Tissue coverage of a hydrophilic polymer-coated zotarolimus-eluting stent vs. a fluoropolymer-coated everolimus-eluting stent at 13-month follow-up: an optical coherence tomography substudy from the RESOLUTE All Comers trial

Randomized Comparison of Novel Low-Dose Sirolimus-Eluting Biodegradable Polymer Stent vs Second-Generation DES: TARGET-IV NA Trial

BACKGROUND

Drug-eluting stents (DESs) with controlled antiproliferative drug release reduce restenosis risk, but durable polymers can delay healing and inhibit reendothelialization. The Firehawk biodegradable polymer sirolimus-eluting stent (BP-SES) has a fully biodegradable sirolimus-containing polymer coating localized to recessed abluminal grooves on the stent surface and delivers roughly one-third the drug dose of other DESs.

OBJECTIVES

We report the primary results of the TARGET-IV NA (Firehawk Rapamycin Target Eluting Coronary Stent North American Trial) randomized controlled trial comparing clinical outcomes with BP-SES vs currently used second-generation DESs.

METHODS

The TARGET-IV NA study was a prospective, multicenter, single-blind, 1:1 randomized noninferiority trial comparing the BP-SES with control in North America and Europe among patients undergoing percutaneous coronary intervention for chronic or acute coronary syndromes. The primary endpoint was target lesion failure (TLF) at 12 months (composite of cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization). The primary analysis (intention-to-treat) tested noninferiority of BP-SES vs control using an absolute margin of 3.85% and 1-sided α of 0.025. Noninferiority-powered secondary endpoints were tested in an optical coherence tomography substudy (endpoint: mean neointimal hyperplasia thickness) and an angiography substudy (endpoint: in-stent late lumen loss).

RESULTS

A total of 1,720 patients (mean age 66 years; 74% male) with 2,159 lesions were randomly allocated to receive either BP-SES (860 patients, 1,057 lesions) or control second-generation DES (860 patients, 1,084 lesions). A total of 61% of patients presented with stable coronary disease, 32% had unstable angina, and 7% had non-ST-segment elevation myocardial infarction (NSTEMI) or recent ST-segment elevation myocardial infarction. The rate of TLF with BP-SES was noninferior to control at 12 months (3.4% vs 3.3%, absolute risk difference 0.13%, upper bound 97.5% CI: 2.03, Pnoninferiority < 0.0001). Cardiac death, myocardial infarction, and stent thrombosis rates were similar between groups. Angiographic follow-up was available in 104 patients (97.2% of those enrolled in the angiographic substudy) and 128 (94.1%) lesions. At 13 months, the powered secondary endpoint of mean in-stent late lumen loss was 0.149 ± 0.263 mm for BP-SES and 0.327 ± 0.463 mm for control (least squares mean difference: -0.178; 90% CI: -0.2943 to -0.0632; Pnoninferiority < 0.0001). The optical coherence tomography substudy included 37 patients (42 lesions) with no difference in mean neointimal hyperplasia thickness between groups at 13 months (Pnoninferiority = 0.01).

CONCLUSIONS

The biodegradable polymer sirolimus-eluting stent was noninferior to currently used second-generation DES with regard to TLF at 1 year. (Firehawk® Rapamycin Target Eluting Coronary Stent North American Trial; NCT04562532).

Direct Comparison of Rotational vs Orbital Atherectomy for Calcified Lesions Guided by Optical Coherence Tomography

BACKGROUND

There are several retrospective studies comparing rotational atherectomy (RA) and orbital atherectomy (OA), but all percutaneous coronary interventions (PCIs) in those studies were not performed under intracoronary imaging guidance.

OBJECTIVES

This study sought to compare the efficacy and safety of optical coherence tomography (OCT)-guided PCI with RA vs OA.

METHODS

The DIRO (To directly compare RA and OA for calcified lesions, a prospective randomized trial) trial was conducted. We enrolled patients with de novo calcified lesions (arc >180°) assessed by OCT or angiographically moderate or severe calcifications if the OCT catheter could not cross the lesion before any intervention. Eligible patients were randomly 1:1 allocated to lesion preparation with RA vs OA. Stent expansion was defined as the minimum stent area divided by the distal reference area multiplied by 100. Tissue modification was assessed using preatherectomy and postatherectomy OCT images. Procedural outcomes including periprocedural myocardial infarctions were evaluated. Furthermore, clinical events and vascular healing evaluated by OCT at 8 months postprocedure were assessed.

RESULTS

The stent expansion was significantly greater in the RA group vs the OA group (99.5% vs 90.6%; P = 0.02). The maximum atherectomy area was significantly larger in the RA group than in the OA group (1.34 [IQR: 1.02-1.89] mm2 vs 0.83 [IQR: 0.59-1.11] mm2; P = 0.004). The procedural outcomes and clinical events at 8 months did not differ between the groups. The vascular healing was sufficient in both groups.

CONCLUSIONS

The prospective randomized DIRO trial revealed that RA could produce a more favorable tissue modification, which may lead to a larger stent expansion than OA in heavily calcified lesions.

The Outcome of Ultrathin-Strut Biodegradable Polymer-Coated Sirolimus-Eluting Stents in Coronary Artery Disease Patients - A Feasibility Study

Background

Drug-eluting coronary stents with ultrathin struts and biodegradable polymers have been shown to reduce inflammation, neointimal proliferation, and thrombus formation, leading to less early and late complications in patients with coronary artery disease as compared to thinner strut and durable polymer second-generation stents. In Oman, currently, second-generation stents are used for all patients.

Objective

The purpose of this feasibility study was to evaluate the clinical safety and performance of ultrathin-strut (60 μm) biodegradable polymer-coated sirolimus-eluting stents in an all-comers patient population.

Methods

This was a prospective, observational, single-center, and single-arm investigator-initiated study from August 2018 to August 2019. Inclusion criteria: 18 years of age, patients with symptomatic coronary artery disease indicated for percutaneous coronary intervention, and stenting of at least one coronary lesion. All patients were followed clinically or telephonically at 12 months after the index procedure.

Results

A total of 88 patients were recruited in the study, but 10 patients were lost to follow-up and hence excluded from the analysis. The overall mean age was 63 ± 13 years and 78% were males. The main comorbid conditions were hypertension (58%), diabetes mellitus (49%), and hyperlipidemia (26%). Fifty-three percent presented with unstable angina or non-ST elevation myocardial infarction (MI), 10% with ST elevation MI, recent MI 16%, 18% with stable angina, and 1.3% in cardiogenic shock. The mean left ventricular ejection fraction of the cohort was 46 ± 14%. Angiographically, Type A lesions were seen in 25%, Type B in 32%, and Type C in 42%. Left anterior descending stenting was done in 44%, right coronary artery in 32%, left circumflex artery in 14%, left main in 5%, and graft stenting in 4%. Device success was 96%. Procedural success was seen in 97% of patients. At 1-year follow-up, 93% were asymptomatic; overall device-oriented clinical events were 6.8% including cardiac death in 2.7%, target-vessel MI in 2.7%, and target-lesion revascularization in 1.3% which all occurred in uncontrolled diabetic patients.

