Stent Coverage Research Articles

Outcomes Using Uncovered Stents and Covered Stents Are Similar for Management of Chronic Mesenteric Ischemia: A Single-Center Retrospective Experience

Endovascular treatment of chronic mesenteric ischemia (CMI) has been shown to have similar perioperative mortality and shorter hospitalization compared with open repair but increased reinterventions due to restenosis. Covered stents (CSs) are associated with less restenosis, recurrence of symptoms, and reinterventions than bare-metal uncovered stents (UCSs). This study intends to revisit endovascular management of CMI and to evaluate differences in patients who received CSs or UCSs. Clinical data were obtained retrospectively for CMI patients at a single center from 2010 to 2015. Patients included were treated with either UCS or CS, were diagnosed with CMI, and had radiographic evidence of mesenteric disease. Patients who were excluded had acute mesenteric ischemia or procedures performed at an outside hospital. Sixty patients with an average age of 70.7 ± 9.4 years were involved in the study. Comorbidities included type 2 diabetes (21/60), hypertension (51/60), hyperlipidemia (51/60), and smoking history (52/60; Table I). Fisher exact test was performed, and there was a difference between the specific mesenteric vessel intervention completed and the number of diseased mesenteric vessels (P < .001). No difference was seen between UCS and CS with vessel intervened on (P = .290). There was no significant difference in symptom recurrence (48.8% vs 42.1%), reintervention rates (34.2% vs 26.3%), number of reinterventions (1 [1-4] vs 1 [1-2], median [range]), or hospital length of stay (1 [0-28] days vs 1 [0-8] days) between UCS and CS interventions, respectively (P > .05). Reintervention rates were similar despite antiplatelet regimen (no antiplatelet, 40%; single antiplatelet, 48.4%; or dual antiplatelet, 47.4%; P > .05). No significant difference in death rate (43.9% vs 68.4%) was seen, and all-cause mortality from index operation was 2.6 years (0.1-7.2 years; Table II). In this retrospective review, there was no significant difference in success rate for revascularization, recurrence, or complications with the use of CSs or UCSs. Larger randomized studies may be needed to determine the superiority of one stent type over another.Table IDemographics of patients receiving uncovered stents (UCSs) and covered stents (CSs) for chronic mesenteric ischemia (CMI)Age, years70.7 ± 9.4Type 2 diabetes35%Sex63.3% MHypertension85%36.7% FHyperlipidemia85%Total patients60Smoking86.70% Open table in a new tab Table IIDifferences in outcomes between interventions completed for uncovered stents (UCSs) and covered stents (CSs)UCSsCSsSymptom recurrence48.8042.10Incidence of reintervention34.2026.30Total No. of reinterventions1 (1-4)1 (1-2)Hospital length of stay, days1 (0-28)1 (0-8)Death rate43.9068.40Categorical variables are presented as percentage. Continuous variables are presented as median (range). Open table in a new tab

Clinical Outcomes After Implantation of Polyurethane-Covered Cobalt-Chromium Stents: Insights from the Papyrus-Spain Registry

Background/purposeThe main indication of covered stents (CS) is coronary artery perforation (CAP), but, they have been increasingly used in other scenarios. Data on the long-term follow-up of CS is limited, and no studies have been conducted specifically using new-generation polyurethane-covered cobalt-chromium Papyrus CS. Purpose: to evaluate the clinical outcomes after hospital discharge of Papyrus CS and to compare their outcome after implantation in CAP or coronary artery aneurysms (CAA). Methods/materialsWe evaluated the baseline clinical characteristics, lesion subsets, procedural features and the outcomes after initial discharge of Papyrus CS implanted in 17 high-PCI-volume centers. Results127 Papyrus CS were implanted in 108 patients (68 ± 1 years; 82.8% male) admitted for stable coronary disease (32.3%), NSTEMI (42.4%) or STEMI (25.3%). The number of CS per patient was 1.2 ± 0.6 (diameter: 3.5 ± 1.7 mm; length: 18.5 ± 3.7 mm). Angiographic success rate was 96%. CS diameter was larger in CAA (CAP:3.04 ± 0.5 mm vs CAA:4.1 ± 2.7 mm; p = .022). Intracoronary imaging techniques were used more frequently in CAA (p < .0001). After a mean follow-up of 22 ± 16 months, the major cardiovascular adverse events (MACE) rate was 7.1% [cardiac death: 2%, Myocardial infarction: 5%, Target Lesion Revascularization: 5% and Stent Thrombosis (ST): 3%]. MACE rate was similar in CAP (7.7%) and CAA (7.1%) (p = .9). However, CAA showed a higher ST rate (CAP: 0% vs CA: 7.1%; p = .04). ConclusionAfter hospital discharge, clinical outcomes after Papyrus CS implantation are acceptable (considering the clinical scenario and compared with other treatment alternatives) with no significant differences in the MACE rate between those implanted in CAA or in CAP. However, CAA group showed a higher ST rate.

