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Background: Percutaneous coronary intervention is among the most common therapeutic interventions in cardiology. This procedure may, however, be associated with a rare, though life-threatening complication: acute coronary perforation (CP). CP is primarily treated using covered stents, which are made of bare metal stents with a polytetrafluoroethylene (PTFE) or polyurethane coating. These stents' major limitations include higher rates of thrombus formation and restenosis. Hence, there is a still unmet need for new stents regarding their design and composition. Or, to test new covered stent designs, the rabbit iliac artery has become the best-established animal model. This study sought to present a preclinical animal approach designed to test covered stents that are utilized following vessel perforation., Methods: The animal experiments were performed using New Zealand white rabbits, each weighting 3.5-4.5 kg. The animal models described herein relied on the three most common clinical causes for CP, such as guidewire-induced, balloon catheter bursting, and device oversizing. Moreover, the sealing capacity of covered stent grafts was assessed for each of these models by means of angiography., Results: We herein report a rabbit iliac artery perforation model using three different types of vessel perforation that closely mimic the clinical setting, such as guidewire-induced, balloon catheter rupture, and device oversizing. Using the same rabbit iliac perforation model, we additionally assessed the sealing capacity of a covered stent graft for each model., Conclusions: The novel rabbit iliac artery perforation models, as described in this report, represent promising animal testing approaches. While their setting is very similar to the real-life context encountered in humans, all three models are based on an animal model that is ideally suited for evaluating the sealing capacity and performance of new medical devices for humans.

Objectives: To present results of endovascular treatment of complicated type B aortic dissection., Methods: Patients with acutely complicated type B aortic dissection extending from the left sub-clavian artery to the abdominal aorta were treated. The strategy involved the placement of a covered endoprosthesis to seal the primary entry tear and, in cases where malperfusion persisted, distal extension with uncovered stents, to enhance true lumen (TL) expansion and reperfusion of the ischaemic arterial branches originating from the TL., Results: Thirty-five patients were included. Mean age was 63.1 (37-79) years and malperfusion syndrome occurred in 71.4%. Average aortic coverage with endoprostheses was 220.6 mm (136-355 mm). In 17 cases (48.5%), distal extension with uncovered stents was necessary. Thirty-day major morbidity was 28.5%, and mortality 2.8%. At follow-up (25.6 ± 19.5 months; 4-73 months), overall mortality was 15.2%, and aortic mortality 12.1%. Additional aortic intervention was necessary in 18.2%. Although patients undergoing distal extension with bare metal stents suffered most often from preoperative malperfusion, no significant differences were noted in the 30-day and follow-up clinical results. Follow-up angio-computed tomography showed complete thrombosis of the false lumen in the proximal half of the thoracic aorta in 76.4%. Patients treated with bare stents had significantly larger aortic TL sizes, at the different abdominal aorta levels., Conclusions: In patients with complicated type B aortic dissection, tailored elongation with uncovered stents is a safe treatment of persistent malperfusion. Although the results presented are encouraging, randomized data and a longer follow-up are required to confirm benefits and complications of this strategy., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Whenever some basic rules for endovascular aortic repair of type B aortic dissection are not followed, iatrogenic complications may develop. A 64-year-old gentleman was referred to our institution for revision of previous treatment of complex type B aortic dissection with 2 bare stents. At 3 months, the most proximal aortic bare stent had entered, via the proximal tear, the false lumen. Aortic expansion and dynamic obstruction at the level of the renal arteries had also developed. In a first step, we removed the proximal aortic bare stent surgically. Few days later, 2 covered endografts were implanted into the true lumen of the thoracic aorta with clinical success. The rationale for using endovascular treatment in patients with complicated type B aortic dissection is coverage of the entry tear with covered nonoversized endografts. Negative results are achieved whenever these very simple rules are not strictly followed., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: This study analyzed the outcome of a combined endovascular and debranching procedure for hybrid aortic arch repair (HAR) in patients with complicated type B aortic dissection., Methods: Between February 2006 and August 2012, HAR was performed in 75 consecutive patients, with retrospective analysis of a subgroup of 45 patients who underwent HAR with complicated acute (n = 10), subacute (n = 7), or chronic (n = 28) type B dissection as the underlying disease. Descriptive statistics were computed for continuous and categoric variables. The interval to death or last follow-up was estimated using the Kaplan-Meier method., Results: The patients were a mean age of 59.9 ± 10.7 years (median, 59.2; range, 35-78 years). Complete supra-aortic debranching was performed in six (13%) in zone 0 (procedure time, 200 minutes; range, 185-365 minutes) and partial debranching in 39 (87%), comprising 16 (36%) in zone 1 (procedure time, 120 minutes; range, 75-250 minutes) and 23 (51%) in zone 2 (procedure time, 91 minutes; range, 70-210 minutes). Technical success was achieved in 86.7% (39 of 45). Thirty-day mortality was 4.4% (two of 45), with an in-hospital mortality of 11.1% (five of 45) as a result of three additional deaths after days 33, 35, and 111. Comparing HAR for type B dissection after complete debranching in six and partial debranching in 39, the overall in-hospital mortality was 67% (four of six) and 2.6% (one of 39), respectively. After a median follow-up of 20.8 months (range, 0.3-70 months), the overall mortality was 13.3% (six of 45), with Kaplan-Meier survival estimate of 85% at 1 year. Stroke rate was 8.8% (four of 45). Paraplegia developed in one patient (2.2%), with complete recovery after spinal drainage. Cardiac complications occurred in three patients (6.7%), pulmonary complications in 10 (22.2%), and renal insufficiency requiring dialysis developed in five (11%). Retrograde dissection occurred in one patient (2.2%) 14 days after complete debranching and zone 0 thoracic endovascular aortic repair, with fatal outcome. No bypass dysfunction was seen during follow-up. The overall early and late endoleak rates were 27% (12 of 44) and 43% (13 of 30), respectively. Eight patients (18%) required reintervention, with freedom of reintervention in 91% at 1 year and 81% at 2 years., Conclusions: HAR in zone 1 and 2 appears a viable alternative to conventional aortic arch surgery in patients with complicated type B dissection. Stroke and endoleaks remain complications that need to be addressed. Treatment of type B aortic dissection with complete supra-aortic debranching and thoracic endovascular aortic repair in zone 0, however, is associated with high mortality, which might be reduced by improved technology using branched stent grafts., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Thoracic endovascular aortic repair (TEVAR) represents a therapeutic concept for type B aortic dissection. Long-term outcomes and morphology after TEVAR for uncomplicated dissection are unknown., Methods and Results: A total of 140 patients with stable type B aortic dissection previously randomized to optimal medical treatment and TEVAR (n=72) versus optimal medical treatment alone (n=68) were analyzed retrospectively for aorta-specific, all-cause outcomes, and disease progression using landmark statistical analysis of years 2 to 5 after index procedure. Cox regression was used to compare outcomes between groups; all analyses are based on intention to treat. The risk of all-cause mortality (11.1% versus 19.3%; P=0.13), aorta-specific mortality (6.9% versus 19.3%; P=0.04), and progression (27.0% versus 46.1%; P=0.04) after 5 years was lower with TEVAR than with optimal medical treatment alone. Landmark analysis suggested a benefit of TEVAR for all end points between 2 and 5 years; for example, for all-cause mortality (0% versus 16.9%; P=0.0003), aorta-specific mortality (0% versus 16.9%; P=0.0005), and for progression (4.1% versus 28.1%; P=0.004); Landmarking at 1 year and 1 month revealed consistent findings. Both improved survival and less progression of disease at 5 years after elective TEVAR were associated with stent graft induced false lumen thrombosis in 90.6% of cases (P<0.0001)., Conclusions: In this study of survivors of type B aortic dissection, TEVAR in addition to optimal medical treatment is associated with improved 5-year aorta-specific survival and delayed disease progression. In stable type B dissection with suitable anatomy, preemptive TEVAR should be considered to improve late outcome., Clinical Trial Registration Url: http://www.clinicaltrials.gov. Unique identifier: NCT01415804.

