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Plant defense responses to pathogens are induced after direct or indirect perception of effector proteins or their activity on host proteins. In fungal-plant interactions, relatively little is known about whether, in addition to avirulence effectors and immune receptors, other proteins contribute to specific recognition. The nucleotide-binding leucine-rich repeat (NLR) immune receptor Pm2a in wheat recognizes the fungal powdery mildew effector AvrPm2. We found that the predicted wheat zinc finger TaZF interacts with both the fungal avirulence protein AvrPm2 and the wheat NLR Pm2a. We further demonstrated that the virulent AvrPm2-H2 variant does not interact with TaZF. TaZF silencing in wheat resulted in a reduction but not a loss of Pm2a-mediated powdery mildew resistance. Interaction studies showed that the leucine-rich repeat domain of Pm2a is the mediator of the interaction with TaZF. TaZF recruits both Pm2a and AvrPm2 from the cytosol to the nucleus, resulting in nuclear localization of Pm2a, TaZF, and AvrPm2 in wheat. We propose that TaZF acts as a facilitator of Pm2a-dependent AvrPm2 effector recognition. Our findings highlight the importance of identifying effector host targets for characterization of NLR-mediated effector recognition., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Durable disease resistance genes such as the wheat gene Lr34 are valuable sources of resistance for agricultural breeding programs. Lr34 encodes an ATP-binding cassette transporter protein involved in the transport of the phytohormone abscisic acid. Lr34 from wheat is functionally transferable to barley, maize, rice and sorghum. A pleiotropic effect of Lr34 induces the development of a senescence-like phenotype, referred to as leaf tip necrosis. We used Lr34-expressing wheat and transgenic barley plants to elucidate the role of abscisic acid in the development of leaf tip necrosis. Leaf tips in Lr34-expressing wheat and barley showed an accumulation of abscisic acid. No increase of Lr34 expression was detected in the leaf tip. Instead, the development of ectopic, Lr34-induced leaf tip necrosis after removing the leaf tip suggests an increased flux of abscisic acid towards the tip, where it accumulates and mediates the development of leaf tip necrosis. This redistribution of abscisic acid was also observed in adult transgenic barley plants with a high Lr34 expression level growing in the field and coincided with leaf tip necrosis as well as complete field resistance against Puccinia hordei and Blumeria graminis f. sp. hordei. In a barley transgenic line with a lower Lr34 expression level, a quantitative resistance against Puccinia hordei was still observed, but without a significant redistribution of abscisic acid or apparent leaf tip necrosis. Thus, our results imply that fine-tuning the Lr34 expression level is essential to balance disease resistance versus leaf tip necrosis to deploy transgenic Lr34 in breeding programs., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The wheat Lr34res allele, coding for an ATP-binding cassette transporter, confers durable resistance against multiple fungal pathogens. The Lr34sus allele, differing from Lr34res by two critical nucleotide polymorphisms, is found in susceptible wheat cultivars. Lr34res is functionally transferrable as a transgene into all major cereals, including rice, barley, maize, and sorghum. Here, we used transcriptomics, physiology, genetics, and in vitro and in vivo transport assays to study the molecular function of Lr34. We report that Lr34res results in a constitutive induction of transcripts reminiscent of an abscisic acid (ABA)-regulated response in transgenic rice. Lr34-expressing rice was altered in biological processes that are controlled by this phytohormone, including dehydration tolerance, transpiration and seedling growth. In planta seedling and in vitro yeast accumulation assays revealed that both LR34res and LR34sus act as ABA transporters. However, whereas the LR34res protein was detected in planta the LR34sus version was not, suggesting a post-transcriptional regulatory mechanism. Our results identify ABA as a substrate of the LR34 ABC transporter. We conclude that LR34res-mediated ABA redistribution has a major effect on the transcriptional response and physiology of Lr34res-expressing plants and that ABA is a candidate molecule that contributes to Lr34res-mediated disease resistance., (© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust.)

