Thin-strut Stent Research Articles

An investigation of PLLA hybrid stent design to overcome thick strut problems

Biodegradable polymer-based stents simultaneously provide scaffolding, drug release, and biodegradation to eliminate chronic inflammation. The most important factors hindering the wide use of these stents are thick struts, low radial strength, and large footprints formed on the inner wall of the artery as a result of stent expansion. Negative Poisson’s Ratio (NPR), also known as the Auxetic design, has shown great potential to provide radial strength with less strut thickness. However, a detailed mechanical evaluation proving improvement in stent performance parameters is not available in the literature. In this study, the performance parameters of two stent designs based on the Auxetic geometry with PLLA were analyzed under in-vivo conditions using an in-silico model consisting of the artery, crimper, and expander FE model. For this purpose, one design utilizes Auxetic unit cell, which is already available in the literature, while the other uses a newly proposed Hybrid design combining Auxetic and Chevron type geometries. Additionally, a specially heated coaxial balloon-catheter system was considered as a deployment tool between glass transition and body temperature, and carried out for thin-strut stent simulations. The Hybrid design is shown to resolve the foreshortening problem of Auxetic design and collapse pressure of commercial PLLA stents. In this present study validates the potential of Hybrid design to overcome problems for polymer-based biodegradable stents.

Additive Manufacturing of Biodegradable Molybdenum - From Powder to Vascular Stent.

Magnesium, iron, and zinc-based biodegradable metals are widely recognized as promising candidate materials for the next generation of bioresorbable stent (BVS). However, none of those metal BVSs are perfect at this stage. Here, a brand-new BVS based on a novel biodegradable metal (Molybdenum, Mo) through additive manufacturing is developed. Nearly full-dense and crack-free thin-wall Mo is directly manufactured through selective laser melting (SLM) with fine Mo powder. Systemic analyses considering the forming quality, wall-thickness, microstructure, mechanical properties, and in vitro degradation behaviors are performed. Then, Mo-based thin-strut (≤ 100µm) stents are successfully obtained through an optimized single-track laser melting route. The SLMed thin-wall Mo owns comparable strength to its Mg and Zn based counterparts (as-drawn), while, it exhibits remarkable biocompatibility in vitro. Vessel related cells are well adhered and spread on SLMed Mo, and it exhibits a low risk of hemolysis and thrombus. The SLMed stent is compatible to vessel tissues in rat abdominal aorta, and it can provide sufficient support in an animal model as an extravascular stent. This work possibly opens a new era of manufacturing Mo-based stents through additive manufacturing.

Enhancing thromboresistance of neurovascular nickel-titanium devices with responsive heparin hydrogel coatings

BackgroundNeurointerventional devices, particularly laser-cut thin-strut stents made of self-expanding nickel-titanium alloy, are increasingly utilized for endovascular applications in intracranial arteries and dural venous sinuses. Preventing thrombosis and stroke necessitates systemic...

Ultrathin-strut versus thin-strut stent healing and outcomes in preclinical and clinical subjects.

Compared with thin-strut durable-polymer drug-eluting stents (DP-DES), ultrathin-strut biodegradable-polymer sirolimus-eluting stents (BP-SES) improve stent-related clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). Reduced stent strut thickness is hypothesised to underlie these benefits, but this conjecture remains unproven. We aimed to assess the impact of strut thickness on stent healing and clinical outcomes between ultrathin-strut and thin-strut BP-SES. First, we performed a preclinical study of 8 rabbits implanted with non-overlapping thin-strut (diameter/thickness 3.5 mm/80 μm) and ultrathin-strut (diameter/thickness 3.0 mm/60 μm) BP-SES in the infrarenal aorta. On day 7, the rabbits underwent intravascular near-infrared fluorescence optical coherence tomography (NIRF-OCT) molecular-structural imaging of fibrin deposition and stent tissue coverage, followed by histopathological analysis. Second, we conducted an individual data pooled analysis of patients enrolled in the BIOSCIENCE and BIOSTEMI randomised PCI trials treated with ultrathin-strut (n=282) or thin-strut (n=222) BP-SES. The primary endpoint was target lesion failure (TLF) at 1-year follow-up, with a landmark analysis at 30 days. NIRF-OCT image analyses revealed that ultrathin-strut and thin-strut BP-SES exhibited similar stent fibrin deposition (p=0.49) and percentage of uncovered stent struts (p=0.63). Histopathological assessments corroÂborated these findings. In 504 pooled randomised trial patients, TLF rates were similar for those treated with ultrathin-strut or thin-strut BP-SES at 30-day (2.5% vs 1.8%; p=0.62) and 1-year follow-up (4.3% vs 4.7%; p=0.88). Ultrathin-strut and thin-strut BP-SES demonstrate similar early arterial healing profiles and 30-day and 1-year clinical outcomes.