Conclusions

At index admission and 1 year, ultrathin-strut biodegradable polymer-coated sirolimus-eluting stent study showed low device-related adverse clinical events which are comparable to published data for the second-generation stents. This feasibility study shows that these stents can be used in all types of stent-indicated patients with added advantages of biodegradable polymer and ultrathin struts. In addition, measures to prevent, diagnose, and control diabetes need to be taken in Oman as this cohort of patients develop ST after stenting.

Evolution of drug-eluting coronary stents: a back-and-forth journey from the bench-to-bedside

Coronary stents have revolutionized the treatment of coronary artery disease. Compared with balloon angioplasty, bare-metal stents effectively prevented abrupt vessel closure but were limited by in-stent restenosis due to smooth muscle cell proliferation and neointimal hyperplasia. The first-generation drug-eluting stent (DES), with its antiproliferative drug coating, offered substantial advantages over bare-metal stents as it mitigated the risk of in-stent restenosis. Nonetheless, they had several design limitations that increased the risk of late stent thrombosis. Significant advances in stent design, including thinner struts, enhanced polymers' formulation, and more potent antiproliferative agents, have led to the introduction of new-generation DES with a superior safety profile. Cardiologists have over 20 different DES types to choose from, each with its unique features and characteristics. This review highlights the evolution of stent design and summarizes the clinical data on the different stent types. We conclude by discussing the clinical implications of stent design in high-risk subsets of patients.

Safety and Efficacy of Contemporary Drug-Eluting Stents in Patients With ST-Segment Elevation Myocardial Infarction and a High Ischemic Risk

Background

In patients with ST-elevation myocardial infarction (STEMI) with a high risk of ischemic events, the safety and efficacy of drug-eluting stent (DES) are unclear.

Methods

Based on the nationwide, multicenter, prospective registry, we selected 1,592 patients who underwent primary percutaneous coronary intervention (PCI) with everolimus-(EES) and zotarolimus-eluting stent (ZES) for STEMI with a high risk of an ischemic event. The occurrence of target lesion failure (TLF) for 3 years, defined as the composite of cardiac death, target vessel myocardial infarction (TV-MI), and ischemia-driven target lesion revascularization (ID-TLR), was evaluated.

Results

The prevalence of high ischemic risk features was observed in 43.4% (2,744/6,325) of overall patients with STEMI. Among them, a total of 1,078 and 514 patients were treated with EES and ZES, respectively. At 3 years, the risk of TLF was not significantly different between the two groups (p = 0.93). In addition, the incidence of cardiac death, TV-MI, ID-TLR, and definite/probable stent thrombosis (ST) were also not different between the two groups. Moreover, elderly patients (age > 75 years) and PCI for the left main disease were identified as independent predictors of TLF.

Conclusion

Implantation of EES or ZES provided comparable clinical outcomes in STEMI patients and high ischemic risks.

Healing and early stent coverage after ultrathin strut biodegradable polymer-coated sirolimus-eluting stent implantation: SiBi optical coherence tomography study

AIMS

The aim of SiBi study was to evaluate the early vascular healing and neointimal coverage after implantation of ultrathin (60 μm) biodegradable polymer-coated Tetriflex (Sahajanand Medical Technologies Pvt. Ltd., Surat, India) sirolimus-eluting stent (SES) using optical coherence tomography (OCT) at 4 to 6 weeks after implantation.

METHODS

SiBi was a single-center, observational, investigator-initiated study. From January 15, 2018 to April 15, 2018, total 29 consecutive patients who had consented and underwent OCT examination at 4-6 weeks after Tetriflex SES implantation were enrolled. All OCT images were analyzed at an independent core laboratory by analysts who were blinded to patient and procedural information.

RESULTS

Of 29 patients, four patients were excluded, as those OCT images were technically inadequate for analysis. Therefore, 25 patients were included in final OCT analysis. Average OCT analysis was performed after 35.3 ± 5 days of Tetriflex implantation. Total 14,024 stent struts in 1,520 cross sections were analyzed. Strut tissue coverage was observed in 91.26 ± 5.53% of struts and malapposed struts were seen in 0.89 ± 1.67%. The mean neointimal hyperplasia (NIH) thickness on the covered struts was 50 ± 30 μm.

CONCLUSION

A large percentage of struts were found to be covered with thin layer of NIH evenly distributed along the stent length at around 1 month from stent implantation. The results of this pilot study serve as ethical and scientific backbone to conduct an adequately powered clinical trial to evaluate outcomes of short dual-antiplatelet therapy in context of ultrathin strut stent.

Identification of the type of stent with three-dimensional optical coherence tomography: the SPQR study

BACKGROUND

The ability of optical coherence tomography (OCT) to identify specific types of stent has never been systematically studied.

AIMS

The aim of this study was to test the accuracy of OCT imaging to identify patterns of stent platform and subsequently identify the type of stent implanted.

METHODS

Consecutive patients from six international centres were retrospectively screened, searching for OCT studies with metallic stents or scaffolds. The sample was analysed by two blinded operators, applying a dedicated protocol in four steps to identify the type of stent: 1) 3D and automatic strut detection (ASD), 2) 3D tissue view, 3) longitudinal view with ASD, 4) mode "stent only" and ASD.

RESULTS

A series of 212 patients underwent OCT in the study centres, finding 294 metallic stents or scaffolds in 146 patients. The protocol correctly identified 285 stents (96.9%, kappa 0.965), with excellent interobserver agreement (kappa 0.988). The performance tended to be better in recently implanted stents (kappa 0.993) than in stents implanted ≥3 months before (kappa 0.915), and in pullback speed 18 mm/s as compared with 36 mm/s (kappa 0.969 vs 0.940, respectively).

CONCLUSIONS

The type of stent platform can be accurately identified in OCT by trained analysts following a dedicated protocol, combining 3D-OCT, ASD and longitudinal view. This might be clinically helpful in scenarios of device failure and for the quantification of apposition. The blinding of analysts in OCT studies should be revisited.

Impact of diabetes mellitus on vascular healing process after everolimus-eluting stent implantation: An optical coherence tomography study

BACKGROUND/PURPOSE

To study the impact of diabetes mellitus (DM) on vascular healing process after implantation of everolimus-eluting stent (EES).