Considering the demographic changes in our society and the proliferation of imaging-based improved diagnostics, both acute and chronic aortic diseases attract increasing attention and require dedicated care. Cardiac as well as vascular surgery used to represent the gold standards for therapeutic management of pathologies of the ascending aorta and the arch; however, the technological evolution of endoluminal strategies has had a serious impact on the treatment of the descending aorta, the aortic arch in combination with vascular debranching or bypass, and in selected cases even on managing pathologies of the ascending aorta. Although several case series and meta-analyses of published observations hint towards superiority of endografting in comparison to open surgical repair, the affected usually multimorbid patients with highly complex aortic disease should be subjected to an individual evaluation by a team of cardiologists, cardiac and vascular surgeons as well as imaging specialists; a dedicated individualized treatment concept in highly experienced centers of excellence is likely to provide the best results for such challenging patients.

Chronic as well as acute diseases of the thoracic aorta are attracting increasing attention, both in the light of an ageing Western and Oriental population and with the proliferation of modern diagnostic imaging modalities. While classic surgical strategies still dominate the treatment of pathology of the ascending aorta and the proximal arch region, new endovascular concepts are emerging and are likely to evolve as primary treatment strategies for descending and abdominal aortic pathology. Additionally, aortic arch pathologies are becoming the target of hybrid approaches combining surgical head-vessel debranching and interventional stent-graft implantation in an attempt to improve outcome by avoiding the high risk of open arch repair or complete replacement. Nonetheless, due to the complexity of the underlying vascular disease, each patient should be discussed in a team consisting of cardiologists, cardiac surgeons, and an imaging specialist in order to design an individualized therapeutic strategy carried out best in a center with experience in both endovascular and surgical procedures.

