Current-generation Drug-eluting Stents Research Articles

Science, Medicine, and the Anesthesiologist

Science, Medicine, and the Anesthesiologist

Clinical Outcomes After Current-Generation Drug-Eluting Stent Implantation for Ostial Left Circumflex Lesions

BackgroundThere are no available data about clinical outcomes of simple stenting for ostial left circumflex (LCX) lesions using current generation drug-eluting stents (cDES). ObjectiveWe assessed clinical outcomes after simple stenting using cDES for ostial LCX lesions. MethodsWe identified 81 consecutive patients who underwent PCI using cDES for ostial LCX lesions at New Tokyo Hospital, Matsudo, Japan between January 2010 and December 2016. An ostial LCX lesion was defined as a lesion with more than 75% stenosis by visual assessment and within 3 mm of the left main (LM) stem. The primary endpoint was target lesion failure (TLF). TLF was defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction (MI). Additionally, we also assessed the revascularization for LM to left anterior descending artery (LAD) after ostial LCX stenting. ResultsThe TLF rate at 3 years after PCI was 24.5%. Furthermore, the rate of TLR and revascularization for LM-LAD after ostial LCX stenting were significantly higher in patients who were previously undergone stent implantation in ostial segment of LAD. ConclusionClinical outcomes after cDES implantation for ostial LCX lesion could be acceptable. However, it could have better to be avoided in patients who previously received stent implantation in ostial segment of LAD.

Impact of stent edge dissection detected by optical coherence tomography after current-generation drug-eluting stent implantation.

BackgroundStent edge dissection (SED) is a well-known predictor of worse clinical outcomes. However, impact of SED after current-generation drug-eluting stent (DES) implantation remains unknown since there was no study using only current-generation DES to assess impact of SED. This study aimed to investigate a relationship between SED detected by optical coherence tomography (OCT) and clinical outcomes after current-generation DES implantation.MethodsThis study enrolled 175 patients receiving OCT after current-generation DES implantation. The SED group was compared with the non-SED group in terms of the primary study endpoints which was the cumulative incidence of major adverse cardiac event (MACE) composed of cardiac death, target vessel myocardial infarction (TV-MI), and clinically-driven target lesion revascularization (CD-TLR).ResultsOf 175 patients, SED detected by OCT was observed in 32 patients, while 143 patients did not show SED. In the crude population, the SED group showed a significantly higher incidence of CD-TLR, definite stent thrombosis, TV-MI and cardiac death relative to the non-SED group. After adjustment by an inverse probability weighted methods, the SED group showed a significantly higher incidence of MACE compared with the non-SED group (hazard ratio 3.43, 95% confidence interval 1.09–10.81, p = 0.035). Fibrocalcific or lipidic plaques, greater lumen eccentricity, and stent-oversizing were the predictors of SED.ConclusionsSED detected by OCT after the current-generation DES implantation led to unfavorable outcomes. Aggressive post-dilatation around the stent edge might worse clinical outcomes due to SED, although achievement of optimal stent expansion is strongly encouraged to improve clinical outcomes.

Effect of Hinge Motion on Stent Edge-Related Restenosis After Right Coronary Artery Treatment in the Current Drug-Eluting Stent Era.

Stent edge-related restenosis (SER) remains a potential limitation of drug-eluting stent (DES). Hinge motion at the stent edge could lead to mechanical stress and contribute to incidents of SER. We investigated the effect of hinge motion on SER after implantation of current-generation DES in the right coronary artery (RCA), where excessive vessel movement is commonly observed. Of 647 consecutive lesions in the RCA treated with second-generation or later DESs, 426 with follow-up angiography were included in this study. Intravascular imaging analysis was performed for 584 stent edges and reference segments. Binary restenosis occurred in 42 lesions (9.9%), and 55% were SERs. The hinge angle was significantly larger in the SER group than in the other restenosis or the no-restenosis group (17.9° vs. 11.6° and 10.6°, respectively; P<0.001). Lesions with an excessive hinge angle (>11.5°) had an increased rate of target lesion revascularization (19.1% vs. 7.2%; P<0.001) during the median follow-up period of 1,578 days. In per-edge analysis, hinge angle and residual plaque burden were independent predictors of SER. The coexistence of excessive hinge motion and residual plaque burden had a synergistic effect on stenotic progression in quantitative angiographic analysis (Pinteraction<0.001) at follow-up angiography. Substantial stress determined by angulation at a stent edge and its interaction with residual plaque can be considered as one plausible mechanism for SER.