Drug Eluting Stents Versus Bare-Metal and Covered Stents in the Femoral-Popliteal Vessels, a Single Center Experience

To compare mortality and patency rates of drug-eluting stents (DES) versus bare metal (BMS) and covered stents in patients who underwent stenting of femoropopliteal arteries for peripheral arterial disease.

Midterm Results of the Treatment of Penetrating Abdominal Aortic or Iliac Artery Ulcer with the BeGraft Balloon-Expandable Covered Stent—A Single-Center Experience

The purpose of the study was to evaluate the feasibility and efficacy of the novel BeGraft covered stent for the treatment of abdominal penetrating aortic ulcer (PAU) or penetrating ulcers of the iliac arteries (PUIAs). This was a single-center observational study, which included 24 consecutive patients who underwent endovascular surgery due to abdominal PAU or PUIA between June 2017 and September 2019. Demographics of patients, lesion characteristics, diameter and length of the BeGraft stents, and postoperative events were prospectively collected and retrospectively analyzed. Follow-up examinations were performed at 1, 6, 12, and 24months with clinical and hemodynamic evaluation. Outcome measures included technical success, perioperative complications, and stent patency. A total of 24 patients (13 men and 11 women), with a median age of 67years (range, 42-81years), were analyzed. Among them, 20 patients were symptomatic, and 4 patients underwent elective surgery because of the size of PAU. A total of 54 BeGraft stents (26 aortic and 28 peripheral) were successfully delivered and deployed to cover 13 aortic and 13 common iliac artery ulcer lesions. The technical success rate was 100%. The average procedural time was 53.8±12.8min. Complications included one case of the access-site pseudoaneurysm, which was successfully treated by thrombin injection. During a median follow-up of 20.5months (range, 6-33months), all stents remained patent, without endoleak or ulcer recurrence. BeGraft stents used during endovascular treatment of abdominal PAU and PUIA lesions are associated with favorable outcomes regarding technical success and patency. The primary use of BeGraft covered stents provides a valid option for patients with abdominal PAU. Long-term follow-up is required to confirm these promising results.

The impact of therapeutic mediastinal radiation on stent healing in cancer patients: An optical coherence tomography study.

e19096 Background: Cancer is a prothrombotic and proinflammatory state. Understanding stent healing in cancer patients could modify the approach to antiplatelet regimen and facilitate cancer treatment. Mediastinal radiation therapy brings an additional layer of complexity to an already challenging clinical scenario in cancer patients undergoing percutaneous coronary intervention (PCI). We sought to compare stent healing patterns with and without a history of mediastinal radiation therapy using optical coherence tomography (OCT) data. Methods: All cancer patients that underwent PCI and follow-up OCT less than 12 months post-PCI between 2009-2018 were retrospectively identified from our institutional cardiac catheterization laboratory registry. Stent healing, which was defined by a combination of stent and strut coverage, apposition, expansion, in-stent restenosis, and neo-intimal hyperplasia, was compared among 2 groups of oncological PCI patients: those with and without a history of mediastinal radiation therapy. Differences among the two categories were assessed using linear-effect models. Results: There were 86 cancer patients who received PCI with follow-up OCT within 12 months. Of these, 22% received mediastinal radiation. There was no statistical difference in baseline characteristics (hypertension, dyslipidemia, diabetes, etc.) between the two studied groups. In the non-radiation group, 59% were late stage or advanced cancer patients, while 63% of patients in the radiation group were advanced cancer patients. Stent healing was similar among those who had received radiation therapy and those who had not (Table). Conclusions: A history of mediastinal radiation does not appear to affect early stent healing within 1 year of PCI. Given stent healing appears to be similar with or without radiation, dual anti-platelet therapy regimens may not need to change based on radiation exposure alone. Future studies should address the duration of dual antiplatelet regimens and long-term outcomes (i.e. in-stent restenosis) based on stent healing properties. [Table: see text]

Meta-Analysis Comparing Endovascular Treatment Modalities for Femoropopliteal Peripheral Artery Disease