Objective: Endovascular stent grafting represents a novel concept for type B aortic dissection both in the acute and subacute/chronic setting, with an unknown effect on outcomes., Methods: In a prospective trial 140 patients with stable type B dissection were randomly subjected to elective stent-graft placement in addition to optimal medical therapy (n = 72) or to optimal medical therapy (n = 68) with surveillance (arterial pressure according to World Health Organization guidelines ≤ 120/80 mm Hg). The primary end point was 1-year all-cause mortality, whereas aorta-related mortality, progression (with need for conversion or additional endovascular or open surgical intervention), and aortic remodeling were secondary end points., Results: There was no difference in all-cause mortality: cumulative survival was 97.0% ± 3.4% with optimal medical therapy versus 91.3% ± 2.1% with thoracic endovascular aortic repair (P = .16). Moreover, aorta-related mortality was not different (P = .42), and the risk for the combined end point of aorta-related death (rupture) and progression (including conversion or additional endovascular or open surgical intervention) was similar (P = .86). Three neurologic adverse events occurred in the thoracic endovascular aortic repair group (1 paraplegia, 1 stroke, and 1 transient paraparesis) versus 1 episode of paraparesis with medical treatment. Finally, aortic remodeling (with true-lumen recovery and thoracic false-lumen thrombosis) occurred in 91.3% with thoracic endovascular aortic repair versus 19.4% with medical treatment (P < .001), which is suggestive of continued remodeling., Conclusions: In survivors of uncomplicated type B aortic dissection, elective stent-graft placement does not improve 1-year survival and adverse events, despite favorable aortic remodeling., (Copyright © 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Purpose of Review: Aortic dissection is an uncommon but highly lethal condition with a mortality rate of 1-2% per hour within the first 24 h when the ascending aorta is affected and remains a surgical domain. For the treatment of type B aortic dissection, however, endovascular techniques became available recently and are increasingly popular. This review focuses on current indications and results of thoracic endovascular stent-graft therapy in aortic dissection., Recent Findings: Uncomplicated type B aortic dissections should be managed medically and kept under surveillance for delayed expansion in 20-50% patients over 4 years. Endovascular treatment should be considered in the setting of impending or actual complications, for example, when the aortic diameter exceeds 55-60 mm, in the case of uncontrolled pain or blood pressure with evidence of malperfusion syndrome or rapid growth of the dissecting aneurysm (>1 cm/year). In both complicated acute and chronic type B aortic dissections, endovascular therapy may emerge as an attractive alternative to open surgery. However, in uncomplicated chronic type B aortic dissection, endovascular therapy failed to improve outcomes over optimal medical therapy within 2 years despite aortic remodeling., Summary: Endovascular stent-graft therapy for aortic dissection is emerging with good mid-term results. Further indications, that is, aortic arch dissection and uncomplicated acute aortic dissections, are under evaluation.

Background: Thoracic endovascular aortic repair (TEVAR) represents a novel concept for type B aortic dissection. Although life-saving in acute emergencies, outcomes and survival of TEVAR in stable dissection are unknown., Methods and Results: One hundred forty patients in stable clinical condition at least 2 weeks after index dissection were randomly subjected to elective stent-graft placement in addition to optimal medical therapy (n=72) or to optimal medical therapy alone (n=68) with surveillance (arterial pressure according to World Health Organization guidelines < or =120/80 mm Hg). The primary end point was all-cause death at 2 years, whereas aorta-related death, progression (with need for conversion or additional endovascular or open surgery), and aortic remodeling were secondary end points. There was no difference in all-cause deaths, with a 2-year cumulative survival rate of 95.6+/-2.5% with optimal medical therapy versus 88.9+/-3.7% with TEVAR (P=0.15); the trial, however, turned out to be underpowered. Moreover, the aorta-related death rate was not different (P=0.44), and the risk for the combined end point of aorta-related death (rupture) and progression (including conversion or additional endovascular or open surgery) was similar (P=0.65). Three neurological adverse events occurred in the TEVAR group (1 paraplegia, 1 stroke, and 1 transient paraparesis), versus 1 case of paraparesis with medical treatment. Finally, aortic remodeling (with true-lumen recovery and thoracic false-lumen thrombosis) occurred in 91.3% of patients with TEVAR versus 19.4% of those who received medical treatment (P<0.001), which suggests ongoing aortic remodeling., Conclusions: In the first randomized study on elective stent-graft placement in survivors of uncomplicated type B aortic dissection, TEVAR failed to improve 2-year survival and adverse event rates despite favorable aortic remodeling.