Contributions of small dense LDL and oxidized LDL on the formation of neoatherosclerosis in patients under statin treatment

Abstract Aim In-stent neoatherosclerosis (NA) has emerged as an important contributing factor to late stent failure and cardiovascular events. The aim of this study was to investigate whether lipid markers are associated with NA using optical coherence tomography (OCT) after percutaneous coronary intervention (PCI) in patients with coronary artery disease under well-controlled low density lipoprotein cholesterol (LDL-c) on statin treatment. Methods We enrolled consecutive 115 patients under statin treatment who underwent PCI with current-generation drug-eluting stent for acute and chronic coronary syndrome. OCT image and various lipid markers were obtained at 1-year for scheduled research assessment. NA was defined as a lipid laden neointima or calcified neointima. Both small dense LDL-c (sd-LDL-c) and remnant lipoprotein cholesterol (RL-c) were measured using direct homogenous assay. Results During an average follow-up of 13 months, NA was observed in 14 (13.6%) patients. Not LDL-c but sd-LDL-c, Malondialdehyde-modified LDL (MDA-LDL) as oxidized LDL and (RL-c) were significantly higher in patients with NA. The optimal threshold values of sd-LDL-c, MDA-LDL and RL-c for predicting NA according to receiver operating characteristics analysis were 32.3 mg/dl, 91.0 U/L, and 3.3 mg/dL, respectively. On multivariate logistic regression analysis, sd-LDL-c (≥32.3 mg/dL) and MDA (≥91.0 U/L) were significantly associated with NA (odds ratio [OR]:13.62, p=0.016, OR: 12.68, p=0.01, respectively). Conclusions In statin-treated patients, sd-LDL-c and MDA-LDL but not LDL-c might be useful biomarkers to identify the formation of NA at 1 years after PCI. Aggressive reduction of these atherogenic LDL may have a potential to prevent the formation of NA. Funding Acknowledgement Type of funding sources: None.

3- or 1-Month DAPT in Patients at High Bleeding Risk Undergoing Everolimus-Eluting Stent Implantation.

The aim of this study was to evaluate 2 abbreviated dual-antiplatelet therapy (DAPT) regimens in patients at high bleeding risk (HBR) undergoing percutaneous coronary intervention (PCI). Current-generation drug-eluting stents are preferred over bare-metal stents for HBR patients, but their optimal DAPT management remains unknown. The XIENCE Short DAPT program included 3 prospective, multicenter, single-arm studies enrolling HBR patients who underwent successful PCI with a cobalt-chromium everolimus-eluting stent. After 1month (XIENCE 28 USA and XIENCE 28 Global) or 3months (XIENCE 90) of DAPT, event-free patients discontinued the P2Y12 inhibitor. The postmarketing approval XIENCE V USA study was used as historical control in a propensity score-stratified analysis. A total of 3,652 patients were enrolled. The propensity-adjusted rate of the primary endpoint of all-cause mortality or myocardial infarction was 5.4% among 1,693 patients on 3-month DAPT versus 5.4% in the 12-month DAPT historical control (Pnoninferiority=0.0063) and 3.5% among 1,392 patients on 1-month DAPT versus 4.3% in the 6-month DAPT historical control (Pnoninferiority=0.0005). Bleeding Academic Research Consortium (BARC) types 2 to 5 bleeding was not significantly lower with 3- or 1-month DAPT, while BARC types 3 to 5 bleeding was reduced in both experimental groups. The rate of definite or probable stent thrombosis was 0.2% in XIENCE 90 (P<0.0001 for the performance goal of 1.2%) and 0.3% in XIENCE28. Among HBR patients undergoing PCI with cobalt-chromium everolimus-eluting stents, DAPT for 1 or 3months was noninferior to 6 or 12months of DAPT for ischemic outcomes and may be associated with less major bleeding and a low incidence of stent thrombosis.