METHODS/MATERIALS

Data from 3 prospective studies (HEAL-EES, REVER, and RESERVOIR), including patients with EES implantation and OCT follow-up, were merged. Differences in vascular healing process assessed by OCT were compared between DM and non-DM using generalized estimating equations. Neointimal proliferation, neointimal signal pattern (high, low, and layered), and uncovered/malapposed struts were evaluated.

RESULTS

A total of 96 lesions (61 DM lesions and 35 non-DM lesions) were included. Mean OCT follow-up time was 8.9 ± 1.5 months and comparable between groups. DM were older, high frequently female and acute coronary syndrome, and received smaller stent than non-DM. No differences were observed in quantitative vascular healing process between groups. However, DM exhibited higher low and layered signal pattern neointima compared to non-DM at lesion level (p = 0.030) and cross-section level (p < 0.001). Uncovered/malapposed struts were comparable between groups.

CONCLUSIONS

Quantitative vascular healing process was comparable between groups. However, DM was significantly associated with low signal pattern, which is characteristic of focal inflammation, after EES implantation. Further study might be required to study relationship between neointimal signal pattern and clinical events.

The role of intracoronary imaging in translational research

Atherosclerotic cardiovascular disease is a key public health concern worldwide and leading cause of morbidity, mortality and health economic costs. Understanding atherosclerotic plaque microstructure in relation to molecular mechanisms that underpin its initiation and progression is needed to provide the best chance of combating this disease. Evolving vessel wall-based, endovascular coronary imaging modalities, including intravascular ultrasound (IVUS), optical coherence tomography (OCT) and near-infrared spectroscopy (NIRS), used in isolation or as hybrid modalities, have been advanced to allow comprehensive visualization of the pathological substrate of coronary atherosclerosis and accurately measure temporal changes in both the vessel wall and plaque characteristics. This has helped further our appreciation of the natural history of coronary artery disease (CAD) and the risk for major adverse cardiovascular events (MACE), evaluate the responsiveness to conventional and experimental therapeutic interventions, and assist in guiding percutaneous coronary intervention (PCI). Here we review the use of different imaging modalities for these purposes and the lessons they have provided thus far.

Difference of vascular healing between bioabsorbable-polymer and durable-polymer new generation drug-eluting stents: an optical coherence tomographic analysis

The comparison of bioabsorbable-polymer and durable-polymer stents has continued to be debated, and there is ongoing concern regarding vascular healing and late stent thrombosis. This study compared the vascular healing at 8-month follow-up by optical coherence tomography (OCT) between 4 different kinds of new generation drug-eluting stents (DESs). We enrolled 112 patients (112 de novo lesions) who underwent OCT guided percutaneous coronary intervention with 4 kinds of new generation DESs including bioabsorbable-polymer everolimus-eluting stents (BP-EESs), bioabsorbable-polymer sirolimus-eluting stents (BP-SESs), durable-polymer everolimus-eluting stents (DP-EESs), and durable-polymer zotarolimus-eluting stents (DP-ZESs) and an 8-month follow-up angiogram and OCT were performed between July 2016 and April 2018. We divided them into two groups, namely BP and DP groups. We compared the OCT parameters including the percentage of uncovered struts, malapposed struts and the mean neointimal hyperplasia (NIH) thickness between the two groups. BP group consisted of 51 lesions (BP-EESs were used in 27, BP-SESs in 24 lesions) and DP group consisted of 61 lesions (DP-EESs were used in 35 and DP-ZESs in 26 lesions). The percentage of uncovered struts and malapposed struts were significantly lower (7.2 ± 8.9 vs. 15.0 ± 17.1%, p = 0.01, 0.9 ± 1.7 vs. 2.7 ± 5.2%, p = 0.03) and the mean NIH thickness was significantly thicker in BP group than DP group (112 ± 54 vs. 83 ± 31 µm, p < 0.01). The present OCT study demonstrated that uncovered struts and malapposed struts were less common with bioabsorbable-polymer stents than with durable-polymer stents.

Efficacy of Zotarolimus-Eluting Stents in Treating Diabetic Coronary Lesions: An Optical Coherence Tomography Study

BACKGROUND

Diabetes mellitus (DM) plays an important role in restenosis and late in-stent thrombosis (ST). The current study using optical coherence tomography (OCT) aims to compare target lesion neointima in patients with or without diabetes after zotarolimus-eluting stent (ZES) treatment.

METHODS

OCT images of 90,212 struts and quantitative coronary angiography (QCA) in 62 patients (32 with DM and 30 without DM) with 69 de novo coronary lesions (34 DM and 35 non-DM) both after ZES implantation and 12 ± 1 month angiographic follow-up were recorded. Patient characteristics, lesion characteristics, clinical outcomes, and OCT findings including neointimal thickness, coverage, malapposition, and intimal morphology were analyzed.

RESULTS

Baseline patient characteristics and lesion characteristics data were similar between the two groups. Higher neointimal thickness (0.14 ± 0.09 mm vs. 0.09 ± 0.04 mm, p = 0.021), more neovascularization (3.03 ± 6.24 vs. 0.52 ± 1.87, p = 0.017) and higher incidence of layered signal pattern (12.19 ± 19.91% vs. 4.28 ± 9.02%, p = 0.049) were observed in diabetic lesions comparing with non-diabetic lesions. No differences were found in malapposition, uncovered percentage, and thrombus between the two groups (all p > 0.05). Occurrence of clinical adverse events was also similar during the follow-up period (p > 0.05).

CONCLUSION

Although more neointimal proliferation and more neovascularization were found in diabetic coronary lesions when compared with non-diabetic lesions, treatment with ZES showed similar stent malapposition rate at 1-year follow-up. The data indicated that ZES treatment could possibly be effective in treating diabetic coronary lesions.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT01747356.

Device profile of the Resolute Onyx Zotarolimus eluting coronary stent system for the treatment of coronary artery disease: overview of its safety and efficacy

Introduction: The increasing complexity of patients undergoing percutaneous coronary intervention (PCI) regarding both coronary anatomy and comorbidities requires dedicated devices. The Resolute Onyx (R-Onyx, Medtronic, CA, USA) stent is a novel durable polymer zotarolimus-eluting stent (ZES) promising better deliverability, increased radiopacity and lower thrombogenicity.Areas covered: In this review, we discuss device features, preclinical evidence, and clinical studies including patients treated with R-Onyx. The BIONYX and Onyx ONE studies were two major landmark trials demonstrating non-inferiority of R-Onyx as compared to other latest generation devices. We also elaborate on alternative innovations in drug-eluting stent (DES) technology and how R-Onyx fits into this field.Expert opinion: R-Onyx is designed to address the challenges of contemporary PCI, but evidence on its clinical performance is largely derived from studies on older generation devices from the ZES family. Nonetheless, all clinical studies on R-Onyx consistently show excellent outcomes, with particularly low rates of stent thrombosis, making it a promising candidate for short dual antiplatelet regimens. In addition, R-Onyx is available with a wide range of stent diameters allowing accurate sizing for both very small and very large coronary vessels.