Endovascular interventions are commonly utilized for treatment of femoropopliteal peripheral artery disease. The relative efficacy of these interventions remains unclear. A Bayesian network meta-analysis was performed comparing 5 endovascular treatment modalities: balloon angioplasty (BA), bare metal stent (BMS), covered stent (CS), drug-coated balloon (DCB), drug-eluting stent (DES) for femoropopliteal peripheral artery disease. The primary efficacy end points were freedom from target lesion revascularization (TLR) and primary patency at 12 months. BA was the reference treatment. Twenty-two trials including 4,381 participants provided data on TLR. Sixteen trials including 3,691 participants provided data on primary patency. Point estimates for DCB suggested that it was the most efficacious treatment for freedom from TLR (odds ratio [OR] 4.23; 95% credible intervals [CrI] 2.43 to 7.66) followed by CS (OR 3.65; 95% CrI 1.11 to 12.55), DES (OR 2.64; 95% CrI 0.72 to 9.77), and BMS (OR 2.3; 95% CrI 1.11 to 4.76). Similarly, point estimates for primary patency were highest with DES (OR 8.93; 95% CrI 3.04, 27.14) followed by CS (OR 3.91; 95% CrI 1.18, 13.84), DCB (OR 3.32; 95% CrI 1.8, 6.25), and BMS (OR 3.5; 95% CrI 1.58, 7.99). In conclusion, DCB has the lowest need for TLR whereas DES has the highest primary patency rate. DCB, CS, and BMS were associated with significant reductions in TLR compared with BA, whereas DCB, DES, CS, and BMS were associated with significantly improved primary patency compared with BA.

Application of the Willis Covered Stent in the treatment of intracranial unruptured aneurysms in internal carotid artery: A retrospective single-center experience

The purpose of this study was to retrospectively analyse the clinical and angiographic outcomes of Willis covered stent placement for unruptured aneurysms in internal carotid artery. Forty-six consecutive patients with internal carotid artery aneurysms (49 cases) were included to evaluate clinical and angiographic outcomes. Covered stent placement was successful in 47 cases, whereas stent navigation failed in 2 cases. Of the 49 aneurysms (mean aneurysm size, 7.9 mm), 5, 6, and 38 were located in the petrous, cavernous, and ophthalmic segments, respectively. Immediate angiography revealed complete aneurysm exclusion in 36 (76.6%) cases, whereas minimal endoleak was observed in 11 cases. Four patients had procedure-related complications, including 1 patient with acute in-stent thrombosis, 2 with a post-operative subarachnoid haemorrhage, and 1 with artery rupture. Angiographic and clinical follow-up was available for 36 patients (38 aneurysms). Complete aneurysm occlusion was achieved in 34 (89.5%) cases, endoleak was present in 2 cases, and aneurysm recurrence occurred in 2 cases. Asymptomatic in-stent stenosis was observed in 3 patients. No hemorrhagic or ischemic events occurred during the follow-up period. At follow-up, the modified Rankin scores were 0–2 for 35 patients and >2 for 1 patient. Satisfactory angiographic outcomes were achieved in our study. However, the risks of stent navigation failure, endoleak after balloon re-inflation, procedure-related complications and coverage of side branches should be considered when choosing the best therapeutic option for internal carotid artery aneurysms.

Multivariable prediction model to estimate the probability of restenosis at proximal edge after 2nd-generation drug-eluting-stent implantation: development and internal validation using a quantitative coronary angiography from the post-marketing surveillance studies of everolimus-eluting stent in Japan

Edge restenosis has still been reported after second-generation drug-eluting stent (DES) implantation. It was more likely attributable to post-procedural angiographic results than to the patient's background. The aim of this study was to develop and internally validate a prediction model for restenosis in proximal edge after 2nd-generation DES stent implantation using angiographic data. Data were obtained from several post-marketing surveillance (PMS) studies of the cobalt-chromium everolimus-eluting stent (CoCr-EES) and platinum-chromium everolimus-eluting stent (PtCr-EES), second-generation DES, in Japan. Angiographic analysis was conducted at baseline and after 8 or 12months. We focused on the proximal edge of angiographic analysis. The main outcome was restenosis defined as ≥ 50% diameter stenosis at follow-up. The predictive performance of the prediction model based on multivariable logistic regression was assessed in terms of discrimination and calibration, which were internally validated by the bootstrap method. We also performed decision curve analysis to assess threshold of predicted probability of restenosis at which additional intervention was considered. Among 2053 lesions in 1860 patients, restenosis rates in proximal edge was 2.8%. The final model was constructed with % post-procedural diameter stenosis (DS) and post-procedural reference diameter (RD) as strong predictors for edge restenosis. Discrimination and calibration were satisfactory with optimism-corrected C-statistics 0.75. Predicted probability between 0.03 and 0.24 was preferable threshold for restenosis treatments. Our prediction model can be used to obtain valid prediction for restenosis in proximal edge, assisting to know complete stent coverage of lesion.