Early vascular responses to ultrathin biodegradable polymer sirolimus-eluting stent for the treatment of st-elevation myocardial infarction

Abstract Background Recent clinical study suggests newer-generation drug-eluting stents (DES) that combine ultrathin strut and nano-coating with biodegradable polymers sirolimus-eluting stent (BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) over current generation DES. However, safety profiles in very early phase have not been systematically addressed. Objective and method We exploratory investigate early vascular response following BP-SES implantation in patients with STEMI to reveal mechanism of the favorable clinical outcomes in recent studies using frequency domain-optical coherence tomography (FD-OCT). Consecutive twenty patients with STEMI who underwent FD-OCT immediately after primary PCI and were eligible for follow-up FD-OCT at 2 weeks after implantation were enrolled between June 2018 and November 2019. Results Twenty patients (age 62.7±11.3 years, male 85.0%) were enrolled with frequencies of hypertension (45.0%), diabetes mellitus (35.0%), dyslipidemia (55.0%) and smoking (80.0%). Aspiration catheter were used in all patients, and 1.13±0.34 stents were used. Only one patient (5.0%) received chronic antiplatelet therapy with aspirin prior to the onset of STEMI. All patients started to receive prasugrel as thienopyridine from this event and continued dual antiplatelet therapy for 2 weeks. The percentage of uncovered struts significantly decreased from post-procedure to 2W follow-up (69±18% post-procedure versus 30±11% at 2W follow up, p&amp;lt;0.0001). Malapposed struts also decreased (5.6±5.7% post-procedure versus0.9±1.2% at 2W follow up, p&amp;lt;0.0001).The average protrusion area of athero-thrombotic burden numerically decreased (0.37±0.19 at post-procedure versus 0.34±0.14 mm2 at 2W follow up, p=0.19) and its volume showed similar tendency (10.60±6.40 at post-procedure versus 9.36±5.14 mm3 at 2W follow up, p=0.19). Conclusion(s) This study firstly elucidated very early vascular responses following ultrathin strut BP-SES implantation in STEMI patients, showing early progression of strut coverage and resolution of athero-thrombotic materials. This technology may have a potential to overcome the current generation DESs in this clinical setting. Thrombus, uncovered and malapposed struts Funding Acknowledgement Type of funding source: None

Clinical outcomes of double stent strategy for unprotected left main distal bifurcation lesions using current generation drug eluting stent comparing to early generation drug eluting stent; The Milan and New Tokyo (MITO) registry.

There are only little data available on the comparison of clinical outcomes between a early generation drug eluting stent (eDES) and a current generation drug eluting stent (cDES) for percutaneous coronary intervention (PCI) with double stent strategy (DSS) for unprotected distal left main disease (ULMD). Between April 2005 and December 2015, we recruited 452 consecutive ULMD patients treated with DSS (eDES, 236 patients; cDES, 216 patients). In this study, eDES included Cipher, Taxus, and Endeavor and cDES included Ultimaster, Resolute family, Xience family, Promus family, Synergy, and Nobori. The primary endpoint was target lesion failure (TLF) defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction (MI) during the median follow-up period of 1,809(IQR: 1,190-2,510) days. In entire population, the rate of overall TLR was significantly lower in cDES group than that in eDES group (adjusted HR 0.62, 95% CI 0.40-0.96, p = .032). The rate of TLR for the ostium of LCX was significantly lower in cDES group than that in eDES group (adjusted HR 0.63, 95% CI 0.39-0.99, p = .047). Cardiac mortality, the rate of TLR for LM-LAD, MI and definite/probable ST did not significantly differ between both groups. The results were preserved in the propensity adjusted population. cDES significantly improved the clinical outcomes in population treated with DSS mainly driven by the reduction of TLR for the ostium of LCX.

Angiographic Restenosis in Coronary Bifurcations Treatment with Regular Drug Eluting Stents and Dedicated Bifurcation Drug-Eluting BiOSS Stents: Analysis Based on Randomized POLBOS I and POLBOS II Studies