Prospective evaluation of an ultrathin strut biodegradable polymer-coated sirolimus-eluting stent: 12 months' results from the S-FLEX UK registry

OBJECTIVE

To prospectively evaluate safety and efficacy of the ultrathin strut biodegradable polymer-coated Supraflex sirolimus-eluting stent (S-SES) in 'real world' patient population requiring percutaneous coronary intervention (PCI).

METHODS

National, prospective, multicentre, single-arm, all-comers, observational registry of 469 patients treated with S-SES from July 2015 and November 2016 in 11 centres in UK. Primary endpoint was target lesion failure (TLF) at 12 months (cardiac death, target vessel myocardial infarction (MI) or clinically driven target lesion revascularisation (TLR)). Secondary endpoints included safety and performance outcomes at 12 months-overall stent thrombosis (ST), all-cause mortality, any MI, target vessel failure (TVF) and major adverse cardiac events (MACE-composite of cardiac death, MI, emergent or repeat revascularisation).

RESULTS

At 12 months, the primary endpoint occurred in 11 (2.4%) of 466 patients, consisting of 4 (0.9%) cardiac deaths, 3 (0.6%) target vessel MI and 7 (1.5%) TLR. Secondary endpoints findings included all-cause mortality in 6 (1.3%), TVF of 14 (3%), no definite ST, 1 (0.2%) probable ST and 3 (0.6%) possible ST. Overall MACE was observed in 18 (3.9%).

CONCLUSIONS

The S-FLEX UK registry showed that the S-SES is safe with a low incidence of TLF in routine clinical practise in patients with coronary artery disease being treated by PCI.

Incidence of late-acquired stent malapposition of drug eluting stents with second generation permanent and biodegradable polymer coatings-A prospective, randomized comparison using optical coherence tomography

OBJECTIVES AND BACKGROUND

Polymer coatings of drug-eluting stents (DES) may induce allergic reactions and inflammation, resulting in late-acquired stent malapposition (LASM) with the risk of stent thrombosis. This study evaluated, if biodegradable polymer (BP) reduces the incidence of LASM compared to permanent polymer (PP) after treatment with newer generation DES.

METHODS AND RESULTS

Fifty patients with 59 lesions were randomized (2:1) to elective treatment with second generation PP-DES (n = 32, 39 stents), either Everolimus-eluting or Zotarolimus-eluting stents, or with BP-DES (Biolimus-eluting stents [BES]; n = 18, 20 stents) and underwent optical coherence tomography directly after implantation and after 1 year. After implantation acute stent malappositions (ASM) were documented in 30 stents (51%) distributed to 22 stents treated with PP-DES (56%) and 8 with BP-DES (40%; n.s.). After 1 year, late stent malappositions (LSM) were detected in 14 stents (24 %); ASM persisted (APSM) in 9 stents after one year (7 PP-DES-18%, 2 BES-10%), whereas ASM resolved in 21 stents. In addition, LASM was documented in nine stents including five stents without and four stents with additional APSM. All LASM were located in PP-DES (n = 9; 23%), none in BP-DES (P = 0.022). Compared to the reference lumen area, in-stent lumen area of stents without LASM was smaller due to neointimal hyperplasia (P = 0.021), whereas in-stent lumen area at maximum LASM of stents with LASM was larger due to positive remodeling (P = 0.002).

CONCLUSIONS

In conclusion the use of BP-DES reduced the occurrence of LASM due to positive remodeling compared to second generation PP-DES.

Serial Assessment of Strut Coverage of Biodegradable Polymer Drug-Eluting Stent at 1, 2, and 3 Months After Stent Implantation by Optical Frequency Domain Imaging: The DISCOVERY 1TO3 Study (Evaluation With OFDI of Strut Coverage of Terumo New Drug Eluting Stent With Biodegradable Polymer at 1, 2, and 3 Months)

BACKGROUND

To assess the vessel-healing pattern of Ultimaster drug-eluting stent using optical frequency domain imaging. Our hypothesis is that biodegradable polymer-based drug-eluting technology allows complete very early strut coverage.

METHODS AND RESULTS

The DISCOVERY 1TO3 study (Evaluation With OFDI of Strut Coverage of Terumo New Drug Eluting Stent With Biodegradable Polymer at 1, 2, and 3 Months) is a prospective, single-arm, multicenter study. A total of 60 patients with multivessel disease requiring staged procedure at 1 month were treated with Ultimaster. Optical frequency domain imaging was acquired at baseline, 1, 2, and 3 months. The primary end point is optical frequency domain imaging-assessed strut coverage at 3 months. Mean age of patients was 67.2±9.9 years, and 73.3% were male, and 36.7% presented with acute coronary syndrome. A total of 132 lesions were treated, with average 1.4 lesions per patient treated at baseline and 1.1 lesions treated at 1 month. Strut coverage at 3 months of single implanted stents (n=71, primary end point) was 95.2±5.2% and of combined single and overlapped stents was 95.4±4.9%. Strut coverage of combined single and overlapped stents at 1 (n=49) and 2 months (n=38) was 85.1±12.7% and 87.9±10.8%, respectively. The median neointimal hyperplasia thickness was 0.04, 0.05, and 0.06 mm, whereas mean neointimal hyperplasia obstruction was 4.5±2.4%, 5.2±3.4%, and 6.6±3.3% at 1, 2, and 3 months, respectively.

CONCLUSIONS

Nearly complete strut coverage was observed in this complex population very early after implantation of Ultimaster drug-eluting stent.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01844843.

The OCT-ORION Study: A Randomized Optical Coherence Tomography Study Comparing Resolute Integrity to Biomatrix Drug-Eluting Stent on the Degree of Early Stent Healing and Late Lumen Loss

BACKGROUND

Durable polymers used in drug-eluting stents are considered a potential cause of hypersensitivity inflammatory response adversely affecting stent healing. Using a sequential follow-up with optical coherence tomography, we compared the differences in healing profiles of 2 drug-eluting stents with a biodegradable or durable polymer.

