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AIMS We evaluated the first in-human performance of a novel hybrid imaging catheter that permits simultaneous and co-registered acquisition of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) images. METHODS AND RESULTS A total of 17 patients undergoing planned percutaneous coronary intervention (PCI) were imaged between August 2018 and August 2019. Eleven patients with both pre- and post-PCI IVUS and OCT images were included in the offline image analysis. IVUS and OCT images were analyzed separately then together with co-registered images for pre-stent findings, and only separately for post-stent findings. A total of 926 frames were analyzed (218 pre-PCI, 708 post-PCI). There was substantial agreement to detect calcific plaque between co-registered IVUS-OCT and standalone IVUS (Kappa 0.72 [0.65-0.79]) and standalone OCT (Kappa 0.75 [0.68-0.81]) while standalone imaging modalities showed lower agreement to detect lipidic and fibrotic plaques compared with co-registered IVUS-OCT. There were more frames with stent underexpansion on IVUS than OCT [72 (28.7%) vs. 58 (23.1%), respectively, p = 0.039]. Detection rates of incomplete stent apposition (present on 20 OCT frames vs. 2 IVUS frames, p

A longtime aspiration of interventional cardiologists remains to improve the long-term impact of stent permanence in coronaries to restore original vessel patency and physiological endothelium response. Bioresorbable vascular scaffolds were considered revolutionary in coronary devices, but several trials were disappointing; thus, the challenge in this field remains. DESolve is a novolimus-eluting poly-L-lactide-based polymer scaffold that dissolves through a bio-reabsorption mechanism, vanishing completely in 2 years. Its ability to supply the necessary radial strength to support the vessel for the critical early months after delivery is an important feature showing a unique self-correction property, which reduces incomplete stent apposition. Overexpansion has a good, safe margin with DESolve. This review aims to provide an overview of this controversial topic.

BACKGROUND High-resolution intravascular ultrasound (HR-IVUS) is the most recently developed IVUS technology, which allows the detailed assessment of intravascular structures. The aim of this study was to evaluate the diagnostic performance of HR-IVUS in the detection of abnormal post-stent findings.Methods and Results:Patients with acute coronary syndrome underwent both HR-IVUS and optical coherence tomography (OCT) for post-stent evaluations. Quantitative measurements for stented segments and qualitative assessments for abnormal post-stent findings (stent edge dissection, intrastent tissue protrusion, and incomplete stent apposition [ISA]) were performed. Forty-seven patients underwent both HR-IVUS and OCT after stent implantation. HR-IVUS identified a larger minimal lumen area and a larger minimal lumen diameter than OCT (6.66±1.98 mm2vs. 5.61±1.79 mm2and 2.87±0.42 mm vs. 2.63±0.43 mm, respectively; both P

The healing process of acute incomplete stent apposition (ISA) in the early phase after stent implantation has not been well understood. We evaluated the temporal changes of ISA during the early phase after everolimus-eluting stent (EES) implantation using serial optical coherence tomography (OCT) analyses. Serial OCT examinations were performed immediately post-stenting and 2-week and 4-month after EES implantation for patients with ST-segment elevation myocardial infarction. At the most proximal cross-section of the implanted stent, the prevalence of ISA and maximum ISA distance were serially evaluated. In 45 patients with ST-segment elevation myocardial infarction, serial OCT analyses at 2-week and 4-month were performed. The prevalence of ISA gradually decreased over time, being 53.3% at baseline, 37.8% at 2-week follow-up, and 11.1% at 4-month follow-up (P 0.001). The maximum ISA distance also decreased over time (P 0.001). A receiver-operating curve analysis found that the optimal cut-off values of the baseline ISA distance for predicting persistent ISA at 2-week follow-up and 4-month follow-up were 140 µm and 215 µm, respectively. The baseline ISA distance was closely associated with the healing of ISA in the early phase after EES implantation. Maintaining the minimum ISA distance at post-stenting facilitates early phase healing of acute ISA.