Aim The marked variation in bifurcation anatomy has brought about an ongoing search for stents specifically constructed for coronary bifurcations. This study aimed to analyze the angiographic restenosis prevalence and patterns and predictors of different patterns in dedicated bifurcation BiOSS® vs. current generation drug-eluting stents implanted in coronary bifurcation lesions based on data from two clinical trials POLBOS I and II. Methods Dedicated bifurcation BiOSS® stents were compared with drug-eluting stents (DES) in patients with stable coronary artery disease (CAD) or nonST elevation acute coronary syndrome (NSTE-ACS) (POLBOS I: paclitaxel eluting BiOSS® Expert vs. DES; POLBOS II: sirolimus eluting BiOSS® LIM vs. DES). Provisional T-stenting was the default treatment. Morphological pattern of in-stent restenosis according to the modified Mehran classification adopted for bifurcation lesions was assessed with bifurcation dedicated quantitative coronary angiographic software (CAAS 5.11, Pie Medical Imaging BV, the Netherlands). Results In total, 445 patients (222 patients in BiOSS group and 223 patients in DES group) were included into the analysis. In BiOSS group 24 cases of angiographic restenosis (10.8%) were recorded, and in DES group—17 cases (7.6%) at 12 months follow-up (angiographic control rate at follow-up—90.3%). In the BiOSS group most frequent medina classification in restenotic cases was 0.0.1 (25%), whereas in DES—0.0.1 and 0.1.1 (23.5% each). In multivariate regression analysis proximal optimization technique was associated with the lowest chance for restenosis (OR 0.15, 95% CI 0.06–0.33), whereas diabetes on insulin was associated with the highest risk of restenosis (OR 4.21, 95% CI 1.48–11.44). Conclusions The angiographic restenosis pattern and rate was similar between BiOSS stents and DES in coronary bifurcation lesions.

The Current Literature on Bioabsorbable Stents: a Review.

The purpose of this review is to explore the evolution of the coronary stent, from the advent of bare-metal stents, to the newest adopted technology of bioresorbable vascular scaffolds (BVS) used in bioresorbable stents. To date, there have been conflicting data regarding the safety and efficacy of BVS stents, especially when compared to current-generation drug-eluting stents (DES). This review will cover the data that exist regarding current BVS stents, as well as the active clinical trials for future iterations of BVS. The ABSORB BVS, the most widely circulated stent of its class, was promised to decrease rates of stent thrombosis and target vessel revascularization. Several randomized control trials, however, found the opposite to be true, with the ABSORB BVS demonstrating higher rates of thrombosis, target vessel revascularization, and even target lesion myocardial infarctions when compared to current-generation DES. These data caused the product to be pulled from all markets, leaving the field with uncertainty as to the role of BVS in coronary interventions. Coronary stents have evolved significantly from 1977, when they were first introduced. The original bare-metal stent was later fitted with a drug-eluting polymer, to prevent restenosis and thrombosis over time. Subsequent iterations of the stent attempted to further mitigate that risk by replacing the durable polymer to one that is bioresorbable. The final step in this progression was to create a stent that was fully bioresorbable, which Abbott did with the creation of their ABSORB BVS stent. The product, however, was found to perform poorly when compared to current-generation drug-eluting stents, with several trials showing high rates of stent thrombosis (ST), late stent thrombosis (LST), target-lesion myocardial infarction, and target vessel revascularization. Observational studies of BVS stents have proposed several mechanisms for their thrombogenicity, including higher stent-strut profiles leading to turbulent flow, low radial strength leading to strut disruption, and a higher propensity for neoatherosclerosis. Given the failure of the first-generation BVS stent, but the lingering desire for fully bioresorbable scaffolds, various manufacturers have proposed their solutions with new stents. Until data from their clinical trials emerge, it remains unclear whether fully bioresorbable stents will play any role in coronary interventions.

P6530Clinical outcomes of dialysis patients treated with current generation DES for left main distal bifurcation

Abstract Objectives We assessed clinical outcomes after percutaneous coronary intervention (PCI) for unprotected left main (ULM) using current generation drug eluting stents (cDES) in hemodialysis (HD) patients compared to general populations. Methods We identified 1269 consecutive patients who underwent PCI for ULM distal bifurcation lesions. Of them, 563 patients were treated with cDES (512 non HD and 51 HD patients). The primary endpoint was target lesion failure (TLF) at 3 years, defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction (MI). Results HD group was more likely to have diabetes mellitus (70.0% vs. 45.8%, p=0.002), peripheral artery disease (56.0% vs. 14.9%, p&lt;0.001), and lower ejection fraction (52.6% vs. 56.3%, p=0.026). The rate of TLF at 3 years was significantly higher in the HD group (adjusted Hazard ratio [HR] 2.59; 95% confidence interval [CI], 1.54–4.37; p&lt;0.001). Cardiac mortality was significantly higher in the HD group (adjusted HR 4.49; 95% CI, 2.07–9.74; p&lt;0.001). The rates of TLR for LM-left anterior descending artery (LAD) and left circumflex ostium (LCXos) were significantly higher in the HD group (LMT-LAD: adjusted HR 3.10; 95% CI, 1.31–7.33; p=0.01, LCXos: adjusted HR 2.56; 95% CI, 1.32–4.94; p=0.005). The rate of MI was similar between the 2 groups. Conclusions Hemodialysis was strongly associated with adverse events after PCI for ULM distal bifurcation lesions even with cDES.