The Role of Endovascular Stents in an Experimental Model of Traumatic Arterial Occlusion – the Temporary Endo-Shunt

Background.We aimed to evaluate patency following the deployment of a bare-metal (BMS) or covered stent (CS) across a traumatic occlusive arterial lesion and to estimate the feasibility of urgent stent placement for temporary endovascular shunting.&#x0D; Methods. Fifteen sheep (25-45 kg) underwent laparoscopic creation of a left external iliac artery (EIA) thrombosis by means of repeated clamping. Animals were then randomized into one of three groups: no-treatment (control group), a BMS group or CS group. Animals were followed up for 30 days with no anticoagulants or anti-platelet drugs administered postoperatively. Doppler ultrasound, computed tomography angiography (CTA), and digital subtraction angiography (DSA) were used to evaluate EIA patency.&#x0D; Results.Stent implantation resulted in the restoration of in-line flow through the EIA in all cases. The peak systolic velocity (PSV) in the injured limb increased from 10 (0–16) to 31 (28–37) cm/sec in the BMS group (p&lt;0.0001) and from 15 (7–18) to 24 (21–29) cm/sec in the CS group (p=0.043) immediately after stent deployment (both p=0.001 compared to the control group). There was no difference in the PSV between the groups at post-injury day 3, and thereafter. Day-14 CTA and day-30 DSA demonstrated only one patent stent in each study group.&#x0D; Conclusions.Stent (BMS or CS) implantation restores arterial patency of a traumatic occlusive lesion for a period of less than three days in our ovine model. While acute recanalization of the injury with stent implantation may be used for temporary endovascular shunting, long-term patency remains a problem.

Parallel Covered Stents Technique in the Treatment of Abdominal Aortic Diseases

PurposeTo investigate the safety and efficacy of the parallel covered stents technique in the treatment of anatomically challenging aortic aneurysms, pseudoaneurysms, and dissections. Materials and MethodsData were retrospectively collected from 16 patients with abdominal aortic diseases who were treated with parallel covered stents (Gore Excluder, n = 14; Medtronic Endurant, n = 2) between January 2016 and July 2018. Patients were treated with this technique if they were unsuitable for either open repair or standard endovascular aortic repair with bifurcated stents. Such unfavorable anatomy included narrow aortic necks (≤18 mm), small vascular access (occluded or ≤6.0 mm), or compressed aortic lumens (≤18 mm). All patients were male, with a mean age of 64.7 ± 13.3 years. For true aneurysms (n = 4) and pseudoaneurysms (n = 4), the mean diameter and length of the proximal necks were 17.5 ± 2.6 mm (range, 14–21 mm) and 51.0 ± 12.5 mm (range, 39–75 mm), respectively. The minimal diameter of true lumen in cases with aortic dissection and penetrating ulcers (n = 8) was 14.8 ± 3.1 mm. Small or occluded femoral access was found in 3 patients. ResultsTechnical success was 100%. Minor type I endoleaks, which were seen on completion angiography in 5 patients, had all resolved within 3 months. There were no perioperative deaths. Postoperative complications included supraventricular tachycardia in 1 patient and pneumonia combined with heart failure in 1 patient. Patency of all stents was observed at a mean follow-up of 21.8 ± 10.1 months. ConclusionsThe parallel covered stents technique appears to offer a feasible solution for abdominal aortic diseases with unfavorable anatomy. Long-term follow-up is needed to further evaluate the safety and efficacy of this technique.

Application and Evaluation of Highly Automated Software for Comprehensive Stent Analysis in Intravascular Optical Coherence Tomography

Intravascular optical coherence tomography (IVOCT) is used to assess stent tissue coverage and malapposition in stent evaluation trials. We developed the OCT Image Visualization and Analysis Toolkit for Stent (OCTivat-Stent), for highly automated analysis of IVOCT pullbacks. Algorithms automatically detected the guidewire, lumen boundary, and stent struts; determined the presence of tissue coverage for each strut; and estimated the stent contour for comparison of stent and lumen area. Strut-level tissue thickness, tissue coverage area, and malapposition area were automatically quantified. The software was used to analyze 292 stent pullbacks. The concordance-correlation-coefficients of automatically measured stent and lumen areas and independent manual measurements were 0.97 and 0.99, respectively. Eleven percent of struts were missed by the software and some artifacts were miscalled as struts giving 1% false-positive strut detection. Eighty-two percent of uncovered struts and 99% of covered struts were labeled correctly, as compared to manual analysis. Using the highly automated software, analysis was harmonized, leading to a reduction of inter-observer variability by 30%. With software assistance, analysis time for a full stent analysis was reduced to less than 30 minutes. Application of this software to stent evaluation trials should enable faster, more reliable analysis with improved statistical power for comparing designs.