Abstract 14778: Combined Shear Stress-Molecular Imaging for the Evaluation of Early Arterial Healing Responses Following Implantation of Bioresorbable Scaffold With Different Strut Thickness

Introduction and Hypothesis: Arterial healing following stent implantation involves a series of biological reactions such as thrombosis, inflammation, neointimal regeneration. Clinical evidences have shown favorable arterial healing after thin-strut stents, however, there has been a lack of in vivo imaging evidence on how strut thickness affect vascular healing process. We evaluated local endothelial shear stress (ESS) and healing response of a thin-strut bioresorbable scaffold (BRS, 100μm) compared to first-generation 157μm-thickness ABSORB. Methods and Results: BRS and ABSORB were simultaneously implanted in left coronary arteries of the same pigs (n=7). Detailed scaffolded-artery 3D model was reconstructed based on OCT and angiography. Scaffold-related inflammation response was serially assessed by dual-modal OCT-near-infrared fluorescence (OCT-NIRF) molecular imaging using macrophage-mannose receptor-Cy7 as an inflammation-targeting agent. On ESS analysis, regions with athero-prone low ESS were significantly greater in thick-ABSORB compared to BRS. Dual-modal OCT-NIRF imaging visualized arterial inflammation activity at peri-strut regions in vivo (Figure). Based on coregistered ESS-NIRF data, we found a significant inverse correlation was found between ESS and NIRF activity (p<0.0001), suggesting immune-modulating effect of ESS during early stent healing phase. Arterial inflammation, quantified as target-to-background ratio, was significantly lower in thin-strut BRS than ABSORB at 2 weeks (p<0.01). At week 3, unlike ABSORB with residual peri-strut NIRF signals, inflammation activity dissipated significantly in BRS. Ex vivo confocal fluorescence microscopy (Figure) and immunohistochemical analysis well corroborated the findings in vivo . Conclusions: Thin-strut BRS was associated with less inflammation and rapid resolution of inflammation compared to thicker-strut ABSORB. This study provides in vivo imaging insights into how strut thickness affects early arterial healing and the importance of ESS as an inflammatory modulator. Our comprehensive imaging strategy enabling evaluation of complex interplay between scaffold, ESS, and artery is expected to enhance understanding of stent healing.

Determinants of neointimal strut coverage in bio-degradable polymer coated ultrathin strut stent

Abstract Introduction Incomplete strut coverage (ISC) is the most important morphometric determinant of stent thrombosis. Determinants of ISC have been studied in thick and thin strut stents. Purpose To identify morphometric factors causing ISC in the biodegradable polymer-coated ultra-thin strut drug eluting stent (BP-UTS-DES) that are designed to encourage better strut coverage. Methods Patients undergoing implantation of a 65μm BP-UTS-DES had opportunistic OCT during staged PCI to assess strut coverage at 90 days. Images were analysed offline by experienced operators blinded to patient and procedural data. Neointimal thickness (NIT, μm) was measured as the minimum endoluminal distant between the strut and lumen border. All malapposed struts were considered uncovered. ISC was defined as <100% covered struts in a frame. Stepwise logistic regression using multiple morphometric variables was used to identify independent determinants of ISC including markers of circumferential distribution of neointimal growth (CVS,NUS,RUS), symmetry of stent expansion (SEI, AVS, MAS) in each cross section and the geographical location of the frame along the axis of the stent. Results We analysed 11652 frames of 65 stents (1976 mm) in 46 arteries of 40 patients. All stents were post dilated. 95.6% arteries had >20mm stents, 39.1% were overlapped and 15.2% were chronic total occlusions. Malapposition was seen in 2.6% of all struts and 39.2% of uncovered struts. The proportion of covered struts decreased as indices of circumferential uniformity of distribution of neointimal hyperplasia increased (CVS: r=0.37, p<0.001; RUS: r=0.36, p<0.001; NUS: r=0.52, p<0.001). As uniformity of stent expansion improved (SEI increased) strut coverage and circumferential uniformity of neointimal hyperplasia increased (CVS, NUS and RUS decreased) suggesting that distribution of neointimal growth becomes homogeneous as uniformity of stent expansion improves (Fig. 1). Determinants ISC is shown in Table 1. Conclusion SEI but not AVS or MAS determines ISC. Compared to the distal third of the stent frames in the middle third had lower and the proximal third had high risk of ISC. Funding Acknowledgement Type of funding sources: None.