Percutaneous Coronary Intervention: Developments in the Last 12 Months

In 2018, there were several studies that significantly added to the field of interventional cardiology. Research was focused on understanding the role of percutaneous coronary intervention (PCI) in various clinical syndromes, optimizing outcomes for high-risk lesion subsets, and building an evidence base for greater adoption of PCI guided by physiology and intracoronary imaging. In the area of innovation, novel and iterative developments in drug-eluting stents (DES) and scaffold platforms were compared with current generation DES. This article summarizes the research from last year which has had the most impact on PCI techniques and clinical care.

Long-Term Clinical Outcomes and Optimal Stent Strategy in Left Main Coronary Bifurcation Stenting

ObjectivesThis study sought to investigate the long-term clinical effects of stent generation and stent strategy for left main coronary artery (LMCA) bifurcation lesion treatment. BackgroundLimited data are available to assess long-term clinical outcomes after stenting, including use of current-generation drug-eluting stent (C-DES) for treatment of LMCA bifurcation lesions. MethodsA total of 1,353 patients who were recorded in 2 multicenter real-world registries were treated by either early-generation drug-eluting stent (E-DES) (n = 889) or C-DES (n = 464). Primary endpoint was major adverse cardiovascular events (MACE). MACE was defined as a composite of cardiac death or myocardial infarction, stent thrombosis, and target lesion revascularization rates during 3-year follow-up. The authors further performed propensity-score adjustment for clinical outcomes. ResultsDuring 3-year follow-up, the overall MACE rate was 8.7%. Use of a 1-stent strategy resulted in better clinical outcomes than use of a 2-stent strategy (4.7% vs. 18.6%, hazard ratio [HR]: 3.71; 95% confidence interval [CI]: 2.55 to 5.39; p < 0.001). Use of C-DES resulted in a lower MACE rate compared with using E-DES (4.6% vs. 10.9%, HR: 0.55; 95% CI: 0.34 to 0.89; p = 0.014), especially for the 2-stent strategy. For patients with C-DES, the presence of chronic kidney disease and pre-intervention side branch diameter stenosis ≥50% were significant independent predictors of MACE. ConclusionsIntervention of LMCA bifurcation lesions using DES implantation demonstrated acceptable long-term clinical outcomes, especially in C-DES patients. Use of a 1-stent strategy resulted in better clinical benefits than using a 2-stent strategy.

Temporal course of vascular healing and neoatherosclerosis after implantation of durable- or biodegradable-polymer drug-eluting stents.

Delayed healing and endothelial dysfunction may occur with drug-eluting stents (DES), promoting accelerated infiltration of lipids in the neointima and development of neoatherosclerosis (NA). Pathology data suggest durable polymer (DP) of DES to play a major role in this process. Whether biodegradable polymer (BP) may address these issues is uncertain. We compared in vivo vessel healing and NA of current generation BP- or DP-DES using serial optical coherence tomography (OCT) assessments. Ninety patients with multivessel coronary artery disease were randomized 1:1 to BP everolimus-eluting stents (EES, Synergy) or DP zotarolimus-eluting stents (ZES, Resolute Integrity). Co-primary endpoints were the maximum length of uncovered struts at 3 months (powered for non-inferiority) and the percentage of patients presenting with frames of NA at 18 months (powered for superiority) as measured by OCT. The maximum length of uncovered struts at 3 months was 10 ± 8 mm in the BP-EES group and 11 ± 7 mm in the DP-ZES group (mean difference -1 mm; upper 97.5% confidence interval +2 mm; P = 0.05 for non-inferiority; P = 0.45 for superiority). The percentage of patients presenting with frames of NA at 18 months was low and similar between BP-EES and DP-ZES groups (11.6% vs. 15.9%; P = 0.56). There was no stent thrombosis in both groups at 24 months. BP-EES and DP-ZES showed a similar healing response at 3 months and a low incidence of NA at 18 months. Biocompatible polymers, regardless of whether they are durable or biodegradable, may favourably impact the long-term vascular response to current-generation DES.