Introduction and Objectives: Postimplantation syndrome that can develop after stent placement is characterized by fever, leukocytosis and an elevated C-reactive protein level or by coagulation disturbances, or by a combination of these features. It is a transient condition that frequently appears following endovascular treatment. At present, no data are available on the effect of antibiotics on postimplantation syndrome after placement of a thoracic endoprosthesis., Methods: This prospective single-center study involved 40 patients. Of these, 20 received peri-interventional (for 24 hours) antibiotic treatment with cefuroxime, 20 mg/ kg three times per day, while 20 received prolonged (for 7 days) treatment at the same dosage. Peripheral blood samples were taken before the intervention and 6 h, 12 h, 24 h, 48 h, 3 days, 5 days, and 7 days after., Results: There was no significant difference in clinical or laboratory findings between the two treatment strategies, and subsequent changes in clinical and laboratory parameters over time were similar in the two groups. All parameters returned to baseline values within 7 days., Conclusions: Prolonging antibiotic treatment beyond the day of endovascular intervention was not observed to provide any short- or long-term clinical benefit in patients with postimplantation syndrome, given that all blood samples were sterile.

The most feared complication after coronary stent implantation is the acutely occurring stent thrombosis, which usually leads to a myocardial infarction with its relatively high mortality. Dual antiplatelet therapy with acetylsalicylic acid and clopidogrel is currently the standard therapy after coronary stent implantation to prevent a life-threatening stent thrombosis. Surgery appears to increase the risk of stent thrombosis, myocardial infarction, and death, particularly when patients undergo surgery early after stent implantation. The incidence of complications is further increased when dual-antiplatelet therapy is discontinued preoperatively. This article reviews the current data of perioperative problems in patients after percutaneous coronary intervention.

Objective: This study examined midterm results after treatment with the endovascular Talent thoracic stent graft (Medtronic/AVE, Santa Rosa, Calif) in patients with acute or chronic aortic dissection., Methods: In the Talent Thoracic Retrospective Registry, 180 patients were treated for acute or chronic aortic dissection (mean age: 59.6 +/- 13.0 years). Thirty-seven (20.6%) patients had acute aortic complications with signs of rupture, distal malperfusion, or persistent pain; the remainder were in stable condition. Aortic diameter was 53.5 +/- 14.3 mm, the distance from the left subclavian artery to the proximal entry tear was 44.1 +/- 41.9 mm, and dissection extended beyond the celiac axis in 88.3% of cases. Length of covered aorta measured 138.9 +/- 45.7 mm, with one stent graft used in 125 (69.4%) patients., Results: Procedural success was 98.3%. Nine patients died within 30 days, yielding an overall early mortality of 5.0%. For in-hospital outcome, multivariate analysis showed that age greater than 75 years (odds ratio [OR] 4,9; 95% confidence intervals [CI] 1.6-15.1; P = .006), American Society of Anesthesiologists class greater than III (OR 2.8; 95% CI 1.0-7.5; P = .04), and emergency status (OR 3.5; 95% CI 1.3-8.9; P = .01) were independent predictors of major adverse events. Compared with electively treated patients, emergency status was associated with a higher incidence of in-hospital mortality (13.5% vs 2.1%; P = .003) and neurologic events (16.2% vs 4.2%; P = .01). However, patients with acute dissection had a smaller baseline diameter and were less often identified to have secondary endoleaks and progressive enlargement. Average follow-up for hospital survivors was 22.3 +/- 17.0 months with an estimated survival of 94.9% +/- 1.7% at 30 days, 90.6% +/- 2.3% at 12 months, 90.6% +/- 2.3% at 24 months, and 81.8% +/- 4.8 % at 36 months. During follow-up, 30 patients required a total of 32 secondary interventions including 12 open and 20 endovascular procedures, accounting for an estimated 71.5% freedom from reinterventions at 36 months. Follow-up imaging revealed stable or decreasing thoracic aortic diameter in 80.5% of patients., Conclusion: Endovascular treatment for aortic dissection is associated with reasonably low morbidity and mortality. Long-term surveillance is crucial to define more comprehensively the durability of stent graft treatment of aortic dissection and to determine which patients are appropriate candidates for stent graft therapy.

Thoracic aortic endografting has demonstrated encouraging mid-term results and attracts growing acceptance as a valuable treatment option for chronic aneurysmal disease. The emerging role of endovascular strategies for management of acute thoracic aortic pathologies is even more exciting considering the sobering results of open repair. Although it is accepted that patients at high risk for open surgery will benefit from endovascular strategies, the exact role of stent-graft interventions remains to be defined as the medical community awaits solid long-term data and better devices. While some indications and scenarios such as acute type B dissection with associated malperfusion syndrome or imminent aortic rupture have shown to benefit from stent-graft treatment, other scenarios are less settled. The current paper discusses both the established and emerging indications, as well as technical and anatomical aspects of this fascinating therapeutic option.

The Marfan syndrome is a heritable disorder of the connective tissue which affects the cardiovascular, ocular, and skeletal system. The cardiovascular manifestation with aortic root dilatation, aortic valve regurgitation, and aortic dissection has a prevalence of 60% to 90% and determines the premature death of these patients. Thirty-four percent of the patients with Marfan syndrome will have serious cardiovascular complications requiring surgery in the first 10 years after diagnosis. Before aortic surgery became available, the majority of the patients died by the age of 32 years. Introduction in the aortic surgery techniques caused an increase of the 10 year survival rate up to 97%. The purpose of this article is to give an overview about the feasibility and outcome of stent-graft placement in the descending thoracic aorta in Marfan patients with previous aortic surgery.