Performance of Thin-Strut Stents in Non-Left Main Bifurcation Coronary Lesions: A RAIN Subanalysis.

This study assesses the safety and efficacy of thin-strut stents in non-left main (non-LM) bifurcation coronary lesions. Thinner struts of recent drug-eluting stent (DES) devices are associated with improved outcomes, but data about their performance in challenging scenarios are scant. RAIN was a retrospective multicenter registry enrolling patients with coronary bifurcation lesions or left main (LM) disease treated with thin-strut DESs. Target-lesion revascularization (TLR) was the primary endpoint, while major adverse clinical event (MACE) rate, a composite of all-cause death, myocardial infarction (MI), target-vessel revascularization (TVR), TLR, and stent thrombosis (ST), and its single components were the secondary endpoints. Multivariable analysis was performed to identify predictors of TLR. Outcome incidences according to stenting strategy (provisional vs 2-stent technique), use of final kissing balloon (FKB), and intravascular ultrasound/optical coherence tomography optimization were further investigated in prespecified subanalyses. A total of 1803 patients (59% acute coronary syndrome, 41% stable coronary artery disease) with non-LM bifurcations were enrolled. After a median follow-up of 12 months, TLR incidence was 2.5% (2.2% for provisional stenting and 3.5% for 2-stent technique). MACE rate was 9.4% (all-cause death, 4.1%; MI, 3.2%; TVR, 3.7%; definite ST, 1.1%). After multivariable adjustment, postdilation (hazard ratio [HR], 0.32; 95% confidence interval [CI], 0.15-0.71; P<.01) and provisional stenting (HR, 0.62; 95% CI, 0.55-0.89; P=.03) were associated with lower TLR rates. FKB was associated with a lower incidence of TLR in the 2-stent subgroup (P=.03). Intracoronary imaging had no significant impact on the primary endpoint. Thin-strut DES options represent an effective choice in bifurcation lesions. Postdilation and provisional stenting are associated with a reduced risk of TLR. FKB should be recommended in 2-stent techniques.

Meta-analysis comparing sirolimus bioresorbable scaffolds versus everolimus-eluting metallic stents in coronary arterial disease

Abstract Introduction In the acute setting, thin-strut bioresorbable scaffolds (BRS) are noninferior versus the thin-strut drug-eluting stent. Recently, randomized controlled trials (RCTs) with long-term follow-up data have been published. Purpose To evaluate the long-term clinical outcomes of sirolimus BRS versus the benchmark everolimus DES. Methods We reviewed the literature and conducted a meta-analysis of all RCTs comparing sirolimus BRS versus metallic DES stents in patients with CAD. The primary outcomes were all-cause mortality and target vessel failure (TVF). Furthermore, secondary outcomes included cardiac mortality, target vessel myocardial infarction, ischemia-driven target lesion revascularization (TLR), and stent thrombosis (probable and definite). Statistical analysis was conducted using Review Manager 5.4. Two-sided p values of &amp;lt;0.05 were considered as statistical significance. Results A total of 15,930 patients were included with a median-weighted follow up period of 1.68 years. Heterogeneity was low-high across the trials (0–87%). All-cause mortality was insignificant between the two groups (OR 0.95; 95% CI 0.79–1.14; p=0.57) (Figure 1). The rate of TVF showed a trend favoring sirolimus BRS compared to everolimus DES with statistical significance (OR 0.84; 95% CI 0.73–0.98; p=0.02) (Figure 1). Ischemia-driven TLR also statistically favored sirolimus BRS (OR 0.64; 95% CI 0.53–0.77; p&amp;lt;0.ehab724.12301) (Figure 2). Otherwise, all other secondary outcomes favored sirolimus BRS without statistical significance (Figure 2). Conclusion This updated meta-analysis illustrates that in the long term setting sirolimus BRS has significantly decreased rate of TVF and ischemia-driven TLR as compared to everolimus DES. However, there was no statistical difference in the all-cause mortality or cardiac mortality. Funding Acknowledgement Type of funding sources: None.