Background: To report our preliminary experience with endovascular revascularization of patients with acute mesenteric ischemia (AMI), using thrombectomy devices., Methods: It is a retrospective analysis of patients admitted to our hospital due to AMI and who were subjected to concomitant or exclusive endovascular treatment, from January 2011 to January 2016. Patients were admitted at the emergency department, underwent imaging investigation, and were referred to the endovascular specialist. Endovascular treatment was performed through left brachial artery access and selective catheterization and thrombectomy with a 6F Rotarex Debulking Device (Straub Medical, Wangs, Switzerland). Laparotomy was performed based on clinical and radiologic sings and at the discretion of the surgeon. Demographic, clinical/periprocedural, postoperative, complication, and adjunct intervention data were reviewed. Technical success was defined as recanalization of the Riolan's arcade on angiographic control., Results: Twenty patients (mean age: 69.8 ± 11.3 years) underwent endovascular revascularization for AMI using thrombectomy devices, during the period of the study. Abdominal pain was the most common complain on admission (65%), with ileus (35%), sepsis (25%), and myocardial infarction as the main clinical referral presentation at admission. Fifteen patients (75%) had suggestive computer tomography (CT) signs of AMI on admission. Endovascular revascularization was successfully performed in all patients through the left brachial artery with a mean procedural time of 28 ± 17 min. Superior mesenteric artery (SMA) was the main vessel involved in 75% on a solely basis. The majority of the SMA occlusions were in the periosteal (30%) and proximal to middle colic artery offspring (35%). Primary use of thrombectomy devices was performed in all patients, associated with balloon angioplasty (7/20; 50%), stent deployment (5/20; 25%), intraoperative selective thrombolysis (4/20; 20%) and catheter-assisted aspiration in 10% (2/20) of patients. Average time between admission and computed tomography angiography was 1.5 ± 0.5 hr, between admission and angiographic procedure was 2.5 ± 1 hr, and between admission and surgery was 9 ± 5 hr. Following recanalization, 14 patients (70%) underwent open surgery. Laparotomy with intestinal resection (enterectomy, colectomy) and transit deviation was the most common procedure. Complications directly related to the endovascular procedure occurred in 2 patients, represented by self-limited small perforations. Overall 30-day mortality was 40% (n = 8). During the period of this study, no patient died as a result of complications related to the use of rotational thrombectomy., Conclusions: Endovascular treatment of the AMI with the use of thrombectomy devices proved to be technically feasible and reasonably fast procedure. Early diagnosis and adequate treatment remains the cornerstone of the treatment. Early surgical evaluation and close integration between surgical and endovascular specialists are crucial to faster treatment and consequently lower extensive surgical resections and mortality. Further studies are necessary on this field to confirm these findings., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction: Data regarding the effectiveness and safety of percutaneous mechanical thrombectomy (PMT) in contemporary routine care are scarce., Materials and Methods: Consecutive patients undergoing PMT of native lower limb acutely/subacutely occluded arteries were included., Results: In all, 525 consecutive patients were available for analysis with a mean age of 66.7 ± 10.7 years. Almost two-third (n = 324; 61.7%) were men with acutely (n = 211; 40.2%) or subacutely (n = 314; 59.8%) occluded lesions presenting mostly in Rutherford-Becker category (RBC): 3 (30.3%) and 4 (47.6%). Mean lesion length was 159 mm (range 22-279 mm), with moderate and severe calcification in 119 (23.3%) lesions. PMT was performed solely in 161(27.2%), PMT + balloon angioplasty in 232 (39.1%), provisional stenting in 169 (28.4%), and thrombolysis in 77 (13.9%) interventions. Procedural technical success rate was 97.7%, with improvement in RBC persisting in 74.1% of patients after 12 ± 2.4 months mean time follow-up. Overall 30 days major adverse events (MAEs) was 6.9% with a mortality rate of 1.1%. No death was directly related to the device. After 12 months, a promising overall target lesion revascularization (TLR; 10.1%), non-TLR (6.6%), and major amputation rates (2.3%) were found. One-year mortality was 8%., Conclusion: Treatment with PMT resulted in clinic and hemodynamic improvement in the majority of patients, thereby reducing the need for thrombolysis in a significant proportion of patients. Prospective studies in this issue are recommended.

Purpose: To examine patient outcomes following the use of the Lutonix drug-coated balloon (DCB) in patients undergoing endovascular intervention in below-the-knee (BTK) arteries., Methods: A retrospective chart review identified 248 patients who were treated for symptomatic peripheral artery disease with the Lutonix DCB between May 2013 and October 2014. Forty patients were lost to follow-up, leaving 208 patients (mean age 74.1±9.7 years; 138 men) with evaluable data for outcome analysis. The patient cohort suffered from either severe claudication (38.6%) or critical limb ischemia (CLI; 61.4%) in 220 limbs. Almost two-thirds (140, 63.6%) of the 220 target lesions were total occlusions, and 37 (17.8%) of all patients had occlusion of all 3 BTK vessels before intervention., Results: Over a median 9-month follow-up, target lesion revascularization occurred in 15.9% of patients with an average time to first reintervention of 8 months. In total, 39 amputations were performed in 31 limbs. However, 17 of these amputations were preplanned minor amputations below the ankle; only 9 (4.1%) major amputations occurred corresponding to 6.6% of the CLI cohort. Freedom from the composite of death or major amputation was estimated as 92% and 85% at 6 and 12 months, respectively, by Kaplan-Meier analysis. In the full cohort, improvement of at least 1 Rutherford category was seen in 130 (59.1%) limbs after 1 year or at the last follow-up, with 104 (80.0%) of those limbs showing an improvement of ≥2 categories., Conclusion: From this single-center experience, the Lutonix DCB shows therapeutic promise in a disease state where new treatment options are needed., (© The Author(s) 2016.)

Rationale: We investigated the applicability of tree-ring whole-wood material for δ(18)O and δ(13)C analysis in comparison with the more time- and resource-intensive use of cellulose, by considering possible variability between (i) five different tree species (Fagus sylvatica, Quercus robur, Picea abies, Abies alba, Pseudotsuga menziesii), (ii) two sites that differ in soil moisture, and (iii) climate conditions within a 10-year period., Methods: Stem cores of 30 individual trees (n = 3 trees per each species and site) were sampled from two sites in south Germany (Bavaria), and tree rings within sapwood of the years 2001-2010 were separated. The δ(18)O and δ(13)C values from homogenized tree-ring whole wood and from extracted cellulose were measured by mass spectrometry. Species-specific offsets in isotope values were analyzed and the responses in isotopic signature to climate variability including a single drought event were compared between whole-wood and cellulose., Results: A constant offset in δ(18)O values of ca 5‰ between wood and cellulose was observed for most species independent of site conditions, with a significant difference between beech and Douglas-fir, while inter-annual variability was only observed in oak. The offset in δ(13)C values ranged between 1.45 and 1.84‰ across species, sites and years. Both materials generally showed similar strength in responses to temperature, precipitation and soil water availability, particularly for conifers. Resistance to severe drought stress--partly more strongly reflected in the δ(13)C values of cellulose--was lower for conifers than for the deciduous species., Conclusions: Wood material from the sapwood of the studied tree species is as useful as cellulose for studying environmental effects on tree-ring δ(18)O and δ(13)C values at a short-term scale as considered in most ecophysiological studies. The more variable response of oak may require further investigations., (Copyright © 2015 John Wiley & Sons, Ltd.)