Purpose: To assess the technical feasibility and biocompatibility of a novel stent based on poly(L-lactide) (PLLA) and poly(4-hydroxybutyrate) (P4HB) for peripheral vascular applications., Methods: A polytetrafluoroethylene aortobi-iliac graft was implanted in 5 pigs through a midline abdominal incision. After transverse graft limb incision, 5 PLLA/P4HB stents and 5 metal stents (316L stainless steel) were randomly deployed at both iliac anastomotic sites with 6-mm balloon catheters. Angiography was performed to determine patency prior to sacrifice at 6 weeks. Stented segments were surgically explanted and processed for quantitative histomorphometry. Vascular injury and inflammation scores were assigned to the stented iliac segments., Results: No animals were lost during follow-up. All PLLA/P4HB stents were deployed within 2 minutes by balloon inflation to 8 bars without rupture of the stent struts or anastomotic suture. All stents were patent on postprocedural angiography. Histological analysis showed no signs of excessive recoiling or collapse. PLLA/P4HB stents demonstrated decreased residual lumen area and increased neointimal area after 6 weeks (12.27+/-0.62 and 8.40+/-1.03 mm(2), respectively) compared to 316L stents (13.54+/-0.84 and 6.90+/-1.11 mm(2), respectively) as the result of differences in stent areas (PLLA/P4HB: 4.31+/-0.15 mm(2); 316L: 2.73+/-0.29 mm(2)). Vascular injury scores showed only mild vascular trauma for all stents (PLLA/P4HB: 0.41+/-0.59; 316L: 0.32+/-0.47). Inflammatory reaction was slightly higher around PLLA/P4HB stent struts (1.39+/-0.52) compared to 316L (1.09+/-0.50)., Conclusion: Rapid balloon expansion of PLLA/P4HB stents is feasible without risk of strut rupture. PLLA/P4HB stents provide adequate mechanical stability after iliac anastomotic stenting in pigs. Smaller residual luminal areas in the PLLA/P4HB stents might have been caused by tissue ingrowth into the larger strut interspaces due to higher strut thickness (stent area) in this group. This limitation needs to be addressed in future work on the stent design.

Purpose: To investigate the safety, efficacy, impact on positioning, and neurocognitive outcomes of 3 conceptually different methods of avoiding the "windsock" effect during thoracic stent-graft placement., Methods: A retrospective review was conducted of 70 patients (48 men; mean age 63 years) who underwent elective or emergency stent-graft placement in the thoracic aorta for various pathologies. Twenty-seven patients (18 men; mean age 64+/-12 years) had stent-graft positioning during rapid right ventricular (RV) pacing at 180 to 200 beats per minute. Another 27 patients (18 men; mean age 62+/-12 years) had stent-graft placement under controlled hypotension (

Optimal treatment strategies for pathologies of the descending thoracic aorta are still controversial. Open surgery is complex, while endovascular devices allow nonsurgical access to the thoracic aorta. Endografts can be inserted via a peripheral artery while maintaining aortic blood flow without any need for clamping. Both short- and mid-term outcomes after endografting thoracic aneurysm and type B aortic dissection are encouraging, with significantly lower morbidity and early mortality compared with open surgery. However, despite emerging popularity and growing interest as an alternative to surgery, endograft design and manufacturing have not kept pace with growing clinical ambition. Major challenges associated with endovascular procedures using the current generation of endografts range from the relative rigidity and size of the delivery system to the failure of thoracic endografts to conform snugly to the anatomy of the aortic arch. Nonconformity of grafts may lead to graft instability, endoleak, and procedural failure. Current delivery systems are potentially traumatizing and, at times, too inflexible to track through tortuous, calcified vessels, and often require surgical exposure of the access vessel. Although efforts have been made by the industry to improve conformability and fixation in the aortic arch, given the spiraling movement of the thoracic aorta with each ventricular contraction, much work needs to be done on miniaturization and creation of disease-specific devices. The aim of this work is to give an overview on thoracic aortic stent-graft devices with focus on problems, failure modes and potential improvements.