Polymer-free Biolimus-A9 coated thin strut stents for patients at high bleeding risk 1-year results from the LEADERS FREE III study.

BackgroundIn patients at high bleeding risk (HBR), the LEADERS FREE (LF) trial established the safety and efficacy of a polymer‐free drug coated (Biolimus‐A9) stainless steel stent (SS‐DCS) with 30 days of dual antiplatelet treatment (DAPT). In LEADERS FREE III, we studied a new cobalt‐chromium thin‐strut stent (CoCr‐DCS) in HBR patients.MethodsThe CoCr‐DCS shares all of the design features of the SS‐DCS but has a CoCr stent platform with strut thickness of 84–88 μm. The primary safety endpoint was a composite of cardiac death, myocardial infarction (MI), and definite/probable stent thrombosis. The primary efficacy endpoint was clinically indicated target lesion revascularization. Outcomes were compared to those of LF (non‐inferiority to SS‐DCS for safety and superiority to SS‐BMS for efficacy). Additional propensity‐matched comparisons were performed to account for baseline differences.ResultsWe recruited 401 HBR patients using identical criteria to the LF trial. At 1 year, the primary safety endpoint was reached by 31/401 (8.0%) of patients treated with the CoCr‐DCS versus 35/401 (8.9%) for the propensity‐matched cohort (HR: 0.89, [0.55–1.44], p < 0.001 for non‐inferiority, 0.62 for superiority). The efficacy endpoint was reached by 16/401 (4.2%) of CoCr‐DCS patients versus 41/401 (10.6%) in the propensity‐matched cohort (HR: 0.4 [0.2:0.7]) (p = 0.007 for superiority). There was no statistical difference between CoCr‐DCS and SS‐DCS in terms of efficacy (HR: 1.46 [0.68–3.15], p = 0.33).ConclusionsThe new thin‐strut CoCr‐DCS proved non‐inferior to the SS‐DCS for safety, and superior to the BMS for efficacy in HBR patients treated with 30 days of DAPT.

Stent strut thickness and acute vessel injury during percutaneous coronary interventions: an optical coherence tomography randomized clinical trial.

Compare the degree of acute vascular injury caused by a polymer-free, thin-strut drug-eluting stent (DES) to that caused by a bioresorbable polymer, thick-strut DES using optical coherence tomography (OCT). Fifty patients requiring nonurgent PCI were randomized to receive either a thin or a thick-strut DES. OCT was performed before and after stent implantation. OCT-based injury score (IS) after implantation was numerically higher within thick-strut stents 0.32 vs. 0.23, but the difference was NS (P = 0.61). Edge dissections were present in 36% of the patients without differences between groups. Tissue prolapse (TP) area was larger with thin-strut stents (2.26 vs. 1.83 mm2, P = 0.04). Stent expansion and symmetry index were similar between the two platforms (85% vs. 94%, P = 0.08; and 0.82 vs. 0.80, P = 0.25). No differences were observed in total malapposition area (1.85 mm2 in thin-strut stents vs. 1.47 mm2, P = 0.48). Regarding the influence of plaque-type, IS tended to be higher (non-significant) with thick strut DES in fibrocalcific plaques. Stent malapposition area was smaller in fibrous plaques, especially with thin strut stents (P = 0.03). There was no difference in the extent of OCT-based vessel injury associated with thin and thick-strut DES platforms. TP was larger with the thin strut DES, potentially reflecting a deeper stent embedment in the vessel wall.

Chronic stent recoil in severely calcified coronary artery lesions. A serial optical coherence tomography study.