Aims: To examine the efficacy and durability of an interwoven self-expanding nitinol stent in the treatment of complex femoropopliteal artery lesions in unselected patients., Methods and Results: Five hundred and twenty-seven limbs in 470 patients with femoropopliteal arterial disease were treated with SUPERA stents. Follow-up data were prospectively collected in a single-centre registry and were available for 439 patients (492 limbs). The patients were followed by Doppler ultrasound, stent roentgenograms, estimation of Rutherford-Becker class (RBC) and ankle-brachial index (ABI). Total occlusions were present in 277 limbs (52.6%) and 52.4% had either moderate or severe calcification. The mean lesion length was 126.4 mm. The primary patency (PP) rates were 83.3% after 12 months and 72.8% at two years. The secondary patency rates were 98.1% after 12 months and 92.0% at two years. Patency rates did not differ between superficial femoral artery (SFA) and popliteal lesions. Between baseline and a mean of 21 months of follow-up, mean ABI increased from 0.53 to 0.91, and mean RBC decreased from 3.0 to 1.9 (p<0.001 for both comparisons). Radiographs performed on 229 patients at a mean of 16.6 months confirmed the absence of stent fractures in all patients., Conclusions: Over a two-year surveillance period, the patency rate and fracture resistance of SUPERA stents implanted for complex femoropopliteal artery disease were high.

Objectives: To report on the efficacy of drug eluting stents (DES) in below the knee lesions involving arterial bifurcations after failed angioplasty., Background: DES have become a mainstay in the treatment of below the knee lesions. However, little is known about the efficacy of DES in infrapopliteal lesions involving the arterial bifurcations. This is the first report on the endovascular treatment of below-the knee bifurcations., Methods: 11 patients with critical lower limb ischemia and complex infrapopliteal atherosclerotic disease underwent provisional DES placement in infrapopliteal bifurcation lesions. Clinical and angiographic follow-up data were prospectively collected in all patients., Results: Technical success was achieved in all cases. After 6 months, the two vessel primary patency (2VPP) rate was 54.5% and the 1VPP rate was 81.8%. Between baseline and the follow-up, mean ankle-brachial index increased from 0.31 ± 0.10 to 0.68 ± 0.16, and mean Rutherford-Becker class decreased from 4.73 ± 0.20 to 3.00 ± 1.41 (P < 0.001 for both comparisons)., Conclusions: Bifurcation stenting techniques, that are described for the coronary arteries can be also performed in the infrapopliteal arteries. However, early reocclusion was frequent in this case series, when stenting was performed in a bail-out setting. If balloon angioplasty alone leads to no sufficient results in bifurcation lesions, a single stent strategy could also be considered., (Copyright © 2013 Wiley Periodicals, Inc.)

Aim: The aim of this study was to collect procedural and clinical data assessing safety and performance of the GORE® TIGRIS® Vascular Stent, a novel dual component stent, made of a nitinol wire frame combined with a fluoropolymer-interconnecting structure., Methods: This retrospective analysis included 32 consecutive patients (20 men, mean age 72.8 years) with 40 atherosclerotic femoropopliteal lesions (occlusions in 5%) who underwent angioplasty and implantation of a GORE® TIGRIS® Vascular Stent. The patients were scheduled for follow-up at 3, 6 and 12 months after stent implantation for Duplex ultrasound and assessment of Rutherford Becker class (RBC) and Ankle-Brachial Index (ABI) RESULTS: The mean implanted stent length was 62.3 mm (range 30-100 mm). Procedural success (residual stenosis <30%) was achieved in 100% of the lesions. At 6 months 2 restenosis in 2 patients were observed, resulting in a cumulative primary patency rate (±standard error) of 91.7±8.0%. Between baseline and 6 months the ABI increased from 0.65±0.18 to 0.96±0.12 (P<0.0001) and the median of RBC increased from 3 to 1.5 (P<0.0005). No stent thrombosis was found., Conclusion: In this retrospective collection of patients all lesions could be successfully treated with this novel hybrid TIGRIS stent. These preliminary results show promising primary patency rates at 6 months. In addition, significant improvements were observed in symptom classification and hemodynamics.

Aims: Carotid artery stenting (CAS) has become an alternative to carotid endarterectomy in the treatment of carotid artery disease. The use of an embolic protection device (EPD) can reduce the frequency of embolic events during CAS. Difficult vascular anatomy may complicate current generation EPD placement. This problem is addressed by a new EPD, the GARDEX System. The aim of this study was to assess the safety and performance of the GARDEX EPD during CAS., Methods and Results: Thirty-eight patients underwent CAS with the GARDEX EPD in two medical centres. All patients were prospectively followed up for 30 days. Device performance and procedural details were collected and analysed prospectively. Vessel anatomy and lesion morphology were evaluated and stratified into a scoring system for anatomic difficulty. More than a third of the patients were considered to have difficult vascular anatomy for CAS. All enrolled patients were successfully treated. There was one (2.6%) minor periprocedural stroke and there were two (5.3%) periprocedural TIAs which resolved within 24 hours. No additional complications were noted during the 30-day follow-up period., Conclusions: In this first experience, CAS under cerebral protection with the GARDEX EPD was safe and feasible. Our data suggest that the use of the GARDEX EPD is simple and shows high success rates even in challenging anatomies. The role of this new device in CAS needs to be further confirmed in a larger patient population.