Comparative Effectiveness of Endovascular Treatment Modalities for De Novo Femoropopliteal Lesions: A Network Meta-analysis of Randomized Controlled Trials

Purpose: To report the results of a network meta-analysis of randomized controlled trials (RCTs) comparing multiple endovascular treatments for de novo femoropopliteal lesions. Materials and Methods: The MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials databases were systematically searched on June 1, 2019, for prospective RCTs comparing 14 treatments [ie, atherectomy, brachytherapy, cryoplasty, cutting balloons, drug-coated balloons, bare nitinol stents, drug-eluting stents (DES), covered stents (CS), and combinations] in the treatment of de novo femoropopliteal lesions. Outcomes were technical success; binary restenosis and target lesion revascularization (TLR) at 6, 12, and/or 24 months; and all-cause mortality at 12 months. Ultimately, 53 articles reporting on 45 studies (91 study arms; 5565 patients) were selected. For the technical success outcome, all types of stents, all balloons, and all atherectomy devices were aggregated in stent, balloon, and atherectomy technology groups, respectively. Results: In terms of technical success for aggregated treatment types, stent technology was the most effective treatment and was better than balloon and atherectomy technologies. In terms of binary restenosis, DES was the most effective single treatment at the 6- and 12-month follow-up and CS at the 24-month follow-up. Both DES and CS were better than the majority of other single treatments, including balloon angioplasty, cutting balloon, cryoplasty, directional atherectomy, and bare nitinol stent during all follow-up periods. In terms of TLR, DES was the second most effective single treatment and the most effective single treatment at the 6- and 12-month follow-up intervals; CS was the most effective single treatment at the 24-month follow-up. Both DES and CS were better than the majority of other single treatments. The 12-month all-cause mortality of both DES and CS were similar to other treatments, whereas cryoplasty seemed to be the least effective treatment with regard to binary restenosis and TLR. Conclusion: Both DES and CS had substantial advantages in terms of restenosis and TLR in femoropopliteal lesions and were similar to aggregate stent technology in terms of technical success. DES performed better within 12 months after operation and CS at ~24 months, but neither had much advantage in terms of mortality. In contrast, cryoplasty seemed to be a less effective treatment.

Covered Stents Versus Uncovered Stents in the Treatment of Supra-Aortic Trunks Occlusive Disease

Introduction - Published reports on endovascular treatment of supra-aortic trunks occlusive disease (SATOD) are relatively scarce, with a limited numbers of cases1. Results still show a high rate of restenosis1-5 that could possibly be improved by the use of covered stents. To our knowledge, no study has been published to evaluate the use of covered stents in this location. The aim of our study is to compare the rate of restenosis and patency after endovascular treatment of SATOD using covered stents (CS) versus uncovered stents (UCS). Methods - This was a retrospective study compiling consecutive cases of stenting angioplasty for SATOD performed between July 2008 and January 2017 in our academic institution. We defined 2 groups: CS and UCS depending on the type of stent we used. Demographic characteristics, clinical presentations, procedures details and outcomes were recorded. We considered all restenosis when higher than 50%. Results - Sixty-two supra-aortic trunks were treated in 54 patients. Twenty-nine cases were included in Group CS and 33 in Group UCS. Mean age was 65.8 ± 1.4 [38.8 - 86.5] years. The lesions treated were the left subclavian artery (n=32, 51.6%), the brachiocephalic artery (n=16, 25.8%), the right subclavian artery (n=10, 16.1%) and the left common carotid artery (n=5, 8.1%). Thirty-seven (59.7%) lesions were symptomatic and seven (11.3%) were occlusions. The mean follow-up was 27.6 ± 3.1 [0.03 - 103.1] months. Only 2 patients (3.2%) with one lesion each were lost to follow-up. The characteristics of the patients were comparable between both groups in terms of age, sex and type of lesions. The average time of restenosis was 23.4 ± 4.4 [0.1 - 54.1] months. The overall restenosis rate was 6.9% in Group CS and 36.4% in Group UCS (p = 0.006). Tight restenosis (greater than 70%) rate was 6.9% in Group CS and 12.1% in Group UCS (p = NS). Survival without restenosis was 85.9% and 82.1% at 2 years and 85.9% and 72.6% at 3 years in Group CS and Group UCS respectively (p = NS). The primary and secondary patency rates at 2 years were 100% in Group CS and 96.9% in Group UCS (p = NS). Conclusion - Compared to UCS, CS appears to have an advantage in term of restenosis for the treatment of SATOD. However, short and mid-term patency was comparable between these two kinds of stent. Further randomized studies should be proposed.