Chronic second-generation drug-eluting stent recoil in severely calcified coronary lesions has not been studied. We aimed to evaluate chronic stent recoil by optical coherence tomography (OCT) in severely calcified lesions treated with thin strut stents after rotational atherectomy. In 28 lesions (26 patients with 23% on hemodialysis) treated with everolimus-eluting stents after rotational atherectomy, baseline and 8-month follow-up OCT were compared. Stent recoil was defined as >10% decrease in stent area from baseline to follow-up. Overall, there was no change in minimal stent area (6.0 mm2 [5.0, 8.1] to 6.0 mm2 [4.8, 8.6], p = 0.51) from baseline to follow-up, although neointimal hyperplasia measured 16.3 ± 15.8%. Thirty-six percent of lesions showed stent recoil associated with 6 non-nodular calcifications, 1 calcified nodule, and 3 stent deformations. The overall mean calcium angle with attenuation decreased (54° [29-76] to 31° [19-48], p < 0.0001), and calcium without attenuation increased (28° [21-67] to 64° [34-93], p < 0.0001), but primarily at the location of stent recoil. Furthermore, in the stent recoil segments in 10 recoil lesions, the stent circumference decreased primarily at non-calcium segments rather than at calcium with or without attenuation. One lesion with stent recoil and 2 lesions without stent recoil required repeat revascularization. Thin strut stents can chronically recoil in severely calcified lesions, but this rarely causes restenosis.

Accuracy of the PARIS score and PCI complexity to predict ischemic events in patients treated with very thin stents in unprotected left main or coronary bifurcations.

The PARIS risk score (PARIS-rs) and percutaneous coronary intervention complexity (PCI-c) predict clinical and procedural residual ischemic risk following PCI. Their accuracy in patients undergoing unprotected left main (ULM) or bifurcation PCI has not been assessed. The predictive performances of the PARIS-rs (categorized as low, intermediate, and high) and PCI-c (according to guideline-endorsed criteria) were evaluated in 3,002 patients undergoing ULM/bifurcation PCI with very thin strut stents. After 16 (12-22) months, increasing PARIS-rs (8.8% vs. 14.1% vs. 27.4%, p < .001) and PCI-c (15.2% vs. 11%, p = .025) were associated with higher rates of major adverse cardiac events ([MACE], a composite of death, myocardial infarction [MI], and target vessel revascularization), driven by MI/death for PARIS-rs and target lesion revascularization/stent thrombosis for PCI-c (area under the curves for MACE: PARIS-rs 0.60 vs. PCI-c 0.52, p-for-difference < .001). PCI-c accuracy for MACE was higher in low-clinical-risk patients; while PARIS-rs was more accurate in low-procedural-risk patients. ≥12-month dual antiplatelet therapy (DAPT) was associated with a lower MACE rate in high PARIS-rs patients, (adjusted-hazard ratio 0.42 [95% CI: 0.22-0.83], p = .012), with no benefit in low to intermediate PARIS-rs patients. No incremental benefit with longer DAPT was observed in complex PCI. In the setting of ULM/bifurcation PCI, the residual ischemic risk is better predicted by a clinical risk estimator than by PCI complexity, which rather appears to reflect stent/procedure-related events. Careful procedural risk estimation is warranted in patients at low clinical risk, where PCI complexity may substantially contribute to the overall residual ischemic risk.

The effect of intrinsic characteristics on mechanical properties of poly(l-lactic acid) bioresorbable vascular stents

Poly(L-lactic acid) (PLLA) is currently the bioresorbable polymer of choice for vascular stents with its superior biocompatibility and mechanical properties. However, it is still difficult to enhance the radial supporting capacity of PLLA stents without increasing the strut thickness. In this study, the performance of laser-cut thin-strut stents from two groups of PLLA tubes are investigated. We considered two groups of PLLA tubes. Group 1 indicates the longitudinally stretched from original 150-μm-thick tubes, and Group 2 indicates the directly thinned from original 150-μm-thick tubes. Three stages of mechanical tests were conducted in this study, which are defined as tensile tests of dog-bone specimens, radial loading tests of tubes and radial loading tests of stents. The results suggest that Group 2 has higher radial supporting capacity than Group 1 with the same wall thickness. This work serves as a basis for manufacturing thin-strut stents with sufficient radial supporting capacity.

