in the design and patient population exist in the studies. Did the patients have a similar distribution of coronary artery disease in both arms in the studies? What about the grafts that were used? Did all surgeons use similar grafts (left mammary artery, right mammary artery, radial artery, composite arterial grafts or vein grafts) and did they use the same graft for the same target lesion? Was the number of anastomoses planned in the two groups similar? Did the patients receive the same number of grafts during off-pump and on-pump? Fewer anastomoses were performed to the lateral territory of the heart during off-pump so there is incomplete revascularization. Finally, fewer grafts were performed in the off-pump group in most trials. The technical details were left to the discretion of the operating surgeon so there is a great variability. Doing coronary anastomoses on the beating heart is more challenging and may result in poorer quality and in an increased risk of early occlusion. Is expressing count data (number of grafts) ideal as a mean value owing to the necessary distributional assumption? Was the surgical experience of surgeons who participated in the studies at the same level? Another important issue that is relevant with graft patency is the anticoagulation agents that were used after on-pump and off-pump. Did the patients receive the same anticoagulation agents? Lower anticoagulation might explain the difference in patency rates in the off-pump group. There were no predefined criteria for indication of repeat revascularization which is very important. We would also like to define our expectations from a meta-analysis. The detection of a true treatment effect is useful for clinical use but the decision what to do requires the magnitude of the treatment effect. An advantage of the meta-analysis is the ability to reach a more accurate treatment effect with reduced uncertainty (tight confidence intervals) [2]. We can see that the confidence intervals in some trials in this meta-analysis are not tight so there is uncertainty. Meta-analysts should focus on a group of biases that are clustered under the term 'significance-chasing biases'; these include publication bias, selective outcome reporting bias, selective analysis reporting bias and fabrication bias [3]. A number of tests have been developed to detect and exclude publication bias, but these tests may be affected by any type of significance-chasing bias and may also be affected by the diversity across the study-specific effects [4]. A careful meta-analysis protocol is essential for a more accurate and focused analysis ('The PRISMA statement' [5]). Off-pump is a technically challenging surgical procedure and remains a very important tool for specific groups of patients. Conflict of interest: none declared

Should we use saphenous vein graft instead of synthetic graft for creation of secondary arteriovenous fistula in hemodialysis dependent end stage renal failure patients?

Background: Patient groups with secondary arteriovenous fistula (AVF) management with saphenous vein (SV) graft and polytetrafluoroethylene (PTFE) graft for hemodialysis (HD) were reviewed in terms of patency and complication rate. Methods: Forty HD access procedures were performed in 40 consecutive patients between January 2006 and January 2010. All access procedures were planned on the basis of preoperative duplex ultrasonography (USG) scans of arm and forearm veins. Functional patency was defined as ability to cannulate for HD successfully for the patient. Primary and secondary cumulative functional patency of SV and PTFE grafts were determined with Kaplan Meier test; differences in patency rates were analyzed with Log Rank test and differences in revision rates including thrombolysis, thrombectomies and operative revisions were analyzed with the Z test and the Fisher's exact t-test. Results: Mean follow-up was 48 months (range 43-54 months). Risk factors were similar between the two groups. Saphenous vein graft had better patency rates. The HD access complications were higher in SV graft group, while infection and thrombosis were higher in PTFE group. Conclusion: Our data strongly support the necessity that SV graft should be considered initially, compared to PTFE graft, for the patient who is a candidate for an upper arm secondary AVF creation based on anatomical criteria.

Early Cannulation Grafts in Straight Axillo‐Axillary Angioaccesses Avoid Central Catheter Insertions

The need for early cannulation grafts exists to prevent use of central venous catheters. We report our experience in patients who had a straight axillo-axillary angioaccess. All patients who have undergone an early cannulation axillo-axillary angioaccess between 2008 and 2010 were reviewed. Fifteen patients had 16 procedures. Of these, eight were women and their mean age was 56. All patients had exhausted access options bilaterally. All had previous catheter insertions with either sepsis or jugular veins thrombosis. They all had an axillary artery to axillary vein angioaccess using an early cannulation graft. Flixene(®) (Atrium Medical, Hudson, NH, USA) was used in 10 cases, whereas Rapidax(®) (Vascutek Ltd., Renfrewshire, UK) in 6. In 12 cases, grafts were cannulated after 12 hours, in 4 after 24 hours (12 hours-8 days, mean 1.8 days). For Flixene(®) , mean delay to cannulation was 1.1 days, whereas 2.71 for Rapidax(®) (p < 0.05). Primary patency rates were 92.9% and 65.7% at 6 weeks and 1 year, respectively. Secondary patency rates were 92.9% and 83.5%. There was no significant difference in patency rates between grafts. Early cannulation grafts in a complex position are safe and efficient considering their patency and complication rates. It avoids using central venous catheters.

Impact of Race on Infrainguinal Angioplasty and Stenting

Over the last decade, catheter-based interventions on lower extremity arteries have been used with increasing frequency. However, the effect of racial background on the outcome of lower extremity endovascular interventions for peripheral arterial disease is unknown. The purpose of this study was to determine the effect of patients' race on the durability of angioplasty and stenting performed on the superficial femoral and popliteal arteries. The records of all patients undergoing percutaneous intervention on the lower extremity arteries during a 14-year period were reviewed. During a 44-month period (2003-2007), all patients underwent primary stenting as part of a prospective study protocol. Indication for intervention, TransAtlantic InterSociety Consensus II classification, runoff anatomy, site of intervention, and the placement of stents were noted. Results were analyzed by race. Kaplan-Meier life survival curves were plotted and differences between groups tested by log-rank method. Cox proportional hazards regression model was used to perform the multivariate analysis. Between 1994 and 2007, a total of 374 percutaneous interventions were performed on the superficial femoral and popliteal arteries in 280 patients. Of these, 182 procedures were angioplasties and 192 included both angioplasty and stenting. The study group consisted of 60% Caucasians, 23% Hispanics, 12% African Americans, and 5% Asians. No difference in primary patency rates was noted between individuals belonging to different races. However, in those undergoing angioplasty alone, Caucasians had the highest rate of failure, followed by Hispanics, African Americans, and then Asians (p < 0.002). No difference in patency rates between races was seen in patients undergoing angioplasty with stenting. For the entire group, dyslipidemia, TransAtlantic InterSociety Consensus II C and D lesions, and angioplasty without stenting negatively affected primary patency. Race does not appear to influence the durability of catheter-based procedures performed on the superficial femoral and popliteal arteries. However, in patients who underwent angioplasty alone, it was noted that Caucasians had the highest rates of failure and Asians the lowest. However, this difference was no longer apparent when stents were used.