Objectives: We examined the efficacy and durability of a new interwoven self-expanding nitinol stent system in the treatment of complex popliteal artery lesions in unselected patients., Background: The optimal endovascular treatment strategy for atherosclerotic popliteal artery disease is not known., Methods: We retrospectively analyzed the data gathered in 101 consecutive patients presenting with atherosclerotic, popliteal arterial disease, who underwent implantation of 125 stents. The patients were followed for 12 months by Doppler ultrasound examinations, stent roentgenograms, and estimation of Rutherford-Becker class (RBC) and ankle-brachial index (ABI)., Results: The mean age of the patients was 73.1 years, and 52.5% were men. Total occlusions were present in 48 patients (47.5%). The mean stent length was 84.3 ± 45.1 mm (range 40 to 240 mm). A <30% residual stenosis was achieved in 98.0% of procedures. The 6- and 12-month primary patency rates were 94.6 ± 2.3% and 87.7 ± 3.7%, respectively, and the secondary patency rates 97.9 ± 1.5% and 96.5 ± 2.0%, respectively. Between baseline and 12 months of follow-up, mean ABI increased from 0.58 ± 0.15 to 0.97 ± 0.18, and mean RBC decreased from 3.1 ± 0.9 to 1.4 ± 0.8 (p < 0.001 for both comparisons). Radiographs performed on 51 patients, at a mean of 15.2 months, confirmed the absence of stent fractures in 100% of examinations., Conclusions: Over a 12-month observation period, the patency rate and durability of SUPERA stents implanted for severe popliteal artery disease were high., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: This study was conducted to identify patient-related variables that are associated with a higher rate of neurological adverse events during carotid artery stenting (CAS)., Background: CAS is considered as an alternative treatment for patients with carotid artery stenosis. Despite technical advancements and increase of operator experience, periprocedural neurologic complications cannot completely be prevented. Case selection based on anatomical criteria and other patient characteristics could improve the outcome after CAS., Methods: Between 2006 and 2009, 833 CAS procedures were performed in 751 consecutive patients under cerebral protection. The influence of patient characteristics, procedural details, and the anatomy of the supraaortic vessels on the incidence of major in-hospital adverse events was assessed., Results: Successful CAS was performed in 99.2% of the procedures. The in-hospital death and stroke rate was 2.0% (1 major stroke, 10 minor strokes, and 7 deaths). Octogenarians had a fourfold higher death and stroke rate than patients younger than 80 years old. There was an increased risk of stroke and death in patients with critical aortic stenosis. Presence of a bovine arch, tortous common carotid artery (CCA) and angulated distal internal carotid artery were associated with a higher risk of stroke and transient ischemic attack. A recently developed scoring system for anatomic suitability correlates well with the periprocedural neurological outcome in this case series., Conclusions: Anatomical conditions and octogenarian age were associated with an increased rate of neurologic adverse events during CAS. Our findings support a newly proposed scoring system for anatomic suitability to identify patients at high risk for CAS., (Copyright © 2012 Wiley Periodicals, Inc.)

Purpose: To evaluate the efficacy and safety of endovascular brachytherapy with liquid beta-emitting rhenium-188 (Re-188) in patients with long-segment in-stent stenosis in the femoropopliteal segment., Methods: From July 2009 to April 2011, 90 consecutive patients (59 men; mean age 68.3±10.3 years, range 43-86) with symptomatic in-stent stenosis/occlusion (24.6-cm mean lesion length) of the femoropopliteal segment underwent angioplasty and subsequent endovascular brachytherapy. The liquid beta-emitting Re-188 was applied to the target lesion within an angioplasty balloon using a dose of 13 Gy at a depth of 2 mm into the vessel wall. Clinical and angiographic follow-up data were collected up to 2 years. The main study endpoints were the 6- and 12-month primary patency rates defined as <50% in-stent stenosis as detected by duplex ultrasound. Clinical endpoints were the cumulative rates of death, amputation, and bypass surgery, as well as improvement in the Rutherford category and the ankle-brachial index. Results were correlated with patient and lesion characteristics., Results: Primary technical success was achieved in all patients, with 1 early stent thrombosis, but no other complications related to the irradiation. Eighty-eight patients reached the 6-month and 82 the 12-month examinations; the primary patency was 95.2% and 79.8%, respectively. In-stent stenosis occurred in 9 patients, while 10 patients had reocclusion of the treated segment. During follow-up, there were 2 late acute thrombotic occlusions, both after discontinuation of clopidogrel. The clinical status improved in 67.0% and 62.2% of the patients after 6 and 12 months, respectively. No patient, lesion, or procedure variables were predictive of restenosis after EVBT., Conclusion: EVBT with liquid beta-emitting Re-188 was safe and effective in preventing restenosis in long-segment femoropopliteal ISS.

Purpose: To describe a technique to approach chronic total occlusions (CTOs) of the superficial femoral artery (SFA) after failed antegrade recanalization as an alternative to a conventional transpopliteal approach., Methods: A retrospective analysis was undertaken of 50 patients (37 men; mean age 71 years) who underwent retrograde recanalization via a distal SFA access after failed antegrade recanalization of SFA CTOs that were not beyond the adductor canal. Antegrade recanalization failed due to flush SFA occlusion, occluded stents, wire perforation, and re-entry failure. Retrograde SFA access required introduction of a 7- to 15-cm, 21-G needle distal to the occlusion. A 0.018-inch guidewire was inserted through the needle followed by a 4- or 6-F, 10-cm sheath or dedicated support catheter only. All retrograde SFA punctures were performed with the patient in the supine position. Once retrograde passage of the occlusion was successful, oftentimes requiring a "double-balloon" technique to disrupt the dissection membrane with abutting balloons delivered from both access sites, balloon angioplasty and/or stenting could be performed from either direction., Results: Retrograde puncture of the distal SFA was successful in all cases. Retrograde recanalization involved insertion of a 6-F sheath in 3 (6%) cases, a 4-F sheath in 32 (64%), and a sheathless approach in 15 (30%). The "double-balloon" technique was necessary to achieve guidewire passage in 12 cases. Recanalization was successful in 48 (96%) cases. Hemostasis time at the distal puncture site was 9.2 minutes (range 3-30). Perioperative complications included 4 pseudoaneurysms (2 groins, 2 distal), 1 peripheral embolization, and 1 small arteriovenous fistula at the distal puncture site., Conclusion: For failure of antegrade recanalization of SFA occlusions, the retrograde SFA puncture distal to the adductor canal with the patient remaining supine is a safe and successful technique that represents a convenient alternative to the conventional transpopliteal approach.