Cost and Mortality Implications of Lower Event Rates After Implantation of an Ultrathin-Strut Coronary Stent Compared With a Thin-Strut Stent Over Four Years

BackgroundThe recent BIOFLOW V trial (ClinicalTrials.gov: NCT02389946) showed that revascularization with an ultrathin strut, bioresorbable polymer sirolimus-eluting stent (BP SES) was associated with lower rates of clinically driven target lesion revascularization (TLR) and target vessel-related myocardial infarction (TVMI) at 24-month follow-up than that with a thin strut, durable polymer everolimus-eluting stent (DP EES). We simulated the impact on cost and mortality. Methods and resultsWe projected the impact of the lower adverse event rates from a U.S. health system perspective over a 48-month horizon with a Markov model using event data from the BIOFLOW V trial and estimates for costs and excess mortality due to adverse events from published sources. All cost estimates were CPI-adjusted to 2018 US$ and future cost discounted by 3%.We estimated that use of BP SES compared to DP EES was associated with cumulative net reductions in medical cost of $2429 per patient over 48 months. Peri-procedural TVMI contributed $124 (5%), TLR in patients without TVMI $810 (33%) and spontaneous TVMI $1496 (62%) of cost. Use of BP SES compared to DP EES was associated with 2603 fewer deaths in one million patients over four years, corresponding to a relative risk reduction of 6%. ConclusionsLower adverse event rates associated with revascularization using BP SES translate into reductions in direct medical cost and mortality. Most of the cost reduction is attributed to reduction in spontaneous TVMI. Given the high volume of coronary procedures, such results are an important consideration for patients, clinicians and payers.

Incidence of Adverse Events at 3 Months Versus at 12 Months After Dual Antiplatelet Therapy Cessation in Patients Treated With Thin Stents With Unprotected Left Main or Coronary Bifurcations

Incidence and predictors of adverse events after dual antiplatelet therapy (DAPT) cessation in patients treated with thin stents (<100 microns) in unprotected left main (ULM) or coronary bifurcation remain undefined. All consecutive patients presenting with a critical lesion of an ULM or involving a main coronary bifurcation who were treated with very thin strut stents were included. MACE (a composite end point of cardiovascular death, myocardial infarction [MI], target lesion revascularization [TLR], and stent thrombosis [ST]) was the primary endpoint, whereas target vessel revascularization (TVR) was the secondary endpoint, with particular attention to type and occurrence of ST and occurrence of ST, CV death, and MI during DAPT or after DAPT discontinuation. All analyses were performed according to length of DAPT dividing the patients in 3 groups: Short DAPT (3-months), intermediate DAPT (3 to 12 months), and long DAPT (12-months). A total of 117 patients were discharged with an indication for DAPT ≤3 months (median 1: 1 to 2.5), 200 for DAPT between 3 and 12 months (median 8: 7 to 10), and 1,958 with 12 months DAPT. After 12.8 months (8 to 20), MACE was significantly higher in the 3-month group compared with 3 to 12 and 12-month groups (9.4% vs 4.0% vs 7.2%, p ≤0.001), mainly driven by MI (4.4% vs 1.5% vs 3%, p ≤0.001) and overall ST (4.3% vs 1.5% vs 1.8%, p ≤0.001). Independent predictors of MACE were low GFR and a 2 stent strategy. Independent predictors of ST were DAPT duration <3 months and the use of a 2-stent strategy. In conclusion, even stents with very thin strut when implanted in real-life ULM or coronary bifurcation patients discharged with short DAPT have a relevant risk of ST, which remains high although not significant after DAPT cessation.