6-month versus 12-month or longer dual antiplatelet therapy after percutaneous coronary intervention in patients with acute coronary syndrome (SMART-DATE): a randomised, open-label, non-inferiority trial

Current guidelines recommend dual antiplatelet therapy (DAPT) of aspirin plus a P2Y12 inhibitor for at least 12 months after implantation of drug-eluting stents (DES) in patients with acute coronary syndrome. However, available data about the optimal duration of DAPT in patients with acute coronary syndrome undergoing percutaneous coronary intervention are scant. We aimed to investigate whether a 6-month duration of DAPT would be non-inferior to the conventional 12-month or longer duration of DAPT in this population. We did a randomised, open-label, non-inferiority trial at 31 centres in South Korea. Patients were eligible if they had unstable angina, non-ST-segment elevation myocardial infarction, or ST-segment elevation myocardial infarction, and underwent percutaneous coronary intervention. Enrolled patients were randomly assigned, via a web-based system by computer-generated block randomisation, to either the 6-month DAPT group or to the 12-month or longer DAPT group, with stratification by site, clinical presentation, and diabetes. Assessors were masked to treatment allocation. The primary endpoint was a composite of all-cause death, myocardial infarction, or stroke at 18 months after the index procedure in the intention-to-treat population. Secondary endpoints were the individual components of the primary endpoint; definite or probable stent thrombosis as defined by the Academic Research Consortium; and Bleeding Academic Research Consortium (BARC) type 2-5 bleeding at 18 months after the index procedure. The primary endpoint was also analysed per protocol. This trial is registered with ClinicalTrials.gov, number NCT01701453. Between Sept 5, 2012, and Dec 31, 2015, we randomly assigned 2712 patients; 1357 to the 6-month DAPT group and 1355 to the 12-month or longer DAPT group. Clopidogrel was used as a P2Y12 inhibitor for DAPT in 1082 (79·7%) patients in the 6-month DAPT group and in 1109 (81·8%) patients in the 12-month or longer DAPT group. The primary endpoint occurred in 63 patients in the 6-month DAPT group and in 56 patients in the 12-month or longer DAPT group (cumulative event rate 4·7% vs 4·2%; absolute risk difference 0·5%; upper limit of one-sided 95% CI 1·8%; pnon-inferiority=0·03 with a predefined non-inferiority margin of 2·0%). Although all-cause mortality did not differ significantly between the 6-month DAPT group and the 12-month or longer DAPT group (35 [2·6%] patients vs 39 [2·9%]; hazard ratio [HR] 0·90 [95% CI 0·57-1·42]; p=0·90) and neither did stroke (11 [0·8%] patients vs 12 [0·9%]; 0·92 [0·41-2·08]; p=0·84), myocardial infarction occurred more frequently in the 6-month DAPT group than in the 12-month or longer DAPT group (24 [1·8%] patients vs ten [0·8%]; 2·41 [1·15-5·05]; p=0·02). 15 (1·1%) patients had stent thrombosis in the 6-month DAPT group compared with ten (0·7%) in the 12-month or longer DAPT group (HR 1·50 [95% CI 0·68-3·35]; p=0·32). The rate of BARC type 2-5 bleeding was 2·7% (35 patients) in the 6-month DAPT group and 3·9% (51 patients) in the 12-month or longer DAPT group (HR 0·69 [95% CI 0·45-1·05]; p=0·09). Results from the per-protocol analysis were similar to those from the intention-to-treat analysis. The increased risk of myocardial infarction with 6-month DAPT and the wide non-inferiority margin prevent us from concluding that short-term DAPT is safe in patients with acute coronary syndrome undergoing percutaneous coronary intervention with current-generation DES. Prolonged DAPT in patients with acute coronary syndrome without excessive risk of bleeding should remain the standard of care. Abbott Vascular Korea, Medtronic Vascular Korea, Biosensors Inc, and Dong-A ST.