Purpose: To present the 5-year angiographic and clinical results of a retrospective registry assessing the performance of sirolimus-eluting stents (SES) in the treatment of infrapopliteal atherosclerotic disease., Methods: From 2004 to 2009, 158 patients (95 men; mean age 71.9 years) with chronic lower limb ischemia (Rutherford categories 3-6) underwent primary SES placement in focal infrapopliteal lesions. The angiographic endpoint was patency, defined as freedom from in-stent stenosis (ISS) >50%. Clinical endpoints were death, amputation, and bypass surgery. Results were correlated with patient and lesion characteristics and cumulative outcomes were assessed with Kaplan-Meier analysis., Results: Technical success was achieved in all cases. The primary patency rates were 97.0% after 6 months, 87.0% after 12 months, and 83.8% at 60 months. In-stent stenosis was predominantly observed in the first year after stent placement. Female gender was associated with a higher rate of ISS. During clinical follow-up of 144 (91%) patients over a mean 31.1±20.3 months, there were 27 (18.8%) deaths, 4 (2.8%) amputations, and no bypass surgery. Clinical status improved in 92% of the patients with critical limb ischemia (CLI) and 77% of the patients suffering from claudication (p=0.022)., Conclusion: Treatment of focal infrapopliteal lesions with SES showed encouraging long-term angiographic results in this registry. Clinical improvement was evident, but more pronounced in CLI patients than in patients suffering from claudication. Further studies are needed to evaluate the potential clinical benefit of SES as compared to balloon angioplasty or bare metal stents in the treatment of infrapopliteal lesions.

Objectives: The purpose of this study was to investigate the efficacy of drug-eluting balloons (DEBs) in the treatment of long infrapopliteal lesions with regard to the short-term restenosis rate and midterm clinical result., Background: Restenosis rates of long-segment tibial artery disease are very high. Recently, a restenosis rate of 69% at 3 months after standard balloon angioplasty was demonstrated., Methods: Infrapopliteal angioplasty was performed with a paclitaxel-eluting balloon (In.Pact Amphirion, Medtronic, Minneapolis, Minnesota). Clinical and angiographic follow-up was performed at 3 months to detect binary restenosis, and further clinical assessment was performed over a 12-month period thereafter., Results: In 104 patients, 109 limbs were treated for critical limb ischemia (82.6%) or severe claudication (17.4%). Mean lesion length of the arteries treated was 176 ± 88 mm. Angiography studied in 84 treated arteries at 3 months showed a restenosis in 27.4% (19.1% had restenosis of more than 50%, and 8.3% were totally occluded) and usually occurred focally. Only in 9.5% of all angiographically followed up arteries was the entire treated segment restenosed or reoccluded. During a follow-up period of 378 ± 65 days, 1 patient was lost and 17 died. Of the 91 limbs remaining in the analysis, clinical improvement was present in 83 (91.2%). Complete wound healing occurred in 74.2%, whereas major amputation occurred in 4 patients, resulting in limb salvage of 95.6% for patients with critical limb ischemia., Conclusions: The early restenosis rate of long-segment infrapopliteal disease is significantly lower after treatment with DEBs compared with historical data using uncoated balloons. Randomized trials are required to show whether this difference will lead to improvement in clinical outcomes., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Purpose: To report a retrospective, single-center study that evaluates technical and clinical outcomes from subintimal recanalization of femoropopliteal chronic total occlusions (CTO) facilitated by the Outback re-entry catheter., Methods: The Outback catheter was required to complete recanalization of femoropopliteal CTOs (mean lesion length 195 ± 91 mm) in 118 limbs of 113 patients (77 men; mean age 70 ± 10 years). In 80/118 (67.8%) limbs, treatment was performed for claudication and in the remaining 38 (32.2%) for critical limb ischemia (CLI). Technical and procedural success, clinical outcome, and cumulative patency rates in follow-up were evaluated., Results: Re-entry was accomplished in 108/118 limbs (91.5%) with recanalization completed in 107/118 (90.7%). Of these, only 61/107 (57%) arteries were left with a residual stenosis <30%. Complications included minor bleeding of the target vessel (5/118, 4.2%) and minor hematoma/pseudoaneurysm at the access site (6/118, 5.1%). Acute reocclusion developed in 2/118 cases (1.7%) without major complication. After 12 months, primary patency was 56.7%, assisted primary patency 83.1%, and secondary patency 89.1%. Primary patency was significantly reduced in limbs with residual stenosis. Over a median 15-month follow-up (range 2-32), 4 major and 2 minor amputations were performed in patients with CLI., Conclusion: The Outback catheter is a reliable tool to recanalize challenging chronic femoropopliteal occlusions after failed guidewire re-entry. Restenosis rates are high, which may be due to the severity and extent of disease in these patients, who are particularly challenging.