P972A subgroup analysis from the RAIN-CARDIOGROUP VII study: incidence of adverse events after DAPT cessation in patients treated with ultrathin stents in ULM or coronary bifurcations

Abstract Introduction Incidence and predictors of adverse events after dual antiplatelet therapy (DAPT) cessation in patients treated with ultrathin stents in unprotected left main (ULM) or coronary bifurcation remain undefined. Methods All consecutive patients presenting with a critical lesion of an ULM or a lesion involving a main coronary bifurcation and treated with very thin strut stents were included. MACE (a composite end point of cardiovascular death, myocardial infarction (MI), target lesion revascularization (TLR) and stent thrombosis (ST) was the primary endpoint, while target vessel revascularization (TVR) was the secondary endpoint. Moreover, type and occurrence of ST and occurrence of ST, CV death and MI during DAPT or after DAPT discontinuation were also evaluated. All analyses were performed according to length of DAPT dividing the patients in 3 groups: short DAPT (3-months), intermediate DAPT (3–12 months) and long DAPT (12-months). Results 117 patients were discharged with an indication for DAPT≤3 months (median 1:1–2.5), 200 for DAPT between 3 and 12 months (median 8:7–10) and 1958 with 12 months DAPT. After 12.8 months (8–20), MACE was significantly higher in the 3-month group compared to 3–12 and 12-month groups (9.4% vs. 4.0% vs. 7.2%, p≤0.001), mainly driven by MI (4.4% vs. 1.5% vs. 3%, p≤0.001) and overall ST (4.3% vs. 1.5% vs. 1.8%, p≤0.001). ST post DAPT cessation were comparable (1.7% vs. 0% vs. 0.7%, p=0.42) with a median time to ST post DAPT discontinuation of 1.67 months (0.48–4.7). At multivariate analysis, DAPT of 12-months compared to 3-months reduces the risk of overall ST (OR 0.103: 0.019–0.0563, 95% CI) while only a trend was noted for DAPT between 3 and 12 months (OR 0.61: 0.186–2.005, 95% CI). When analysed by stent strategy a 2-stent strategy predicted ST post DAPT cessation (OR 3.241: 1.048–10.026, 95% CI), which was reduced by use of FKB (OR 0.101:0.01–0.872, 95% CI). Conclusion Even stents with very thin strut when implanted in real-life ULM or coronary bifurcation patients discharged with short DAPT have a relevant risk of ST, which remains high although not significant after DAPT cessation. The correct identification before PCI of the more fragile patients who may receive a shorter DAPT regimen could help identify the safest PCI technique: provisional stenting and use of final kissing balloon (FKB) are the safest options.

Impact of Final Kissing Balloon and of Imaging on Patients Treated on Unprotected Left Main Coronary Artery With Thin-Strut Stents (From the RAIN-CARDIOGROUP VII Study)

Few data are available about the impact on outcomes of procedural strategies for percutaneous coronary intervention with thin-struts stents on unprotected left main (ULM): 792 patients with an ULM stenosis treated with percutaneous coronary intervention with thin-strut stents were enrolled in the present multicenter registry. Target lesion revascularization (TLR) was the primary end point. MACE (a composite of all-cause death, myocardial infarction, TLR, and stent thrombosis) and its single components, along with target vessel revascularization were the secondary end points. Subgroup analyses were performed according to complex versus noncomplex bifurcation lesions. After 16 months, 5.5% of patients experienced a TLR. At multivariate analysis, provisional stenting (odds ratio [OR] 0.46: 0.85 to 0.23, p = 0.006), use of imaging (OR 0.45: 0.23 to 0.98, p = 0.003) and final kissing balloon (FKB) (OR 0.41: 0.83 to 0.21, p = 0.001) reduced risk of TLR. FKB reduced risk of overall TLR only for 2 stents-strategy (6.2% vs 32.4%, p <0.05), but not for provisional strategy (3.8% vs 3.7%, p = 0.67). Intracoronary imaging reduced risk of overall TLR both for provisional (2.2% vs 5.4%) and for 2-stents strategy (7.3% vs 14.1% p <0.05 for both, all confidence interval 95%). In conclusion, TLR for ULM patients treated with thin-strut stents is infrequent. Provisional stenting was noninferior compared with 2-stents apart from complex lesions. Benefit from intracoronary imaging is consistent for different strategies, whereas that from FKB persists only for 2-stents.

Applying DESyne coronary stent system in patients with ischemic heart disease: experience from Jordan.