METHODS AND RESULTS

Sixty patients with multivessel disease were prospectively enrolled to receive both study stents, which were randomly assigned to 2 individual vessels, a Resolute Integrity zotarolimus-eluting stent with a durable BioLinx polymer and a BioMatrix NeoFlex Biolimus A9-eluting stent with a biodegradable polylactic acid polymer. Optical coherence tomography was performed at baseline, then in 5 randomly assigned monthly groups at 2 to 6 months, and at 9 months in all patients. The primary end point was the difference in optical coherence tomography strut coverage at 9 months. Key secondary end points included angiographic late lumen loss and composite major adverse cardiac events (cardiac death, myocardial infarction, target lesion revascularization, and definite or probable stent thrombosis) at 9 months. Resolute Integrity zotarolimus-eluting stent showed significantly better strut coverage than BioMatrix NeoFlex Biolimus A9-eluting stent at 2 to 6 months (P<0.001) and less variance of percent coverage at 9 months, 99.7% (interquartile range, 99.1-100) versus 99.6% (interquartile range, 96.8-99.9; difference, 0.10; 95% confidence interval, 0.00-1.05; P<0.001). No significant difference was observed in major adverse cardiac events or angiographic end points.

CONCLUSIONS

Despite having a durable polymer, Resolute Integrity zotarolimus-eluting stent exhibited better strut coverage than BioMatrix NeoFlex Biolimus A9-eluting stent having a biodegradable polymer; both showed similar antiproliferative efficacy. This novel, longitudinal, sequential optical coherence tomography protocol using each patient as own control could achieve conclusive results in small sample size.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01742507.

Three-months optical coherence tomography analysis of a biodegradable polymer, sirolimus-eluting stent

OBJECTIVE

We aimed to assess early neointimal healing by optical coherence tomography (OCT) 3 months after implantation of the ultrathin Orsiro® sirolimus-eluting stent with biodegradable polymer.

BACKGROUND

New generations of drug-eluting stents with biodegradable polymer have been developed to avoid the continued vascular irritation of durable polymers.

METHODS

In this prospective, open-label study, 34 patients received an Orsiro® sirolimus-eluting stent with biodegradable polymer. In a subgroup of patients (n = 15), the intervention was performed under OCT guidance. All patients underwent OCT-examination at three months. The primary endpoint was 3-month neointimal healing (NIH) score, calculated by weighing the presence of filling defects, malapposed and uncovered struts. Secondary endpoint was maturity of tissue coverage at 3 months.

RESULTS

At 3 months, NIH score was 13.7 (5.4-22), covered struts per lesion were 90% (84-97%), malapposed struts were 2.7% (0.8-5.4%) and rate of mature tissue coverage was 47% (42-53%). No target lesion failure occurred up to 12 months. Patients with OCT-guided stent implantation demonstrated a trend toward earlier stent healing as demonstrated by superior NIH scores (angio guided: 17.6% [8.8-26.4]; OCT-guided: 9.8% [4.0-15.5]; mean difference -8, [95%CI: -18.7-2.9], P = 0.123). This group had significantly more covered struts per lesion (angio-guided: 86% [82-90]; 95% [92-99]; mean difference 9% [95%CI: 3-15], P = 0.001).

CONCLUSION

The Orsiro® sirolimus-eluting stent with biodegradable polymer shows early vascular healing with a high rate of strut coverage at 3-month follow-up. OCT guided stent implantation had a positive impact on early vascular healing.

Second-generation drug-eluting stents versus drug-coated balloons for the treatment of coronary in-stent restenosis: A systematic review and meta-analysis

PURPOSE

The benefit of drug-eluting stents (DES) versus drug-coated balloons (DCB) in coronary artery in-stent restenosis (ISR) for the prevention of target lesion revascularization (TLR), stent thrombosis, and mortality remains uncertain. Our aim was to synthesize the available evidence from randomized clinical trials (RCTs) and observational studies that directly compare second-generation drug-eluting stents (SG-DES) and DCB for the treatment of coronary ISR.

METHODS

Medline, Embase, and Cochrane Central were searched for RCTs or observational studies, published up to March 15, 2017. A random effects model meta-analysis investigating clinical and angiographic outcomes was conducted for RCTs and observational studies that compared SG-DES versus DCB for the treatment of ISR.

RESULTS

Ten studies and 2,173 patients were included in this meta-analysis. The two treatment strategies were proven equal with regards to TLR, myocardial infarction, stent thrombosis, and cardiac mortality in both randomized and observational studies. No difference was found among RCTs for all-cause mortality, while in observational studies, patients who were treated with SG-DES had a lower mortality compared to DCB (OR: 0.47; 95% CI: 0.27-0.83). In the pooled analysis also (RCTs and observational studies), SG-DES were associated with lower all-cause mortality compared to DCB. Patients treated with SG-DES were also superior in terms of minimal lumen diameter (standardized mean difference: 0.39; 95% CI: 0.12-0.66).

CONCLUSIONS

The two treatment strategies are equal for the treatment of ISR, while the difference in all-cause mortality might be potentially explained by baseline differences in the two groups among real-world studies.

Comparative assessment of three drug eluting stents with different platforms but with the same biodegradable polymer and the drug based on quantitative coronary angiography and optical coherence tomography at 12-month follow-up

The aim of this study was to compare neointima proliferation in three drug-eluting stents (DES) produced by the same company (Balton, Poland) which are covered with a biodegradable polymer and elute sirolimus (concentration: 1.0 and 1.2 µg/mm²), but have different stent platforms and strut thickness: stainless steel Prolim^® (115 µm) and BiOSS LIM^® (120 µm) and cobalt-chromium Alex^® (70 µm). We analyzed data of patients with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 12 months from BiOSS LIM Registry, Prolim Registry and Alex OCT clinical trial. There were 56 patients enrolled, in whom 29 Prolim^® stents were deployed, in 11-BiOSS LIM^® and in 16-Alex stents. The late lumen loss was the smallest in Prolim^® subgroup (0.26 ± 0.17 mm) and did not differ from Alex^® subgroup (0.28 ± 0.47 mm). This parameter was significantly bigger in BiOSS^® subgroup (0.38 ± 0.19 mm; p < 0.05). In OCT analysis there was no statistically significant difference between Prolim^® and Alex^® subgroups in terms of mean neointima burden (24.6 ± 8.6 vs. 19.27 ± 8.11%) and neointima volume (28.16 ± 15.10 vs. 24.51 ± 17.64 mm³). In BiOSS^® group mean neointima burden (30.9 ± 6.2%) and mean neointima volume (44.9 ± 4.9 mm³) were significantly larger. The morphological analysis revealed that in most cases in all groups the neointima was homogenous with plaque presence only around stent struts. In the QCA and OCT analysis regular DES (Prolim^® and Alex^®) obtained similar results, whereas more pronounced response from the vessel wall was found in the BiOSS^® subgroup.