Background Incomplete stent apposition (ISA) can be divided into acute and late forms. Late ISA may be due to persistent ISA or late-acquired ISA (LAISA). This study evaluated the natural course of ISA after bioresorbable vascular scaffold (BRS) implantation using optical coherence tomography (OCT). Methods Thirty-two patients (45 BRS) were assessed immediately after BRS implantation and 1 year thereafter using OCT. Acute ISA identified after BRS implantation but absent at follow-up was defined as resolved; otherwise, it was considered persistent. LAISA was defined as newly developed ISA that was identified at follow-up despite complete apposition immediately after BRS implantation. Intra-BRS fibrin-like material (IBF) was identified as an irregular intraluminal mass. ISA percentage was expressed as follows: (number of ISA/total number of BRS struts) × 100. Results Among 45 BRS and 15,894 analyzed BRS struts, 34 and 882 had acute ISA post-procedure, respectively. At follow-up, 92 of 15,364 analyzed struts exhibited late ISA (64 persistent ISA and 28 LAISA). In 15 of 28 struts with LAISA, LAISA occurred at the sites adjacent to post-interventional dissection. Uncovered struts were more frequently observed in late ISA compared to apposed struts (3.7 ± 4.8 vs. 0.58 ± 2.2%, p = 0.09). IBF was significantly more common in BRS with late ISA (62.5 vs. 8.1%, p = 0.02). Receiver-operating characteristic curve analysis identified a cut-off value of 280 μm for acute ISA distance predicting persistent ISA. Conclusion Resolution of acute ISA after BRS is common. The occurrence of LAISA may be infrequent and may be a nidus of stent thrombosis.

Background There is a lingering controversy in the current literature about the impact of late incomplete stent apposition (LISA) on clinical outcomes, especially stent thrombosis (ST). Therefore, we aimed to synthesize the available evidence evaluating the association between LISA and adverse clinical outcomes. Methods We systematically searched electronic databases for studies reporting clinical outcomes in patients with and without LISA. Relevant study characteristics and clinical outcomes were extracted. Incidence rate ratios (IRR) and 95% Confidence Interval (CI) were computed. Sensitivity analyses were done. Results Sixteen studies with 4,946 patients; 666 patients with 20,035 patient-months follow up with LISA and 4,280 patients with 121,855 patient-months follow up without LISA were included. The estimated prevalence of LISA at follow up was 16% (95% CI 12–20%). The incidences of late/very late ST (IRR = 4.81, 95% CI 2.68–8.62) and myocardial infarction (MI) (IRR = 3.09, 95% CI 1.72–5.55) were significantly higher in the LISA group compared to patients without LISA. Subset analysis of studies reporting Academic Research Consortium definitive/probable ST (IRR = 4.98; 95% CI 2.51–9.89) and acquired LISA (IRR = 3.67, 95% CI 1.5–9.0) similarly showed increased risk of late/very late ST. The results of sensitivity analyses were consistent. There was no difference in cardiac death and target lesion revascularization. Conclusion The presence of LISA at a follow up of 6–18 months after stent implantation is associated with a higher risk of late/very late ST and MI. Additional studies are required to establish a cause and effect, and inform the management strategy. © 2017 Wiley Periodicals, Inc.

Key Clinical Message If we had a case with angiographic peri‐stent contrast staining(PSS)s after the first‐generation sirolimus‐eluting stent, we need a further observation using coronary imaging modalities to evaluate the risk of very late stent thrombosis due to PSSs and to continue or to resume the dual antiplatelet therapy if necessary.