Background and Objective: Restenosis-rate after balloon-angioplasty of long segment tibial arterial disease is largely unknown. We investigated the restenosis-rates angiographically in patients with critical limb ischemia (CLI) due to extensive infrapopliteal lesions., Methods: Angioplasty for infrapopliteal lesions exclusively ≥80 mm in length was performed using dedicated 80-120 mm long low-profile balloons. Follow-up included angiography at 3 months and clinical assessment at 3 and 15 months., Results: Angioplasty was performed in 77 infrapopliteal arteries of 62 limbs of 58 CLI patients with a Rutherford class 4 in 16 (25.8%) limbs and Rutherford class 5 in 46 limbs (74.2%). Average lesion length was 18.4 cm. Treated arteries were stenosed in 35.1% and occluded in 64.9%. After 3 months, a clinical improvement (marked reduction of ulcer-size or restpain) was seen in 47 (75.8%) limbs, 14 (22.6%) limbs were clinically unchanged and 1 (1.6%) limb showed a clinical deterioration. Angiography at 3 months showed no significant restenosis in 24 of 77 (31.2%) treated arteries, a restenosis ≥50% in 24 (31.2%) arteries and a reocclusion in 29 of 77 (37.6%). At 15 months death rate was 10.5%. After repeat angioplasty in case of restenosis cumulative clinical results at 15 months were minor amputations in 8.1%, no major amputations resulting in a limb-salvage rate of 100% with no patient requiring bypass surgery., Conclusions: Restenosis-rate after angioplasty of extensive infrapopliteal arterial disease is high and occurs early after treatment. Despite this the clinical results are excellent, especially given the length of the arterial segments diseased., (Copyright © 2010 Wiley-Liss, Inc.)

Purpose: To present our experience with the use of drug-eluting stents (DES) in patients with symptomatic vertebral artery ostium stenosis (VAOS)., Methods: Between 2003 and 2008, 28 consecutive patients (17 men; mean age 66 years) with symptomatic extracranial vertebral artery stenosis were treated with a paclitaxel-eluting stent. All patients were prospectively scheduled for serial clinical, duplex, and angiographic follow-up to identify restenosis., Results: After stent implantation, the mean stenosis was reduced from 68% to 9%. There were no periprocedural neurological complications. After a mean follow-up of 16 months (range 5-41), no strokes, worsening of symptoms, or deaths occurred. Angiographic restenosis >50% was seen in 6 (21.4%) patients. Restenosis occurred significantly more often in patients with an ipsilateral subclavian artery stenosis (p = 0.01). Radiography during follow-up angiography revealed stent fracture in 1 patient and stent compression/kinking in 11 (39%) of the patients. Stent compression and recoil, not intimal hyperplasia, were the major contributing factors to restenosis., Conclusion: Compared to the restenosis rate of bare metal stents reported in the literature, DES seems to be superior for the treatment of VAOS. However, stent compression and recoil are relevant problems contributing to restenosis. Further improvement of the materials for the interventional treatment of VAOS seems necessary.

Background: The increase in life expectancy results in a higher number of patients with an advanced age over 80 years requiring abdominal aortic aneurysm therapy. The aim of this study was to review the outcome of octogenarians undergoing endovascular treatment for abdominal aortic aneurysms., Patients and Methods: Between June 2004 and March 2008 25 patients (24 males, one female), with a mean age of 83 +/- 2.6 years (range: 80-91 years) underwent elective endovascular treatment for abdominal aortic aneurysms. The average preoperative aneurysm diameter was 57 +/- 9.8 mm (range: 40-80 mm). All procedures were carried out in the angiography suite under general anesthesia., Results: Endovascular abdominal aortic aneurysm repair was technically successful in all patients. There was one perioperative death due to an aneurysm-related complication. The perioperative (30 days) mortality rate was 4 %. Intensive care unit admission was required in five patients. The in-hospital morbidity rate was 20 %. Mean follow-up time was 18.7 +/- 14 months (range: 2 to 47 months). Two patients died from unrelated causes. There were no device- or aneurysm-related deaths. A patient with a type I A endoleak underwent correction by additional stent-graft placement four weeks after initial placement., Conclusion: Endovascular abdominal aortic aneurysm repair in octogenarians is a valuable alternative to open aortic repair and can be performed safely and successfully. We strongly recommend the endovascular treatment for patients over 80 years of age with an appropriate size of aortic aneurysm., (Georg Thieme Verlag Stuttgart.New York.)

Purpose: To describe the technical aspects of the retrograde approach for endovascular treatment of complex popliteal and/or tibioperoneal occlusions and determine its efficacy in minimizing failure rates., Methods: An observational registry of retrograde revascularizations was maintained at our institution over 14 months (September 2006 to December 2007). During this time frame, antegrade revascularization failed in 62 (17.8%) of 343 limbs with complex total occlusions of the popliteal and/or infrapopliteal vascular territory. Of these antegrade failures, 51 (82.2%) limbs in 51 patients (32 men; mean age 72+/-8 years) were suitable for a retrograde attempt. From this subgroup, 45 (88.2%) were treated via a percutaneous transpedal access site and 6 (11.8%) via a transcollateral intra-arterial technique., Results: The overall success rate was 86.3% (44/51); adjunctive stenting was needed in 21 (41.1%) to optimize results. Only 1 (1.9%) major complication (a pedal access site occlusion) and 4 (7.8%) minor sequelae (arterial perforation in 3 and a pedal hematoma without consequence) were documented., Conclusion: In complex popliteal to infrapopliteal occlusions, an antegrade recanalization attempt can fail in up to 20% of the cases. The additional use of a retrograde approach seems feasible and safe and can favorably modify this failure rate. This technique could be valuable for patients with critical limb ischemia due to popliteal and infrapopliteal occlusions once larger studies with follow-up confirm safety, efficacy, and clinical benefit.