Optical coherence tomography follow-up 18 months after titanium-nitride-oxide-coated versus everolimus-eluting stent implantation in patients with acute coronary syndrome

Background Inadequate neointimal coverage of stent struts is associated with late stent thrombosis. Purpose To demonstrate the extent of neointimal coverage and strut malapposition in titanium-nitride-oxide-coated bioactive stents (BAS) versus everolimus-eluting stents (EES) by optical coherence tomography (OCT) performed at 18-month follow-up. Material and Methods In the BASE-ACS trial, 827 patients presenting with acute coronary syndrome were randomized to receive either BAS or EES. Forty patients (20 BAS, 20 EES) underwent OCT at 18-month follow-up for evaluation of stent strut coverage, malapposition, and neointimal hyperplasia (NIH). Primary endpoint was binary stent strut coverage (ratio of covered struts to all analyzed struts multiplied by 100). Co-primary endpoint was the percentage of malapposed struts. Results We analyzed 3465 struts in 330 cross-sections of BAS and 3327 struts in 316 cross-sections of EES. Binary stent strut coverage, based on strut-level analysis, was higher with BAS versus EES (99.5% versus 94.2%, respectively; P < 0.001), the strut-level percentage of malapposed struts was lower with BAS (0.6% versus 2.5%, respectively; P < 0.001). Yet, the mean NIH thickness was greater with BAS (237 ± 125 versus 108 ± 62 µm, respectively; P < 0.001). Conclusion In the current post-hoc analysis with OCT performed at 18 months, binary strut coverage, based on strut-level analysis, was higher with BAS versus EES; strut-level malapposed struts were fewer with BAS; yet, BAS induced thicker NIH.

Neointimal Healing Evaluated by Optical Coherence Tomography after Drug-Eluting Absorbable Metal Scaffold Implantation in de novo Native Coronary Lesions: Rationale and Design of the Magmaris-OCT Study

Objectives: We sought to explore neointimal healing assessed by optical coherence tomography (OCT) following implantation of the Magmaris sirolimus-eluting absorbable metal scaffold. Methods: The Magmaris-OCT is a prospective, multicenter, single-arm observational clinical study, intended to enrol 60 consecutive patients with up to 2 de novo native coronary lesions, each located in different major epicardial vessels, with a reference vessel diameter of 2.5-3.5 mm, and a maximum lesion length of 20 mm. Patients will undergo Magmaris scaffold implantation in the target lesion, according to the standard practice. Clinical follow-up will take place at 30 days, and at 3, 6, 9, and 12 months. For invasive-imaging follow-up, patients will be classified into 3 groups: cohort A will be scheduled for follow-up at 3 months, cohort B at 6 months, and cohort C at 12 months. Invasive imaging will include quantitative coronary angiography, OCT evaluation, and coronary flow reserve measurement. The primary end point will be the percentage of uncovered scaffold struts assessed by OCT at the prespecified follow-up. Conclusions: This study will provide insight into the short- and mid-term healing properties following Magmaris scaffold implantation, with special emphasis on the neointimal coverage of scaffold struts.

Zotarolimus-eluting Resolute Integrity versus everolimus-eluting Xience Xpedition stents in the management of very long (>30mm) de novo coronary artery stenosis

BACKGROUND

Procedural and clinical outcomes in patients with very long (>30mm) coronary lesions who underwent stent-based percutaneous coronary interventions are still unfavorable. Therefore, we compared the relative efficacy and safety of resolute zotarolimus-eluting stents (R-ZES) and Xpedition everolimus-eluting stents (X-EES) for patients with de novo very long coronary lesions.

METHODS

This comparative single-centre, retrospective study compared long R-ZES and X-EES in consecutive patients admitted with very long (≥30mm) native ACC/AHA type C coronary lesions in 2014. All patients were followed up clinically at 1, 3, 6 and 12months. In this study, only symptom-driven angiogram was advised. The study end point was to evaluate immediate procedural success and one-year rate of target lesion failure (TLF), which is a composite of cardiac death, target lesion myocardial infarction, or target lesion revascularization (TLR).

RESULTS

Total number of patients enrolled in this study was 185 (R-ZES=107; X-EES=78). The baseline characteristics and post procedural success rate were similar between R-ZES and X-EES groups, including the post stenting lesion lengths (36.6±1.92mm vs 40.71±6.175mm, P=0.09). At 12-month follow-up, there were no significant between-group differences in the rate of adverse clinical events (death, myocardial infarction, stent thrombosis, target lesion revascularization, and composite outcomes). Procedural success was achieved in 94% in R-ZES group and 93% in X-EES group (P=0.24). The incidence of TLF was 5% in R-ZES and 4% in X-EES groups (HR-1.25; 95% CI-0.86-5.6; P=0.19).

CONCLUSION

Patients with de novo long coronary artery disease, R-ZES implantation showed similar clinical outcome as compared with X-EES implantation.

A chemical stability study of trimethylsilane plasma nanocoatings for coronary stents

Trimethylsilane (TMS) plasma nanocoatings were deposited onto stainless steel coupons in direct current (DC) and radio frequency (RF) glow discharges and additional NH₃/O₂ plasma treatment to tailor the coating surface properties. The chemical stability of the nanocoatings were evaluated after 12 week storage under dry condition (25 °C) and immersion in simulated body fluid (SBF) at 37 °C. It was found that nanocoatings did not impact surface roughness of underlying stainless steel substrates. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy were used to characterize surface chemistry and compositions. Both DC and RF nanocoatings had Si- and C-rich composition; and the O- and N-contents on the surfaces were substantially increased after NH₃/O₂ plasma treatment. Contact angle measurements showed that DC-TMS nanocoating with NH₃/O₂ treatment generated very hydrophilic surfaces. DC-TMS nanocoatings with NH₃/O₂ treatment showed minimal surface chemistry change after 12 week immersion in SBF. However, nitrogen functionalities on RF-TMS coating with NH₃/O₂ post treatment were not as stable as in DC case. Cell culture studies revealed that the surfaces with DC coating and NH₃/O₂ post treatment demonstrated substantially improved proliferation of endothelial cells over the 12 week storage period at both dry and wet conditions, as compared to other coated surfaces. Therefore, DC nanocoatings with NH₃/O₂ post treatment may be chemically stable for long-term properties, including shelf-life storage and exposure to the bloodstream for coronary stent applications.

A Randomized Comparison of Reservoir-Based Polymer-Free Amphilimus-Eluting Stents Versus Everolimus-Eluting Stents With Durable Polymer in Patients With Diabetes Mellitus: The RESERVOIR Clinical Trial

OBJECTIVES

The aim of this study was to compare the efficacy of amphilimus-eluting stents (AES) with that of everolimus-eluting stents (EES) in patients with diabetes mellitus (DM).

BACKGROUND

The AES is a polymer-free drug-eluting stent that elutes sirolimus formulated with an amphiphilic carrier from laser-dug wells. This technology could be associated with a high efficacy in patients with DM.