Incomplete stent apposition (ISA) is related to stent thrombosis, which is a serious adverse event. We aim to assess the time-course of ISA after 2nd generation everolimus-eluting stent (EES) implantation.In HEAL-EES study, we enrolled 36 patients who underwent percutaneous coronary intervention (PCI) with EES. OCT imaging was performed at baseline and follow-up. Patients were randomized 1:1:1 into 3 groups according to the time in which follow-up was performed: group A (6-month), group B (9-month), and group C (12-month). In this subanalysis, patients who had ISA segments at baseline and/or follow-up OCT were analyzed.At baseline, among 41 lesions in 36 patients, 20 lesions in 18 patients had ISA segments and were analyzed. At baseline, there were 3.0% ISA struts in group A (n=8), 2.8% in group B (n=4), and 4.5% in group C (n=8). At follow-up, ISA struts were present in 0.09%, 0.16% and 0.64%; respectively in groups A, B, and C. At follow-up, there was a significant decrease in the frequency of ISA: group A 3.0% vs. 0.09% (p0.001), group B 2.8% vs. 0.16% (p0.001), and group C 4.5% vs. 0.64% (p0.001). In group A, there was one late acquired ISA at follow-up.In patients undergoing 2nd generation EES implantation, area of acute ISA assessed by OCT, was almost resolved at 6-month follow-up.

Background Previous optical coherence tomography (OCT) study demonstrated that the incomplete stent apposition (ISA) distance Methods From the population of the ACS-OCT trial, we identified a total of 45 patients who successfully underwent serial OCT examinations at post-stenting, 2-week follow-up, and 4-month follow-up. The presence of ISA was assessed in the OCT images, and ISA distance was measured within the stented segment. The target site for OCT analysis was the cross-section at the proximal edge of implanted stent. Serial OCT images at post-stenting, 2-week follow-up and 4-month follow-up were reviewed side by side on the screen, and maximum ISA distance and cross-sectional ISA area were measured. Results Incomplete stent apposition was observed in all EES at post-stenting, and it was persistent in 37.8% at 2-week follow-up and 11.1% at 4-month follow-up. Maximum ISA distance was significantly decreased over time (post-stenting, 144±150mm; 2-week follow-up, 88±146mm; 4-month follow-up, 34±111mm). Receiver-operating curve analysis identified that the best cut-off value of OCT-estimated ISA distance at post-stenting for predicting persistent ISA at 2-week follow-up and 4-month follow-up was >140μm and >215μm, respectively. ROC curve analysis Conclusion ISA distance at post-stenting is an useful predictor for the resolution of ISA in the early phase after EES implantation.

The purpose of this study was to clarify a cut-off value for acute incomplete stent apposition (ISA) volume and maximum-depth to predict ISA resolution at 1- and 3-month follow-up in patients treated with cobalt–chromium everolimus-eluting stents. In total, 95 cases and 103 stents were registered in the MECHANISM-Elective sub-study. Acute ISA-volume was measured by the trapezoid rule. ISA resolution of cut-off value at 1- and 3-month was estimated by ISA-volume and maximum-depth using receiver operatorating characteristic curve analysis. The total number of analysed acute ISAs was 202 in the 1-month group and 225 in the 3-month group. A total of 123 ISAs at 1-month and a total of 169 ISAs at 3-month had been resolved. The cut-off value of ISA resolution by ISA-volume was 0.169 mm3 at 1-month (AUC: 0.725, sensitivity: 72.2%, specificity: 61.0%) and 0.295 mm3 at 3-month (AUC: 0.757, sensitivity: 75.0%, specificity: 60.4%). The cut-off value of ISA resolution by ISA maximum-depth demonstrated was 0.285 mm at 1-month (area under curve (AUC): 0.789, sensitivity: 70.9%, specificity: 69.9%) and 0.305 mm at 3-month (AUC: 0.663, sensitivity: 60.7%, specificity: 66.9%). Incidence of ISA resolution was significantly lower in combination with cut-off values of ISA-volume and maximum-depth (33%, p