Background: To assess technical feasibility and biocompatibility of a new Sirolimus (SIR)-eluting biodegradable poly-L-lactide (PLLA) stent for peripheral vascular application., Material and Methods: In 15 pigs, both common carotid arteries (CCA) were surgically exposed and clamped in the proximal segment. After transverse incision, 12 316L stents, 12 unloaded and 6 SIR-loaded PLLA stents mounted on 6.0 x 40-mm balloon catheters were randomly implanted into the CCA and inflated to 8 bar. Angiographic equipment was not available. Stented CCA were explanted after 1 week (6 pigs; 316L versus PLLA) and 6 weeks (9 pigs; 316L versus PLLA versus SIR-PLLA), and processed for quantitative histomorphometry and estimation of vascular inflammation and injury scores., Results: No animals were lost during follow-up. All stents were patent on histological analysis without any signs of excessive recoiling or collapse. Unloaded PLLA stents showed decreased residual lumen area and increased neointimal area after 1 week (13.16 +/- 0.34, 1.94 +/- 0.26) and 6 weeks (11.57 +/- 0.30, 2.85 +/- 0.24) as compared with 316L stents (15.26 +/- 0.13, 1.27 +/- 0.41 and 13.99 +/- 0.51, 1.54 +/- 0.59). SIR-eluting stents demonstrated comparable neointimal area (1.75 +/- 0.38) and 50% lower intimal thickness as compared with 316L stents after 6 weeks, but a slightly decreased residual lumen (13.06 +/- 0.32) in the consequence of differences in strut thickness (PLLA, 270 microm; 316L, 155 microm). The vascular inflammation score against PLLA-stents could be reduced by Sirolimus. The vascular injury scores were low and similar in all groups., Conclusions: PLLA stents showed sufficient mechanical stability after porcine CCA stenting. By incorporation of Sirolimus, a significant reduction of the inflammatory and neointimal response to the PLLA stent was seen without systemic toxicity or thrombotic complications. These findings need to be assessed with longer follow-up to confirm maintenance of efficacy. The greater strut height of PLLA stents is a major limitation and requires modification.

Purpose: To report the use of a technique (PETTICOAT: provisional extension to induce complete attachment) to obliterate sustained abdominal false lumen flow and pressurization despite successful stent-graft sealing of the thoracic entry tear in patients with complicated type B aortic dissection., Methods: Of 100 initial patients subjected to stent-graft repair for complex type B aortic dissection with thoracoabdominal extension, 12 patients (10 men; mean age 58.7 years, range 44-76) demonstrated distal true lumen collapse and a perfused abdominal false lumen despite successful sealing of the proximal tears. As an adjunctive or staged procedure, a scaffolding stent was placed for distal extension of the previously implanted stent-graft. In each case, a Sinus aortic stent, Fortress stent, or a Z-stent system was customized with maximum 2-mm oversizing versus the original stent-graft diameter. Magnetic resonance or computed tomographic angiography was performed at discharge, at 3 months, and then annually to determine false channel thrombosis, true and false lumen dimensions, and re-entry flow., Results: Delivery was successful in all cases (100%). The compressed distal true lumen (mean 4+/-3 mm) was reconstructed to a mean width of 21+/-3 mm, and malperfusion was abolished without any obstruction of the abdominal side branches. At up to 1-year follow-up, there were no signs of expansion or distal progression of the scaffolded dissected aorta. All patients with complete thoracic thrombosis showed evidence of improved aortic remodeling; 1 patient with no false lumen thrombosis died at 11 months from thoracoabdominal aortic rupture., Conclusion: The PETTICOAT technique may offer a safe and promising adjunctive endovascular maneuver for patients with distal malapposition of the dissecting membrane and false lumen flow. The technique can both abolish distal true lumen collapse and enhance the remodeling process of the entire dissected aorta.

Purpose: To assess technical feasibility and biocompatibility of a new biodegradable sirolimus-eluting poly-L-lactide (PLLA) vascular anastomotic stent., Methods: A polytetrafluoroethylene bifurcated graft was implanted in 9 pigs through a midline abdominal incision. After transverse graft limb incision, 6 unloaded PLLAs, 6 sirolimus-loaded PLLAs, and 6 unloaded stainless steel (316L) stents were randomly implanted at both iliac anastomotic sites. Stents were deployed with a 6-mm balloon under direct vision without the use of angiography. Prior to sacrifice after 6 weeks, contrast-enhanced computed tomography (CT) was performed to determine patency of the target vessels. Stented segments were surgically explanted and processed for histology to measure the mean luminal diameter and intimal thickness and to assign vascular injury and inflammation scores., Results: No animals were lost during the study period. All stented graft limbs were patent on CT and histology. At the anastomotic sites and iliac arteries, the mean luminal diameter of SIR-PLLA stents (4.11+/-0.15 and 4.08+/-0.13 mm, respectively) were comparable to metal stents (4.23+/-0.35 and 4.21+/-0.26 mm, respectively), but significantly higher compared to unloaded PLLA stents [3.32+/-0.56 mm (p<0.001) and 3.29+/-0.39 mm (p=0.013), respectively]. At the iliac arteries, the mean intimal thickness was significantly lower with SIR-PLLA stents (0.09+/-0.02 mm) compared to unloaded PLLA stents (0.31+/-0.15 mm, p<0.001) and metal stents (0.19+/-0.04 mm, p=0.004). Vascular injury scores demonstrated only mild vascular trauma for all stents (SIR-PLLA: 0.42+/-0.63, PLLA: 0.51+/-0.62, metal: 0.50+/-0.62). Only mild inflammatory reaction was noted around SIR-PLLA stent struts (1.14+/-0.46), which was comparable to metal stents (1.27+/-0.45) but significantly lower than PLLA stents (1.79+/-0.56, p<0.001)., Conclusion: SIR-PLLA stents showed comparable luminal diameter compared to metal stents, so incorporating sirolimus could reduce the inflammatory and neointimal response to PLLA stents. These findings need to be assessed with longer follow-up to confirm maintenance of efficacy.