METHODS

This was a multicenter, randomized, noninferiority trial. Patients with DM medically treated with oral glucose-lowering agents or insulin and de novo coronary lesions were randomized in a 1:1 fashion to AES or EES. The primary endpoint was the neointimal (NI) volume obstruction assessed by optical coherence tomography at 9-month follow-up.

RESULTS

A total of 116 lesions in 112 patients were randomized. Overall, 40% were insulin-treated patients, with a median HbA1c of 7.3% (interquartile range: 6.7% to 8.0%). The primary endpoint, NI volume obstruction, was 11.97 ± 5.94% for AES versus 16.11 ± 18.18% for EES, meeting the noninferiority criteria (p = 0.0003). Pre-specified subgroup analyses showed a significant interaction between stent type and glycemic control (p = 0.02), with a significant reduction in NI hyperplasia in the AES group in patients with the higher HbA1c (p = 0.03). By quantitative coronary angiography, in-stent late loss was 0.14 ± 0.24 for AES versus 0.24 ± 0.57 mm for EES (p = 0.27), with a larger minimal lumen diameter at follow-up for AES (p = 0.02), mainly driven by 2 cases of occlusive restenosis in the EES group.

CONCLUSIONS

AES are noninferior to EES for the coronary revascularization of patients with DM. These results suggest a high efficacy of the AES and may support the potential benefit of this stent in patients with DM. (A Randomized Comparison of Reservoir-Based Polymer-Free Amphilimus-Eluting Stents Versus Everolimus-Eluting Stents With Durable Polymer in Patients With Diabetes Mellitus [RESERVOIR]; NCT01710748).

Very early tissue coverage after drug-eluting stent implantation: an optical coherence tomography study

The aim of this study was to evaluate neointimal coverage in the very early phase after second-generation drug-eluting stent (DES) implantation using optical coherence tomography (OCT). Patients who underwent staged percutaneous coronary intervention within 30 days after DES implantation were enrolled. OCT was performed to observe DES previously implanted. The median time interval from implantation to OCT examination was 21.5 days. A total of 10,625 struts of 54 stents (52 everolimus-eluting stents and 2 zotarolimus-eluting stents) in 42 lesions were analyzed. Strut tissue coverage was observed in 71.1 ± 19.2 % of the struts, malapposed struts in 2.56 ± 3.37 %, strut tissue coverage at the side branch orifice in 10.6 ± 17.2 %, and struts with protrusion in 0.95 ± 3.46 %. Mean tissue thickness on the covered struts was 39.8 ± 14.2 µm. The percentage of stent coverage was significantly lower in the overlapping segments than in the non-overlapping segments (48.4 ± 17.5 % vs. 74.4 ± 20.2 %, P < 0.05). Most of the stent struts were covered by tissue within 30 days after second-generation DES implantation. However, the percentage of strut coverage was lower in the overlapping segments than in the non-overlapping segments, suggesting that very early interruption of dual antiplatelet therapy might result in increased risk of stent thrombosis, even in second-generation DES.

Evaluation of Early Healing Profile and Neointimal Transformation Over 24 Months Using Longitudinal Sequential Optical Coherence Tomography Assessments and 3-Year Clinical Results of the New Dual-Therapy Endothelial Progenitor Cell Capturing Sirolimus-Eluting Combo Stent

Background—

Current monotherapy drug-eluting stents are associated with impaired healing, neoatherosclerosis, and late stent thrombosis. The healing profile and neointimal transformation of the first dual-therapy endothelial progenitor cell–capturing sirolimus-eluting stent are unknown.

Methods and Results—

In this prospective, single-center study, 61 patients treated with the Combo stent had optical coherence tomography at baseline, early follow-up (4 monthly groups in a 1:2:2:1 ratio from 2 to 5 months), 9 months, and 24 months. Optical coherence tomography early strut coverage increased from 77.1% to 92.5% to 92.7% to 94.9% between 2 and 5 months. At 9 months, the major adverse cardiac event rate was 1.64%, and angiographic in-stent late loss was 0.24 mm (0.08–0.40). The 36-month major adverse cardiac event rate was 3.3%. From 9 to 24 months, neointimal regression was confirmed by optical coherence tomography: neointimal thickness (median [first quartile and third quartile]), 0.14 mm (0.08 and 0.21) versus 0.12 mm (0.07 and 0.19), P <0.001; neointimal volume, 29.9 mm 3 (22.1 and 43.2) versus 26.2 mm 3 (19.6 and 35.8), P =0.003; and percent neointimal volume, 17.8% (12.2 and 21.2) versus 15.7% (11.2 and 19.4), P =0.01. No definite or probable late stent thrombosis was recorded.

Conclusions—

With additional endothelial progenitor cell–capturing technology, the Combo stent exhibits a unique late neointimal regression (from 9 to 24 months) that has not been reported in any drug-eluting stents, translating into good 36-month clinical results with minimal restenosis and no late stent thrombosis. This is the first study testing the concept of using a longitudinal sequential optical coherence tomography protocol to continuously document early healing profile and late neointimal transformation, predicting long-term outcomes of a new novel stent platform.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifiers: NCT01274234, NCT01756807, and NCT02263313.

Bioresorbable vascular scaffolds: design, clinical trials, and current applications

In recent years, bioresorbable vascular scaffolds (BVS) have been introduced into clinical practice. The main advantage of BVS is that they overcome the problem of the foreign body in the treated artery. BVS, once placed into narrowed coronary vessels, behave like a conventional drug-eluting stent, but a device that disappears over time can preserve the anatomy and physiology of the treated vessel. The progression of stenosis after stenting has been attributed, at least in part, to inflammation around metallic struts, that, however, disappears gradually when using BVS. BVS have proven to be effective and safe as drug-eluting stents; in fact, the rate of adverse cardiovascular events and scaffold thrombosis in patients is low. The aim of this review article is to provide a comprehensive and updated description of the status of the art on BVS, highlighting the current evidence and future perspectives of this technology.

Clinical outcomes in 995 unselected real-world patients treated with an ultrathin biodegradable polymer-coated sirolimus-eluting stent: 12-month results from the FLEX Registry

OBJECTIVES

To evaluate, in the FLEX Registry, clinical outcomes of an ultrathin (60 µm) biodegradable polymer-coated Supraflex sirolimus-eluting stent (SES) for the treatment of coronary artery disease. Additionally, to determine the vascular response to the Supraflex SES through optical coherence tomography (OCT) analysis.

SETTING

Multicentre, single-arm, all-comers, observational registry of patients who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India.

PARTICIPANTS

995 patients (1242 lesions) who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India. A total of 47 participants underwent OCT analysis at 6 months' follow-up.