BackgroundEnterprise VRD, a stent frequently used to assist coil embolization of cerebral aneurysms, has been upgraded to reduce the risk of incomplete stent apposition (ISA), a known risk factor for thromboembolic complications.ObjectiveTo compare the performances of Enterprise VRD and Enterprise VRD2 in curved vessels, and to investigate a deployment method that takes advantage of the features of Enterprise VRD2 to achieve better vessel wall apposition.Materials and methodsA silicone vascular model connected to a temperature-adjustable perfusion circuit was used. First, Enterprise VRD and Enterprise VRD2 were deployed under fluoroscopy and then ISA was evaluated as the stent cross-sectional area ratio at the curved segment of the vessel. For the measurements, each stent was deployed in vessels with different angles of curvature. Second, the incidence of ISA after insertion of Enterprise VRD2 by the ‘pushing over outer curve technique’, in which stents are deployed along the outer curve of vessels with continuous wire advancement, was compared with ‘Heller's push and pull technique’.ResultsFor all stents, the cross-sectional area ratio decreased with acute curvature of the vessel. Comparisons of the two stents showed that Enterprise VRD2 was better than Enterprise VRD in maintaining a greater cross-sectional area ratio in curved vessels. In addition, kinking with an acute curvature was also minimized with Enterprise VRD2. Furthermore, ISA was reduced using our technique with Enterprise VRD2.ConclusionsEnterprise VRD2 is superior to Enterprise VRD in reducing ISA in curved vessels and can alter ISA according to the deployment technique used.

AIMS Previous studies have associated issues such as incomplete stent apposition with delayed healing and adverse events (stent thrombosis). The aim of this study was to evaluate the impact of strut apposition and stent type on the progression of stent strut coverage. METHODS AND RESULTS We evaluated in vivo in porcine models the follow-up response and coverage characteristics of well-apposed and malapposed segments of drug-eluting stents (DES) (CYPHER, PROMUS Element and Orsiro) and the Absorb bioresorbable vascular scaffold (BVS) by optical coherence tomography (OCT) sequentially, at baseline, and at one week and four weeks of follow-up. Supporting results were provided by histological analysis performed at four-week follow-up and computer simulation describing the shear characteristics around apposed and non-apposed struts. A total of 325 cross-sections containing 3,166 struts were analysed. The extent of malapposition decreased over time as a result of neointimal healing (from 7.1% at baseline to 0% at four weeks; p=0.03). At one week, 13.6% of struts in well-apposed segments were still uncovered versus 19.2% of struts in malapposed cross-sections and 77.8% of NASB struts (p

Cardiac computed tomography (CT) is a rapidly evolving imaging modality that has developed quickly over the last decade, to establish itself as a robust non-invasive method to assess coronary artery disease. Qualitative and quantitative assessment of atherosclerotic coronary stenosis with cardiac CT has been favorably compared with invasive coronary angiography and intravascular ultrasound (IVUS) and importantly may help improve risk stratification and predict prognosis. Cardiac CT can visualize coronary artery bypass grafts with high diagnostic accuracy, with the evaluation of stents improving all the time. Importantly for the interventional cardiologist, it has evolved into a crucial tool assisting in the planning of both coronary and structural heart interventions, with transcatheter aortic valve implantation the most successful example. With its resemblance to IVUS in the capability to assess both the lumen and vessel wall, cardiac CT provides additional information on the composition of the lesion and reference segments which might allow accurate selection of devices, potentially leading to complete lesion coverage, less incomplete stent apposition, and larger postprocedural diameters. An understanding of the uses of CT and keeping up to date with evolving CT technology is critical for the interventional cardiologist as the use of CT continues to evolve and establish itself as an everyday adjunct to cardiac intervention. Answer questions and earn CME: https://wileyhealthlearning.com/Activity2/4193301/Activity.aspx