Purpose: To assess the technical feasibility, thrombogenicity, and biocompatibility of a new biodegradable poly-L-lactic acid (PLLA) anastomotic stent., Methods: A polytetrafluoroethylene bifurcated graft was implanted in 17 pigs through a midline abdominal incision. After transverse graft incision, 17 316L stainless steel stents and 17 PLLA stents were randomly implanted at both iliac anastomotic sites and deployed with a 6-mm balloon under direct vision without angiography. Intended follow-up was 1 week in 6 pigs receiving oral acetylsalicylic acid (ASA) and in 7 pigs receiving ASA/clopidogrel; 4 pigs receiving ASA/clopidogrel were followed for 6 weeks. At the end of the study, the segments containing the stents were surgically explanted and processed for histology to measure the mean luminal diameter, intimal thickness, and the vascular injury and inflammation scores., Results: Initial technical success of stent placement was achieved in all animals without rupture of the suture. Two pigs died (unrelated to the stent) at 3 days after operation (1 in groups A and B). At 1 week, all PLLA stents showed thrombotic occlusion with the use of ASA alone. In contrast, all PLLA stents remained patent with concurrent administration of ASA/clopidogrel. All metal stents were patent regardless of the antiplatelet regimen. The mean luminal diameter of patent PLLA stents (4.13+/-0.17 mm) was comparable to metal stents (4.27+/-0.35 mm, p=0.78) at 1 week, but significantly diminished at 6 weeks (3.21+/-0.44 versus 4.19+/-0.18 mm, p=0.005). Histological analysis showed no signs of excessive recoil. PLLA stents induced a higher inflammation score (1.79+/-0.56) and more intimal hyperplasia (0.34+/-0.11 mm) compared to metal stents [1.27+/-0.44 mm (p<0.001) and 0.18+/-0.04 mm (p=0.006), respectively] at 6 weeks. Vascular injury was comparable between PLLA and metal stents., Conclusion: Biodegradable PLLA stents showed higher thrombogenicity and reduced patency compared to metal stents during early follow-up. Although ASA and clopidogrel prevented thrombotic occlusion, the increased inflammatory response and neointima formation remain major concerns of PLLA stents. A solution to this problem might be the incorporation of anti-inflammatory drugs into the PLLA stent.

Dual antiplatelet-aggregation treatment with aspirin and clopidogrel after coronary stent implantation is nowadays standard peri-interventional practice, although its use is not yet licensed for this indication in many European countries. Clopidogrel administration is initiated before PCI with a loading dose of 300 mg when given at least 6 hours before PCI, otherwise 600 mg. The required duration of combined (aspirin + clopidogrel) antiplatelet-aggregation treatment after coronary stent implantation depends on the type of stent and the pre-existing disease. After bare-metal stent implantation dual antiplatelet medication is needed for at least 3-4 weeks, after drug-eluting stent implantation 6 months, after coronary brachytherapy 12 months, and 9 months after an acute coronary syndrome. These time intervals should also be respected before any elective surgical intervention. Early operations, because postponement is impossible, should be performed under antiplatelet-aggregation treatment after assessment of bleeding risk in the individual case. Premature termination of this treatment carries an increased risk of serious cardiovascular events, especially stent thrombosis and myocardial infarction. Prolonged antiplatelet-aggregation treatment is of benefit especially in patients with a high risk of serious cardiovascular events. Patients with an indication for long-term anticoagulation may require, during the period of highest risk of stent thrombosis after stent implantation, administration of combined aspirin, clopidogrel and anticoagulants with an INR target value in the lower therapeutic range. The increased risk of bleeding must be weighed up against the potential benefit.

Purpose: To explore the safety and feasibility of stent-graft placement in the dissected descending thoracic aorta of patients with Marfan syndrome., Methods: Six consecutive patients (4 men; mean age 33+/-15 years, range 24-61) with Marfan syndrome were offered endovascular repair for dissection after previous aortic root repair in 5 and solitary type B dissection in 1., Results: Transluminal placement of customized Talent stent-grafts was technically successful in all patients, with no 30-day or 1-year intervention-related mortality. Complete abolition of the dissection and reconstruction of the entire dissected aorta was documented in 2 patients. Over a mean 51+/-22-month follow-up (range 12-74), elective conversion to surgical repair was necessary in 2 patients at 22 and 43 months after stent-graft implantation. In a third patient, conversion to surgery is being considered at 74 months after stent-grafting. One patient died suddenly 12 months after endovascular repair., Conclusions: Nonsurgical reconstruction of postsurgical distal aortic dissection in patients with Marfan syndrome is feasible and technically successful. Stent-graft placement may either avoid or bridge to repeat surgery of distal aortic dissections after previous aortic root repair. Technical expertise and close postinterventional surveillance appear mandatory and may limit the procedure to centers of competence for aortic diseases.