INTERVENTIONS

Percutaneous coronary intervention with Supraflex SES, PRIMARY AND SECONDARY OUTCOME MEASURES: The primary endpoint-the rate of major adverse cardiac events (defined as a composite of cardiac death, myocardial infarction (MI), target lesion revascularisation (TLR))-was analysed during 12 months.

RESULTS

At 12 months, the primary endpoint occurred in 36 (3.7%) of 980 patients, consisting of 18 (1.8%) cardiac deaths, 16 (1.6%) MI, 7 (0.7%) TLR and 2 (0.2%) cases of non-target lesion target vessel revascularization. In a subset of 47 patients, 1227 cross-sections (9309 struts) were analysed at 6 months by OCT. Overall, a high percentage of struts was covered (98.1%), with a mean neointimal thickness of 0.13 ± 0.06 µm.

CONCLUSIONS

The FLEX Registry evaluated clinical outcomes in real-world and more complex cohorts and thus provides evidence that the Supraflex SEX can be used safely and routinely in a broader percutaneous coronary intervention population. Also, the Supraflex SES showed high percentage of stent strut coverage and good stent apposition during OCT follow-up.

Safety and efficacy of resolute zotarolimus-eluting stents compared with everolimus-eluting stents: a meta-analysis

BACKGROUND

Although new-generation drug-eluting stents represent the standard of care among patients undergoing percutaneous coronary intervention, there remains debate about differences in efficacy and the risk of stent thrombosis between the Resolute zotarolimus-eluting stent (R-ZES) and the everolimus-eluting stent (EES). The aim of this study was to evaluate the safety and efficacy of the R-ZES compared with EES in patients undergoing percutaneous coronary intervention.

METHODS AND RESULTS

A systematic literature search of electronic resources was performed using specific search terms until September 2014. Random-effects meta-analysis was performed comparing clinical outcomes between patients treated with R-ZES and EES up to maximum available follow-up. The primary efficacy end point was target-vessel revascularization. The primary safety end point was definite or probable stent thrombosis. Secondary safety end points were cardiac death and target-vessel myocardial infarction. Five trials were identified, including a total of 9899 patients. Compared with EES, R-ZES had similar risks of target-vessel revascularization (risk ratio [RR], 1.06; 95% confidence interval [CI], 0.90-1.24; P=0.50), definite or probable stent thrombosis (RR, 1.26; 95% CI, 0.86-1.85; P=0.24), cardiac death (RR, 1.01; 95% CI, 0.79-1.30; P=0.91), and target-vessel myocardial infarction (RR, 1.10; 95% CI, 0.89-1.36; P=0.39). Moreover, R-ZES and EES had similar risks of late definite or probable very late stent thrombosis (RR, 1.06; 95% CI, 0.53-2.11; P=0.87). No evidence of significant heterogeneity was observed across trials.

CONCLUSIONS

R-ZES and EES provide similar safety and efficacy among patients undergoing percutaneous coronary intervention.

Everolimus-eluting bioresorbable stent vs. durable polymer everolimus-eluting metallic stent in patients with ST-segment elevation myocardial infarction: results of the randomized ABSORB ST-segment elevation myocardial infarction-TROFI II trial

AIMS

Patients with ST-segment elevation myocardial infarction (STEMI) feature thrombus-rich lesions with large necrotic core, which are usually associated with delayed arterial healing and impaired stent-related outcomes. The use of bioresorbable vascular scaffolds (Absorb) has the potential to overcome these limitations owing to restoration of native vessel lumen and physiology at long term. The purpose of this randomized trial was to compare the arterial healing response at short term, as a surrogate for safety and efficacy, between the Absorb and the metallic everolimus-eluting stent (EES) in patients with STEMI.

METHODS AND RESULTS

ABSORB-STEMI TROFI II was a multicentre, single-blind, non-inferiority, randomized controlled trial. Patients with STEMI who underwent primary percutaneous coronary intervention were randomly allocated 1:1 to treatment with the Absorb or EES. The primary endpoint was the 6-month optical frequency domain imaging healing score (HS) based on the presence of uncovered and/or malapposed stent struts and intraluminal filling defects. Main secondary endpoint included the device-oriented composite endpoint (DOCE) according to the Academic Research Consortium definition. Between 06 January 2014 and 21 September 2014, 191 patients (Absorb [n = 95] or EES [n = 96]; mean age 58.6 years old; 17.8% females) were enrolled at eight centres. At 6 months, HS was lower in the Absorb arm when compared with EES arm [1.74 (2.39) vs. 2.80 (4.44); difference (90% CI) -1.06 (-1.96, -0.16); Pnon-inferiority < 0.001]. Device-oriented composite endpoint was also comparably low between groups (1.1% Absorb vs. 0% EES). One case of definite subacute stent thrombosis occurred in the Absorb arm (1.1% vs. 0% EES; P = ns).

CONCLUSION

Stenting of culprit lesions with Absorb in the setting of STEMI resulted in a nearly complete arterial healing which was comparable with that of metallic EES at 6 months. These findings provide the basis for further exploration in clinically oriented outcome trials.

Vascular response to bioresorbable polymer sirolimus-eluting stent vs. permanent polymer everolimus-eluting stent at 9-month follow-up: an optical coherence tomography sub-study from the CENTURY II trial

AIMS

The Ultimaster bioresorbable polymer sirolimus-eluting stent (BP-SES) is a newly developed drug-eluting stent (DES) that consists of a thin-strut, cobalt chromium with bioresorbable polymer coated only albuminally. We sought to compare tissue coverage in coronary lesions treated with BP-SES with the XIENCE permanent polymer everolimus-eluting stent (PP-EES) using optical coherence tomography (OCT).

METHODS AND RESULTS

A total of 36 patients participated in the CENTURY II trial in our institution and were randomly assigned to BP-SES (n = 15) and PP-EES (n = 21). Of these, 27 patients (13 BP-SES and 14 PP-EES) underwent OCT at 9-month follow-up. Tissue coverage and apposition were assessed on each strut, and the results in both groups were compared using multilevel logistic or linear regression models with random effects at three levels: patient, lesion, and struts. A total of 6450 struts (BP-SES, n = 2951; PP-EES, n = 3499) were analysed. Thirty and 79 uncovered struts (1.02 and 2.26%, P = 0.35), and 3 and 4 malapposed struts (0.10 and 0.11%, P = 0.94) were found in BP-SES and PP-EES groups, respectively. Mean neointimal thickness did not significantly differ between both groups (110 ± 10 vs. 93 ± 10 µm, P = 0.22). No significant differences in per cent neointimal volume obstruction (13.2 ± 4.6 vs. 10.5 ± 4.9%, P = 0.14) or other areas-volumetric parameters were detected between both groups.

CONCLUSION

BP-SES shows an excellent vascular healing response at 9-month follow-up, which is similar to PP-EES.