Aims: Fully bioresorbable Absorb poly-L-lactic-acid (PLLA) scaffolds (Abbott Vascular, Santa Clara, CA, USA) are a novel approach for the treatment of coronary narrowing. Due to the translucency of the material (PLLA), the optical coherence tomography (OCT) measurement methods used in the ABSORB trials were unique but not applicable for permanent metallic stents. When the Absorb scaffold and metallic stents are compared in the context of randomised trials, it is challenging to compare the two devices using the conventional methods. The primary purpose of this report is to explain the biases in conventional methodologies applied for metallic stents and for PLLA scaffolds at baseline and follow-up, and to propose a new standard methodology that enables us to compare two different devices using an almost identical and methodological language. Methods and results: A consensus amongst multiple core labs and expert researchers of OCT was reached on a new standard OCT measurement methodology that enables us to compare these two different devices. In brief, the proposed OCT methods are summarised as follows. 1) Both endoluminal and abluminal scaffold/stent contours should be traced. 2) Consistently, endoluminal and abluminal incomplete stent apposition areas should be measured. 3) The area occupied by scaffold/stent struts should be quantified directly or virtually. 4) The strut area should be systematically excluded from the flow area as well as the neointimal area. 5) Additional information on the degree of embedment could be reported using the interpolated lumen contour. Interobserver variability of the proposed method was excellent (intraclass correlation 0.89-100). Conclusions: A standardised OCT measurement methodology is proposed. This should be implemented in ongoing and future trials comparing the Absorb scaffolds and metallic stents.

The current meta-analysis evaluates the relationship of late incomplete stent apposition (LISA) observed either by IVUS or OCT 6-18 months after PCI and long-term outcomes, particularly in regard to stent thrombosis (ST) and has demonstrated a small but significant increase in ST with LISA. The results of the current study do not apply to acute stent malapposition whose relevance to adverse outcomes is uncertain based on current evidence and a malapposition classification based on presence, length, and severity of malapposed struts. A classification of stent malapposition based on cause of malapposition is proposed as a method to determine prognostic importance of acute incomplete stent apposition.

International audience; Endovascular repair of abdominal aortic aneurysms faces some adverse outcomes, such as kinks or endoleaks related to incomplete stent apposition, which are difficult to predict and which restrain its use although it is less invasive than open surgery. Finite element simulations could help to predict and anticipate possible complications biomechanically induced, thus enhancing practitioners' stent-graft sizing and surgery planning, and giving indications on patient eligibility to endovascular repair. The purpose of this work is therefore to develop a new numerical methodology to predict stent-graft final deployed shapes after surgery. The simulation process was applied on three clinical cases, using preoperative scans to generate patient-specific vessel models. The marketed devices deployed during the surgery, consisting of a main body and one or more iliac limbs or extensions, were modeled and their deployment inside the corresponding patient aneurysm was simulated. The numerical results were compared to the actual deployed geometry of the stent-grafts after surgery that was extracted from postoperative scans. We observed relevant matching between simulated and actual deployed stent-graft geometries, especially for proximal and distal stents outside the aneurysm sac which are particularly important for practitioners. Stent locations along the vessel centerlines in the three simulations were always within a few millimeters to actual stents locations. This good agreement between numerical results and clinical cases makes finite element simulation very promising for preoperative planning of endovascular repair.

Incomplete stent apposition and uncovered struts are associated with a higher risk of stent thrombosis. No data exist on the process of neointimal coverage and late apposition status of the bioresorbable vascular scaffold (BVS) when implanted in the highly thrombogenic setting of ST-segment elevation acute myocardial infarction (STEMI). The aim of this study was to assess the serial changes in strut apposition and early neointimal coverage of the BVS using optical coherence tomography (OCT) in selected patients enrolled in the PRAGUE-19 study. Intracoronary OCT was performed in 50 patients at the end of primary percutaneous coronary intervention for acute STEMI. Repeated OCT of the implanted BVS was performed in 10 patients. Scaffold area, scaffold mean diameter and incomplete strut apposition (ISA) were compared between baseline and control OCT. Furthermore, strut neointimal coverage was assessed during the control OCT. Mean scaffold area and diameter did not change between the baseline and control OCT (8.59 vs. 9.06 mm(2); p = 0.129 and 3.31 vs. 3.37 mm; p = 0.202, respectively). Differences were observed in ISA between the baseline and control OCT (0.63 vs. 1.47 %; p 0.05). We observed 83.1 % covered struts in eight patients in whom the control OCT was performed 4-6 weeks after BVS implantation, and 100 % covered struts in two patients 6 months after BVS implantation. Persistent strut apposition and early neointimal coverage were observed after biodegradable vascular scaffold implantation in patients with acute ST-segment elevation myocardial infarction.