Validation of post-stenting fractional flow reserve with intravascular ultrasound parameters for optimal stent deployment.

We aimed to evaluate the relationship between post-stent fractional flow reserve (FFR) and intravascular ultrasound (IVUS) parameters for stent optimization. IVUS and FFR measurements were performed in 101 coronary lesions after successful percutaneous coronary intervention (PCI). Quantitative IVUS parameters for stent optimization such as minimal intra-stent cross sectional area (CSA), proximal, and distal reference lumen CSA, and plaque burden (PB) at both edges of the stent related to the post-stent FFR. Mean post-stent FFR was 0.91 ± 0.06. Post-stent FFR ≤ 0.90 was observed in 46 (45.5%) lesions. The 55 lesions with post-stent FFR > 0.9 had larger proximal CSA (9.2 ± 2.9mm2 vs. 7.4 ± 2.3mm2, p = 0.001), distal reference lumen CSA (7.4 ± 2.7mm2 vs. 6.3 ± 2.1mm2, p = 0.017), minimum intra-stent lumen CSA (7.4 ± 2.5mm2 vs. 6.1 ± 1.7mm2, p = 0.004), and lower proximal reference PB (45 ± 8.2% vs. 50 ± 11%, p = 0.017) than did those with post-stent FFR ≤ 0.90. Post-stent FFR had an inverse correlation with age, left anterior descending artery (LAD) against non-LAD, and proximal reference PB and a positive correlation with pre-stent FFR, proximal and distal reference lumen CSA, and minimum intra-stent lumen CSA. Meanwhile, no correlation was found between post-stent FFR and stent length. Pre-stent FFR (β = 0.544), proximal reference lumen CSA (β = 0.530) and age (β = - 0.251) were found to be independently associated with the post-stent FFR. Post-procedural FFR might partly reflect the appropriateness of PCI results in terms of the adequate expansion of the stent and full lesion coverage on IVUS.

Post-stEnting assessment of Re-endothelialization with optical Frequency domain imaging aftEr Chronic Total Occlusion procedure: The PERFE-CTO Study Design and Rationale

BackgroundThe treatment of chronic total occlusion of coronary arteries by percutaneous coronary intervention (CTO PCI) is one of the most representative technical advances in ischemic cardiomyopathy of last decade. However, how the complex histopathological remodeling and the new techniques affect healing processes after stent implantation remains unknown. ObjectiveThe objective of the PERFE-CTO study is to analyze stent coverage, malapposition and other mechanical abnormalities 3 months after CTO recanalization using intravascular imaging. MethodsIn a French prospective interventional multicenter study, stent strut coverage, acquired malapposition and neointimal hyperplasia (NIH) proliferation will be systematically assessed with 3 months angiogram control and intracoronary optical frequency domain imaging (OFDI) after successful CTO PCI of >20 mm in length. The impact of routine systematical intracoronary imaging after these complex procedures will also be evaluated by measuring the rate of significant mechanical abnormalities (strut malapposition, edge dissection, thrombus) that was undetected by fluoroscopy alone and by complementary PCI when needed. Secondarily, these data will be compared according to clinical characteristics, antiplatelet therapy use or desobstruction technique (antegrade vs. retrograde, true lumen vs. subintima). Each patient will undergo a one-year clinical follow-up. A total of 150 analyzed CTO lesions is expected. ConclusionThe PERFE-CTO study will provide essential understanding of the early history after CTO recanalization and the identification of inadequate evolution (stent thrombosis, restenosis or late delayed stent endothelization and cardiovascular outcomes) using intravascular imaging to improve long-term CTO results.

Optimization of a Novel Preferential Covered Stent through Bench Experiments and in Vitro Platelet Activation Studies

A newly designed BMS was developed and compared to a commercially available peripheral stent. Two materials (expanded poly(tetrafluoroethylene)) and silicone polyurethane co-polymers (Elast-eon E2A) were used as stent coverings with slits applied using various cutting methods to form the PCS. These PCS samples were tested for physical resilience, flexibility, ability to preserve side-branch flow, slit edge roughness, and platelet activation. Fabrication of E2A-coated stents required pretreatment of the stent with poly(ethylene glycol) to achieve firm attachment. The newly designed BMS with nine crowns design and larger cell size showed higher flexibility than commercially available stents. A combination of a larger stent cell size, E2A membrane coating, and three slits per stent cell unit configuration resulted in preserved side-branch flow similar to physiological conditions in the flow experiment. Slit edge roughness changed with different cutting methods and laser machine cutting parameters. In vitro studies showed platelet activation was minimal with lower slit edge roughness samples. An optimized PCS prototype was developed consisting of a newly designed stent, E2A membrane, and a three-slit pattern created by specific femtosecond laser cutting.