Purpose: To examine the clinical consequences and/or potential need for postinterventional transposition after stent-graft occlusion of the left subclavian artery (LSA)., Methods: The records of 171 consecutive patients (128 men; mean age 60.2+/-13.2 years, range 20-83) undergoing elective stent-graft repair in the thoracic aorta were reviewed to identify intentional endograft coverage of the ostial LSA, as documented by transesophageal echocardiography and/or aortography. Patients were treated for subacute type B dissection, true aneurysm, pseudoaneurysm, or previously operated type A dissection with persistent false lumen flow in the descending aorta. Among the 171 cases, 22 (12.9%) patients were identified with stent-graft occlusion of the LSA., Results: A systolic blood pressure differential existed between the right (138.4+/-14.0 mmHg) and the left (101.8+/-21.0 mmHg; p<0.05) arms after occlusion of the LSA. No patient showed a malperfusion syndrome during postinterventional hospitalization. During a mean follow-up of 24.0+/-15.8 months, 15 (68.2%) patients remained completely asymptomatic, with no functional deficit or temperature differential between the arms, while 7 patients reported mild symptoms of a subclavian steal syndrome. However, no patient required any secondary surgical intervention., Conclusions: Stent-graft-induced occlusion of the ostial LSA was tolerated by all patients without chronic functional deficit. In the absence of stenotic vertebral and/or carotid arteries and with a documented intact vertebrobasilar system, prophylactic transposition of the LSA is not required prior to intentional stent-graft occlusion of the LSA.

Background: Formation of aortic aneurysm late after surgical repair of coarctation carries a significant risk of rupture and lethal outcome, and repeat surgery is associated with a 14% in-hospital mortality rate and morbidity from paraplegia, injury to the central nervous system, or from bleeding. The potential of nonsurgical endovascular repair by the use of stent-grafts in lieu of repeat surgery for postcoarctation aneurysm is unknown., Methods and Results: The concept of postsurgical endovascular stent-graft placement was evaluated with respect to feasibility and safety in 6 consecutive patients with late aneurysm formation after coarctation repair. All patients had aneurysm formation late after patch aortoplasty; placement of an elephant trunk during surgical repair of secondary type I dissection preceded formation of a local aneurysm in 2 cases. Patient age was 49+/-12 years, ranging from 31 to 68 years. Transluminal placement of customized stent-grafts was successful, with no 30-day or 1-year intervention-related mortality or morbidity. Follow-up survey of 11 to 47 months revealed optimal reconstruction of the thoracic aorta; 1 patient died 11 months after endovascular repair from cancer., Conclusions: Nonsurgical aortic reconstruction of postsurgical thoracic aneurysms forming late after coarctation repair is safe and feasible; interventional stent-graft placement has the potential to avoid repeat surgery of postsurgical aortic aneurysm.

Background: Even with rapid diagnosis and effective medical treatment mortality in type B aortic dissection with evidence of extraaortic leakage of blood remains high. Considering a mortality rate of 29% to 50% associated with emergency surgical repair, the concept of endovascular stent-graft placement may become a life-saving option in impending or evolving rupture by endovascular sealing of the entry tear and subsequent abortion of leakage., Methods: The concept was tested by comparing short-term and 1-year outcomes of 11 patients after emergency endovascular stent-graft placement with historic-matched control patients subjected to conventional therapy. All patients had acute type B dissection complicated by loss of blood into periaortic spaces., Results: Emergency stent-graft placement was successful without periprocedural morbidity, aborted leakage, and ensured reconstruction of the dissected aorta; at a mean follow-up of 15 +/- 6 months no death had occurred in the stent-graft group whereas four patients had died with conventional treatment (p < 0.05)., Conclusion: With appropriate logistics and expertise, type B aortic dissection with leakage and evolving rupture may benefit from nonsurgical reconstruction of the dissected segment by endovascular stent grafts.

Descending thoracic and abdominal aortic aneurysms represent a potential life-threatening situation. Resection and graft replacement of the pathologically altered aorta used to be the preferred method of treatment. Although progress has been achieved during the past decades in the management of patients with thoracic aortic aneurysms by new surgical techniques, intraoperative monitoring of somatosensory-evoked potentials, and spinal cord fluid drainage, postoperative morbidity and mortality rates still remain high. The afflicted population is usually of older age and present at the time of operation with various comorbidities such as hypertension, obstructive pulmonary disease, coronary heart disease, all of which with significant impact on surgical outcome. Postoperative complications, such as paraplegia, renal and pulmonary disease, contribute to prolonged hospital stay and higher medical cost. In this review we report on a promising alternative approach to the surgical treatment of thoracic and abdominal aortic aneurysms, namely the currently emerging utilization of the endovascular stent-graft prosthesis in both thoracic and abdominal aneurysm.