Background: Drug-eluting stents have been shown to be very effective in the treatment of coronary artery disease. In this independent, single-centre registry we assess the safety and efficacy of the sirolimus-eluting stent versus bare-metal balloon expandable stent for symptomatic infrapopliteal obstructions., Methods and Results: A total of 60 consecutive patients with infrapopliteal arterial obstructions were treated by stent implantation into the tibial and peroneal arteries and the data was entered into a prospective registry. All patients were treated with balloon-expandable coronary stents with a stent length of 33 mm and a nominal diameter of 3.5 mm. Enrolment was limited to patients treatable with a single stent. 30 patients (56.7% male, mean age 71.4 years, 83.3% diabetics) received a sirolimus-eluting balloon-expandable stent. 30 patients (63.3% male, mean age 73.0 years, 76.6% diabetics) were treated with uncoated bare-metal stents. At follow-up, the cumulative rates of Major Adverse Events were 10.0% vs. 46.6%. The rates of major amputation, bypass surgery or Target Lesion Revascularisation (TLR) were all zero for the sirolimus group compared with 10.0%, 0% and 23.3% in the bare metal stent group. There were 7 deaths (sirolimus =3, bare metal =7). Angiographic follow-up comparing sirolimus vs. bare metal revealed stent occlusion 0% vs. 17.4%, restenosis >50% of 0% vs. 39.1% (p 0.0007) and mean degree of in-stent restenosis of 1.8+/-4.8% vs. 53+/-40.9% (p <0.0001) respectively., Conclusion: In this registry sirolimus-eluting stents were shown to be safe and effective in the treatment of focal infrapopliteal obstructions.

Purpose: Failure to recanalize chronic superficial femoral artery occlusions is frequently caused by subintimal passage of the occlusion with inability to re-enter the true lumen with the guide-wire. The present study details our initial experience with the Pioneer crossing device (Medtronic, Menlo Park, CA) to facilitate recanalization of total femoral artery occlusions., Material and Methods: 25 consecutive patients (18 male, mean age 63 years) whose failed recanalization attempts of chronic superficial femoral artery occlusions (mean occlusion length 12.7 cm) with standard techniques were re-scheduled for a secondary recanalization procedure. The Pioneer crossing device is a 6.2F rapid exchange catheter, which tracks over a 0.014"-wire. A 20MHz phased array IVUS transducer is integrated into the tip of the catheter allowing visualization of the vessel morphology. Using the guidance of the IVUS cross-sectional image supported by colour-flow imaging, the true lumen is punctured with an integrated 24G needle allowing delivery of a second 0.014"-wire., Results: Re-entry into the true lumen was successfully accomplished in all cases without complications. In 8 cases with severe calcification predilatation of the false channel was necessary to allow advancement of the Pioneer crossing device. Furthermore, in 7 patients with severe calcification multiple puncture attempts were necessary to penetrate the dissection membrane. A procedural success (<25% residual stenosis) could be achieved in all cases after predilatation and stenting of the occlusion with self-expanding nitinol stents., Conclusion: The Pioneer crossing device is an effective and save tool to facilitate true lumen re-entry during recanalization of total superficial femoral artery occlusions.

Objectives: The aim of this study was to investigate the occurrence and the clinical impact of stent fractures after femoropopliteal stenting., Background: The development of femoral stent fractures has recently been described; however, there are no data about the frequency and the clinical relevance., Methods: A systematic X-ray screening for stent fractures was performed in 93 patients. In total, 121 legs treated by implantation of self-expanding nitinol stents were investigated after a mean follow-up time of 10.7 months. The mean length of the stented segment was 15.7 cm., Results: Overall, stent fractures were detected in 45 of 121 treated legs (37.2%). In a stent-based analysis, 64 of 261 stents (24.5%) showed fractures, which were classified as minor (single strut fracture) in 31 cases (48.4%), moderate (fracture of >1 strut) in 17 cases (26.6%), and severe (complete separation of stent segments) in 16 cases (25.0%). Fracture rates were 13.2% for stented length < or =8 cm, 42.4% for stented length >8 to 16 cm, and 52.0% for stented length >16 cm. In 21 cases (32.8%) there was a restenosis of >50% diameter reduction at the site of stent fracture. In 22 cases (34.4%) with stent fracture there was a total stent reocclusion. According to Kaplan-Meier estimates, the primary patency rate at 12 months was significantly lower for patients with stent fractures (41.1% vs. 84.3%, p < 0.0001)., Conclusions: There is a considerable risk of stent fractures after long segment femoral artery stenting, which is associated with a higher in-stent restenosis and reocclusion rate.

Objectives: This study sought to compare the efficacy of two different cerebral protection systems for the prevention of embolization during carotid artery stenting (CAS) using a transcranial Doppler (TCD) monitoring with the detection of microembolic signals (MES)., Background: Despite the introduction of cerebral protection systems, neurologic complications during CAS cannot completely be prevented. Transcranial Doppler and detection of MES may aid in assessing the efficacy of different neuroprotection systems., Methods: A total of 42 patients with internal carotid artery stenoses were treated by CAS using either a filter (E.P.I. FilterWire, Boston Scientific Corp., Santa Clara, California) (n = 21) or a proximal endovascular clamping device (MO.MA system, Invatec s.r.l., Roncadelle, Italy) (n = 21). Microembolic signal counts were compared during five phases: placement of the protection device, passage of the stenosis, stent deployment, balloon dilation, and retrieval of the protection device., Results: There were no significant differences in clinical or angiographic outcomes between the two groups. Compared to the filter device, the MO.MA system significantly reduced MES counts during the procedural phases of wire passage of the stenosis, stent deployment, balloon dilation, and in total (MES counts for the filter device were 25 +/- 22, 73 +/- 49, 70 +/- 31, and 196 +/- 84 during the three phases and in total, MES counts for the MO.MA system were 1.8 +/- 3.2, 11 +/- 19, 12 +/- 21, and 57 +/- 41, respectively; p < 0.0001)., Conclusions: In comparison to a filter device the MO.MA system led to significantly lower MES counts during CAS. The detection of MES by TCD may facilitate the evaluation and comparison of different neuroprotection systems.