P3393Comparison of intermediate-term vascular response to new-generation biodegradable polymer and durable polymer-based drug-eluting stents: optical coherence tomographic study

Abstract Background Over the last decade, drug-eluting stents (DES) have undergone substantial modifications with thinner struts and more biocompatible durable polymer (DP) or biodegradable polymer (BP). In DP-based DES, after drug elusion has been completed, DP remnants may trigger of local inflammatory vascular reactions and promote delayed healing, leading to accelerated neoatherosclerosis (NA). Thus, BPs have been developed to reduce the above-mentioned risks. Recently, poor strut coverage and in-stent NA are increasingly recognized the cause of late stent failure, but it is unclear whether BPs can reduce the incidence of NA and the poor stent coverage as compared to DPs. Objectives The purpose of this study was to compare the incidence of NA and the stent coverage using optical coherence tomography (OCT) between the DPs and the BPs. Methods Between July 2016 and April 2018, 127 consecutive patients with new-generation DES who underwent 8-month follow up OCT imaging were enrolled. Patients were divided into the two groups: DP group who had the new-generation durable polymer everolimus-eluting and zotarolimus-eluting stents and BP group who had the new-generation biodegradable polymer sirolimus-eluting and everolimus-eluting stents. We compared patient characteristics including hypertension, dyslipidemia and diabetes mellitus and 8-month follow up OCT findings including NA, uncovered struts and malapposed struts between the two groups. Results The DP group comprised 64 patients (50.4%. The incidence of NA, uncovered struts and malapposed struts were similar between the two groups (DPs vs BPs, 1.56% vs 7.94%, P=0.11; 7.80% vs 5.88%, P=0.16 and 2.76% vs 2.01%, P=0.43, respectively) (table). The other parameters were also similar between the two groups. Table 1 DP group (n=64) BP group (n=63) P value Hypertension 44 (68.8%) 50 (79.4%) 0.2251 Dyslipidemia 39 (60.9%) 37 (58.7%) 0.8573 Diabetes mellitus 25 (39.1%) 30 (47.6%) 0.3731 8 month OCT follow up findings Neoatherosclerosis 1 (1.6%) 5 (7.9%) 0.1147 Uncovered struts 7.8% (2.8–20.4) 5.9% (0.7–16.7) 0.1616 Malapposed struts 0.2% (0–2.8) 0% (0–2.8) 0.4392 Conclusions The new-generation DP based-DES may have similar effects on vascular response compared to the new-generation BP-based DES during 8-month follow-up period.

P2800Impact of plaque vulnerability on vascular response after implantation of two types of biodegradable-polymer drug-eluting stent: coronary angioscopic study

Abstract Background Vascular response after drug-eluting stent (DES) implantation depends not only on stent design but also on vulnerability of target coronary lesions. In this study, non-obstructive coronary angioscopy (CAS) revealed vascular response after two types of biodegradable polymer (BP) DES implantation into patients with acute coronary syndrome (ACS) or stable angina pectoris (SAP). Methods Eighteen Nobori BP biolimus-eluting stents (BP-BES) were successfully implanted into 15 patients (9 ACS and 9 SAP lesions). Twenty-three Ultimaster BP sirolimus-eluting stents (BP-SES) were implanted into 16 patients (6 ACS and 17 SAP lesions). At one year after stenting, CAS semi-quantified degree of neointimal stent coverage (NSC) into 4 grades (0, no coverage; 1, thin coverage; 2, thick coverage; 3, embedded in thick neointima and invisible). When NSC through a stent was composed of plural grades, CAS determined dominant, maximum and minimum NSC grades. Heterogeneity index was defined as subtraction of minimum from maximum grade. CAS also semi-quantified degree of yellow plaques (YP) into 3 grades (0, light; 1, dense; 2, glittering yellow). CAS detected presence of in-stent mural thrombi (ISMT). Results At one year after BP-BES implantation: 1) There was no significant difference with regards to dominant NSC between ACS and SAP lesions (1.00±0.50 vs. 0.89±0.60); 2) Heterogeneity index was greater in ACS than in SAP (1.22±0.44 vs. 0.67±0.50, P=0.02); 3) YP grade was greater in ACS than in SAP (1.89±0.33 vs. 1.00±1.00, P=0.02); and 4) We found one ISMT in ACS lesions and two ISMT in SAP lesions. At one year after BP-SES implantation: 1) There was neither significant difference between ACS and SAP lesions with regards to dominant NSC (1.67±1.21 vs. 1.53±1.01), with regards to heterogeneity index (0.50±0.55 vs. 0.35±0.49), nor with regards to YP grade (1.33±1.51 vs. 0.88±0.99); and 2) We found ISMT neither in ACS nor in SAP lesions. Conclusions For BP-SES implantation, vascular response at ACS lesions was similar to SAP lesions. Even one year after BP-BES implantation, however, plaque vulnerability appeared to remain in ACS lesions.