Bioresorbable vascular scaffolds (BRSs) have recently reenergized the field of coronary intervention; they support transient drug delivery and vessel patency and then gradually tend to complete resorption. OCT has played a major role in the development of BRS technology by providing more precise and detailed morphologic information (compared to IVUS) as a result of its higher resolution. While the clinical outcome data from the landmark BRS trials are promising, there is a paucity of data on BRS implantation in unselected patient population in “real world” clinical practice, including in-stent restenosis, bifurcation, and severely calcified lesions. Abnormal coronary dilatation at the site of DES implantation demonstrating contrast staining outside the stent struts, peri-stent contrast staining (PSS), have been shown to be associated with target-lesion revascularization and very late stent thrombosis. OCT can differentiate between two main underlying causes of PSS, incomplete stent apposition and multiple interstrut hollows or cavities between well apposed stent struts. Intraluminal filling defects are occasionally observed on coronary angiography, and thrombosis has often been used as a default diagnosis; however, there are many different causes responsible for the phenomenon including calcification, dissection, plaque rupture, and artifacts. OCT allows accurate characterization angiographic filling defects and provides important information for treatment optimization.

The coronary guidewire re-crossing position before the final kissing balloon post-dilation is important to reduce the incidence of incomplete stent apposition in bifurcation lesions. Angiography and intravascular ultrasonography are unreliable at detecting the site of wire re-crossing. The high resolution of optical coherence tomography (OCT) offers the advantage of precise assessment of construction in bifurcation. However, the OCT technique still has some limitations, including the requirement for additional contrast and expense. We present two cases where the ClearStent Live system technique was used to estimate the wire location, which was verified by using OCT. In conclusion, ClearStent can be used with or to replace the intracoronary imaging technique in selected cases.

Bifurcation angle (BA) influences incomplete stent apposition (ISA) at side branch ostium after kissing balloon inflation (KBI). Although BA can be measured by various methods, this study investigated whether 3-dimensional (3D)-optical coherence tomography (OCT) bifurcation types could predict ISA

Background— Although significant undersizing often results in incomplete stent apposition or underexpansion, the possible impact of oversized stent implantation on arterial wall injury has not been systematically investigated with drug-eluting stents. The aim of this study was to investigate the impact of stent oversizing on acute and long-term outcomes after drug-eluting stents implantation in de novo coronary lesions. Methods and Results— Serial (baseline and 6–12 months) coronary angiography and intravascular ultrasound were performed in 2931 lesions treated with drug-eluting stents (355 sirolimus, 846 paclitaxel, 1387 zotarolimus, and 343 everolimus). The percentage of stent oversizing to angiographic reference vessel diameter (RVD) was calculated as (nominal stent diameter–RVD)/RVD×100 (%). Clinical outcomes, including target lesion revascularization and stent thrombosis, were followed for 1 year. Overall, smaller preintervention RVD was associated with higher percentage of stent oversizing ( P P =0.002) but achieved greater stent expansion ( P P P =0.002) and target lesion revascularization rates ( P =0.007) were found in favor of larger vessel size and oversized stents. Stent thrombosis was observed the most in small RVD with low percentage of stent oversizing group among the subgroups ( P =0.040). Conclusions— The positive impact of stent oversizing was documented on procedural and clinical outcomes. In particular, small vessels treated with smaller stents were associated with greater adverse events, suggesting that aggressive selection of larger stents, with appropriate attention to edge effects, may optimize long-term outcomes, even in drug-eluting stents implantation.