Transradial arterial access is an alternative approach for coronary interventions. The utilization of these cardiac systems may facilitate endovascular treatment of other vascular territories. This report describes our first experience with percutaneous transluminal renal artery angioplasty and stenting (PTRAS) using the transradial approach. This case demonstrates the feasibility of the radial approach to treat severe renal artery disease safely with PTRAS. Comparison with femoral and brachial arterial access sites is beyond the scope of this paper, but the cardiac literature has demonstrated the safety and efficacy of transradial artery access. With refinement of the endovascular equipment, the radial approach could become an attractive alternative entry site for renal artery interventions.

Percutaneous interventional procedures in the renal arteries are usually performed using a femoral or brachial vascular access. The transradial approach, which has been extensively investigated for coronary angiography and intervention, could be an attractive new technique for renal artery angioplasty and stenting. In 18 patients with hemodynamically relevant unilateral renal artery stenosis (mean diameter stenosis, 83% +/- 18%; right, n = 7; left, n = 11), interventional treatment with PTA and stenting was performed using a left (n = 16) or right (n = 2) radial artery access. Indications for the transradial approach were acute aorto-renal angles or severe peripheral arterial obstructions. After engagement of the renal artery ostium with a 6 Fr Multipurpose guiding catheter (length, 125 cm; Cordis) the stenosis was passed with a 0.014" guidewire followed by stent implantation (ACS Multi-Link RX Ultra, Guidant; length, 18 mm; diameter, 5 mm). Direct stenting was successfully performed in 16 cases. Predilatations were required in two cases. In five patients, optimal stent expansion was achieved by additional postdilatations. A primary technical success (residual stenosis < 30%) could be achieved in all cases. There were no periprocedural complications. According to color-coded doppler ultrasound, all access site arteries showed a normal perfusion. Clinically blood pressure control was improved in 11 patients with a significant reduction in systolic and diastolic blood pressure values. Serum creatinine values dropped from 1.81 +/- 0.3 mg/dl to 1.49 +/- 0.3 mg/dl (P < 0.001). Transradial renal artery angioplasty and stenting is technically feasible and safe. Particularly in patients with unfavorable vessel anatomy, this new cranio-caudal approach is an attractive alternative technique., (Copyright 2001 Wiley-Liss, Inc.)

Purpose: Iliac artery occlusions that are more than a few centimeters in length are normally treated with surgical bypass grafting. The aim of this study was to evaluate the results of primary stent implantation after Excimer laser-assisted recanalization of iliac artery occlusions., Subjects and Methods: We studied 212 consecutive patients with chronic unilateral iliac artery occlusions (mean [+/- SD] length 8.9 +/- 3.9 cm) who were treated with Excimer laser-assisted recanalization and stent implantation. Based on the criteria of the Society of Cardiovascular and Interventional Radiology, lesions were graded as class III occlusions (<5 cm) in 46 patients and as class IV (> or =5 cm) in 166 patients. A total of 527 stents (Palmaz stent, 346; Wallstent, 94; Strecker stent, 38; covered stents, 49) were implanted., Results: Technical success was achieved in 190 (90%) patients. There was a clinical improvement of three grades in 112 (53%) patients and of two grades in 67 (32%) patients. The rate of major complications was 1.4%, which included arterial rupture (1) and embolic events (2). Primary patency rates were 84% at 1 year, 81% at 2 years, 78% at 3 years, and 76% at 4 years. Secondary patency rates were 88% at 1 year, 88% at 2 years, 86% at 3 years, and 85% at 4 years., Conclusion: Stent-supported angioplasty is an effective treatment for iliac artery occlusions, with less morbidity and mortality than is associated with surgery. However, reported long-term patency rates after bypass surgery are greater than those we observed with interventional treatment. The value of primary stenting as compared with angioplasty alone should be evaluated in a randomized trial.

We report about a female patient with intermittent claudication caused by ergotamine. She used ergotamine as a treatment for migraine headaches for more than 4 years. The claudication began 7 month before admission. Colour Doppler sonography and angiography showed severe stenosis of the left external iliac and superficial femoral artery. The patient was treated with phenprocoumon for one year after withdrawal of ergotamine. After that the superficial femoral stenosis disappeared completely, but the external iliac stenosis was still present and was consequently successfully treated by atherectomy. The histology showed a fibrosis of the intima and a hypertrophy of the media.

We report about a 29 year old female who developed right-sided leg vein thrombosis over three levels. Thrombectomy was attempted followed by intravenous anticoagulation with heparin. The platelet count dropped acutely from 176,000/microliter to 11,000/microliter after the sixth day. A lung perfusion-ventilation-scintigraphy suggested recent pulmonary embolism by lateral, predominantly right-sided perfusion deficits. ACT scan of the pelvic region showed rethrombosis of the right common iliac vein. The clinical suspicion of heparin-induced thrombocytopenia (HIT) type II was confirmed by a positive heparin-induced platelet aggregation test and the detection of antibodies by heparin-platelet factor 4-ELISA. The patient was treated with lepirudin at body-weight-adapted dose. After recovery of the platelet count to 102,000/microliter within seven days the treatment was changed to Orgaran after exclusion of immunologic cross reactivity. An overlapping oral anticoagulation with Marcoumar was initiated. Although HIT type II usually develops over a few days, acute thrombopenia can also occur. There is therefore no safe diagnostic interval permitting a timely detection.