BackgroundThe safety and efficacy of drug-eluting coronary stenting have been established for various degrees of severity of coronary artery disease. The DESyne is a contemporary cobalt–chromium thin-strut stent which has been studied in low-risk patients so far.AimThe aim of this study was to evaluate the safety, efficacy and performance of the DESyne stent in patients with an indication for coronary stent implantation at the King Abdullah University Hospital (KAUH), Jordan.Patients and methodsHospital records for all patients implanted with DESyne stent were retrospectively reviewed. Specific clinical events were recorded for all cases, and their incidence rates were estimated by the Kaplan–Meier method. A total of 715 patients (79.3% males and 58.3% with diabetes) with a mean age of 57.8±10.3 years were enrolled in this study. An acute coronary syndrome was the most frequent indication for stenting in 86.3% of the patients (unstable angina 72.0%, myocardial infarction [MI] 14.3%). A total of 849 lesions (1.2 lesions/patient) were treated with the DESyne stent.ResultsAfter 1 year of follow-up, the death rates from cardiac or noncardiac causes were 0.6% and 1.1%, respectively. MI was observed in 0.9% of the cases, and an ischemia-driven revascularization was performed in 0.8% of them. The definite/probable stent thrombosis rate was 1.1%.ConclusionFavorable clinical event rates including cardiac death, MI and stent thrombosis were observed for the DESyne stent in ischemic heart patients especially those with high prevalence of diabetes mellitus and acute coronary syndrome.

Abstract 16775: Efficacy and Safety of a Thinner-strut Silicon Carbide-coated Cobalt Chromium Bare-metal Stent Compared to a Thin-strut Uncoated Cobalt Chromium Bare-metal Stent in Large Vessel Stenting: Insights From Two Prospective Randomised All-comers Trials

Introduction: The new generation thinner-strut silicon carbide (SiC) coated cobalt chromium (CoCr) bare-metal stents (BMS) are designed to accelerate rapid endothelialisation and reduce thrombogenicity when implanted in coronary arteries. However, smaller studies suggest reduced efficacy with higher rates of symptomatic restenosis in patients receiving the newer generation BMS. Objective: We investigated the efficacy and safety of a new generation thinner-strut SiC coated CoCr BMS (SCC-BMS) as compared to an older thin-strut uncoated CoCr BMS (UC-BMS) in patients presenting with coronary artery disease requiring stenting of large vessels (≥3.0mm) and thus at low risk of restenosis. Methods: We included all patients randomized to SCC- (n=761) or UC-BMS (n=765) in the BASKET-PROVE II and I trials, respectively. Design, patients, interventions and follow-up were similar between trials except differing regimens of dual antiplatelet therapy. The primary endpoint was clinically driven target-vessel revascularization within 24 months. Safety endpoints of cardiac death, non-fatal myocardial infarction (MI), and definite/probable stent thrombosis were also assessed. We used Cox proportional hazards regressions to estimate relative hazards adjusting for known confounders. Results: Demographics, clinical presentation, and risk factors were comparable between the groups, but patients receiving SCC-BMS underwent less complex procedures. Rates of the primary endpoint were 10.4% in the SCC-BMS group and 8.4% among patients receiving UC-BMS yielding an adjusted relative hazard (HR) of 1.46 ([1.03-2.07], p=0.032). Estimates for the safety endpoints were: cardiac death (1.8% vs. 2.4% ; HR 0.77 [0.36-1.59], p=0.46), non-fatal MI (3.2% vs. 2.5% ; HR 1.68 [0.88-3.21], p=0.11), and definite/probable stent thrombosis (0.8% vs. 1.0% ; HR 0.97 [0.32-3.00], p=0.96). We detected no particular subgroups driving the increased risk of target-vessel revascularization in the SCC-BMS group. Conclusions: In patients requiring stenting of large coronary arteries, use of the newer generation SCC-BMS was associated with a higher risk of symptomatic restenosis despite less complex procedures compared to the UC-BMS with no signs of an offsetting safety benefit.

TCT-608 A New Thin-Strut, Low-Dose, Sirolimus-Eluting Stent With Abluminal-Only Biodegradable Polymeric Coating: Safety and Efficacy Clinical Performance of the Inspiron™ Stent in High-Risk Patients

The new Inspiron™ (Scitech, Brazil) is a thin-strut (75 μm) cobalt-chromium stent, abluminally coated with a thin (4.4 μg) PLA-PLGA polymeric layer, eluted with low-dose sirolimus. The present study aims to evaluate the safety and efficacy profile of the novel drug-eluting-stent in a very high-