BACKGROUND The role of culprit plaque and related atherothrombotic components on incomplete stent apposition (ISA) occurrence after primary percutaneous coronary intervention (p-PCI) is unknown. METHODS AND RESULTS ST-segment elevation myocardial infarction (STEMI) patients undergoing p-PCI with an everolimus-eluting stent were prospectively investigated with optical coherence tomography (OCT) of the infarct-related artery before, after stenting and at 9 months. OCT data, aspirated thrombus and serum inflammatory biomarkers were analyzed. 114 patients with 114 lesions were evaluated. Acute ISA occurred in 82 lesions (71.9%), preferentially in larger vessels with a median area of 0.2 mm(2). The presence of thrombus before stent implantation (odds ratio (OR) 5.5, 95% confidence interval (CI) [1.1-26.9], P=0.04) and the lipid content in the target segment (OR 1.3, 95% CI [1.0-1.5], P=0.04) independently predicted acute ISA. At 9-month follow-up, ISA persisted in 46 lesions (56.1%). The volume of acute ISA significantly predicted persistent ISA (OR 1.3, 95% CI [1.1-1.5], P=0.01). Late-acquired ISA occurred in 39 lesions (34.2%) with a median area of 0.3 mm(2). Red/mixed thrombus before stent implantation (OR 3.7, 95% CI [1.0-13.3], P=0.05) and length of the underlying ruptured plaque (OR 1.7, 95% CI [1.1-2.8] P=0.02) were independently associated with late-acquired ISA. CONCLUSIONS In STEMI patients, culprit plaque and atherothrombotic components of the infarct-related artery significantly contribute to the onset of acute and late ISA. ISA persistence at follow-up depends on the initial volume of acute ISA.

According to data from stent-enhanced three-dimensional optical coherence tomography, incomplete stent apposition after side branch dilation in coronary bifurcation stenting can be reduced by the free carina type (no links bridged from a carina) and by distal cell rewiring. This is the first report to describe a bent stent technique that was devised to achieve the free carina type (no links bridged from a carina), as a favorable jailing configuration.

A previous optical coherence tomography (OCT) study showed that incomplete stent apposition (ISA) of drug eluting stents is a major risk factor for stent thrombosis. The cobalt-chromium everolimus-eluting stent (CoCr- EES) incorporating a highly biocompatible stent is used in combination with short

Persistent or late acquired incomplete stent apposition (ISA) may be associated with late or very late stent thrombosis following drug-eluting stent implantation. Presence of calcium at the target lesion may increase the risk of ISA even after rotational atherectomy (RA) followed by stenting with

Quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercial self-expandable braided stents with 3 commonly used end shapes, to evaluate the influence of different end shapes of stent on the biomechanical interaction between stent and oesophagus. The end shape has no influence on the equivalent stress, but has a great influence on the contact stress in the narrowest zone of the oesophagus-neoplasm system. However, the end shapes have significant effect on the equivalent stress and the contact stress in the healthy area of the oesophagus in contact with the stent ends. The results show that the maximum equivalent stress of the oesophagus occurs in the zone contact with the cup-shaped end and the maximum contact stress occurs in the zone contact with the edge of the trumpet-shaped stent end. Moreover, the stent apposition is almost not affected by the end shapes. Although small zones with an incomplete stent apposition appear in the transition zones of spherical-cup-shaped stent, such occurrence might not contribute to stent malapposition or stent migration. Therefore, these stents with 3 types of end shapes all have good stent apposition. Finally, the numerical simulation results can be used to assess the mechanical performance of stents with different end shapes, the effectiveness of stent expansion therapy, and the possibility of complications after stent implantation.

Several clinical and pathological studies have suggested an association between incomplete stent apposition (ISA) and delayed neointimal healing and adverse events (stent thrombosis).The aim of this study was to evaluate the impact of strut apposition and stent design on progression of stent strut