Single- versus multiple-stage catheter-directed thrombolysis for acute iliofemoral deep venous thrombosis does not have an impact on iliac vein stent length or patency rates

BackgroundIncomplete venous thrombolysis and residual nonstented iliac vein disease are known predictors of recurrent deep venous thrombosis (DVT). Controversy exists as to whether the number of thrombolysis sessions affects total stent treatment length or stent patency. The goal of this study was to evaluate the outcomes of patients who underwent single vs multiple catheter-directed lysis sessions with regard to stent extent and patency. MethodsConsecutive patients who underwent thrombolysis and stenting for acute iliofemoral DVT between 2007 and 2018 were identified and divided into two groups on the basis of the number of treatments performed (one vs multiple sessions). Operative notes and venograms were reviewed to determine the number of lytic sessions performed and stent information, including size, location, total number, and length treated. End points included total stent length, 30-day and long-term patency, and post-thrombotic syndrome (Villalta score ≥5). The χ2 comparisons, logistic regression, and survival analysis were used to determine outcomes. ResultsThere were 79 patients who underwent lysis and stenting (6 bilateral interventions; mean age, 45.9 ± 17 years; 48 female). Ten patients (12 limbs) underwent single-stage treatment with pharmacomechanical thrombolysis, and the remaining 69 (73 limbs) had two to four operating room sessions combining pharmacomechanical and catheter-directed thrombolysis. Patients who underwent a single-stage procedure were older and more likely to have a malignant disease. These patients received less tissue plasminogen activator compared with the multiple-stage group (17.2 ± 2.2 mg vs 27.6 ± 11.6 mg; P = .008). Average stent length was 8.8 ± 5.2 cm for the single-stage group vs 9.2 ± 4.6 cm for the multiple-stage group (P = .764). Patients who underwent a single-stage procedure had no difference in average length of stay from that of patients who underwent multiple sessions (8.5 days vs 5.9 days; P = .269). The overall 30-day rethrombosis rate was 7.3%. Two-year patency was 72.2% and 74.7% for the single and multiple stages, respectively (P = .909). The major predictors for loss of primary patency were previous DVT (hazard ratio [HR], 5.99; P = .020) and incomplete lysis (HR, 5.39; P = .014) but not number of procedures (HR, 0.957; P = .966). The overall post-thrombotic syndrome rate was 28.4% at 5 years and was also not associated with the number of treatment sessions. ConclusionsSingle- vs multiple-stage thrombolysis for DVT is not associated with a difference in extent of stent coverage. Patency rates remain high for iliac stenting irrespective of the number of lytic sessions, provided lysis is complete and the diseased segments are appropriately stented.

Study on the Patency of the Contralateral Iliac Vein After Stenting Across the Iliocaval Confluence With an Experimental In Vivo Model.

Stenting is the preferred treatment for iliac vein lesions. For the treatment of occlusions in the junction of the iliac vein and the inferior vena cava (IVC), the stent needs to be positioned in the IVC to cover the lesion. However, the pathological changes in the contralateral iliac vein due to stent coverage on its ostium remain unclear. We observed the patency of the contralateral iliac vein via animal experiments. The stents were placed in the left iliac vein and extended into the IVC in 8 beagle dogs. Doppler ultrasonography, angiography, and histopathological examination were used to assess the patency and histopathological changes in the contralateral iliac vein. Angiography showed patency of the contralateral iliac vein and no sign of thrombosis or stenosis. Twelve months after stenting, Doppler ultrasonography showed a stenotic change in the ostium of the contralateral iliac vein. The histopathological examination showed that the stent strut at the ostium of the contralateral iliac vein was mostly covered by the intima, and the cross-sectional stenosis rate was greater than 60%. The coverage of the iliac vein stent on the ostium of the contralateral iliac vein does not cause complete occlusion of the contralateral vein but can cause significant stenosis at the ostium of the contralateral iliac vein, which is considered to be a potential risk factor for thrombosis.