Rationale and design of the comparison between a P2Y12 inhibitor monotherapy versus dual antiplatelet therapy in patients undergoing implantation of coronary drug-eluting stents (SMART-CHOICE): A prospective multicenter randomized trial

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor reduces thrombotic events in patients undergoing percutaneous coronary intervention (PCI), but these benefits come at the expense of increased risk of bleeding when compared with aspirin monotherapy. It is unclear whether P2Y12 inhibitor monotherapy might maintain anti-ischemic efficacy while reducing the bleeding risk compared with DAPT after implantation of the current generation of drug-eluting stents (DES). The SMART-CHOICE trial is a prospective, open-label, multi-center, and randomized study designed to test the non-inferiority of P2Y12 inhibitor monotherapy compared with aspirin plus a P2Y12 inhibitor after mandatory 3-month DAPT in patients undergoing PCI with current-generation DES. A total of 3000 patients will be randomized to 1 of the 2 antiplatelet treatment strategy groups. Randomization will be stratified by stent type (cobalt-chromium everolimus-eluting stents, platinum-chromium everolimus-eluting stents, and sirolimus-eluting stents with bioresorbable polymer), P2Y12 inhibitors (clopidogrel, prasugrel, and ticagrelor), clinical presentation (acute coronary syndrome and stable ischemic heart disease), and investigational centers. The primary end point is a composite of all-cause death, myocardial infarction, and cerebrovascular events at 12 months after the index procedure. The key secondary end points are definite/probable stent thrombosis defined by the Academic Research Consortium, and bleeding defined by Bleeding Academic Research Consortium type 2-5. The SMART-CHOICE trial aims to examine the non-inferiority of monotherapy with one of any available oral P2Y12 inhibitors versus conventional DAPT of an identical P2Y12 inhibitor plus aspirin in a broad spectrum of patients receiving representative current-generation DES.

Optical Frequency Domain Imaging Versus Intravascular Ultrasound in Percutaneous Coronary Intervention (OPINION Trial): Results From the OPINION Imaging Study

ObjectivesThe authors sought to clarify how intravascular ultrasound (IVUS) and optical coherence tomography affect percutaneous coronary intervention (PCI) with current-generation drug-eluting stents in a pre-specified substudy of the OPINION (OPtical frequency domain imaging versus INtravascular ultrasound in percutaneous coronary interventiON) trial, a multicenter, prospective, randomized, noninferiority trial comparing optical frequency domain imaging (OFDI)-guided PCI with IVUS-guided PCI. BackgroundThe impact of these 2 imaging modalities in guiding PCI remains unknown. MethodsOf 829 patients enrolled in the OPINION trial, 106 were included in the present imaging substudy. Their PCI was guided by either IVUS or OFDI, but all patients were imaged by both modalities after PCI and by OFDI at 8 months. Angiographic, OFDI, and IVUS images were analyzed by independent core laboratories, and statistical analysis was done independently by a dedicated institution. ResultsA total of 103 patients underwent either OFDI-guided (n = 54) or IVUS-guided (n = 49) PCI. Immediately after PCI, OFDI-guided PCI was associated with a smaller trend of minimum stent area (5.28 ± 1.65 mm2 vs. 6.12 ± 2.34 mm2; p = 0.088), fewer proximal stent-edge hematomas (p = 0.04), and fewer irregular protrusions (p = 0.014) than IVUS-guided PCI. At 8 months, the neointima area tended to be smaller in the OFDI-guided PCI group than in the IVUS-guided PCI group (0.56 ± 0.30 mm2 vs. 0.80 ± 0.65 mm2; p = 0.057), although the percentage of uncovered struts was significantly higher in the OFDI-guided PCI group than in the IVUS-guided PCI group (6.97 ± 7.03% vs. 4.67 ± 6.43%; p = 0.039). The minimum lumen area was comparable in both groups (p = 0.18). ConclusionsThere were several differences in local findings between OFDI- and IVUS-guided PCI as expected given the different protocols for stent sizing in the 2 groups. The minimum lumen area at the 8-month follow-up was comparable, suggesting that OFDI- and IVUS-guided PCI are similarly feasible using the current-generation drug-eluting stents. (OPtical frequency domain imaging versus INtravascular ultrasound in percutaneous coronary interventiON; NCT01873222)

Contemporary Drug-Eluting Stents and Vascular Response

Cardiovascular disease is a leading cause of death and disability worldwide. Current treatment strategies aimed at treating the consequences of coronary artery disease have embraced both optimal medical therapy and catheter based percutaneous coronary intervention with drug-eluting stents (DES). Current-generation DES elute predominantly mammalian target of rapamycin (mTOR) inhibitors, which act primarily as a cytostatic agent that retards vascular smooth muscle cell proliferation and migration; this occurs in response to injury and thus prevents restenosis. While DES have reduced restenosis, the use of first-generation DES was associated with an increased risk of late stent thrombosis and accelerated neointimal atherosclerosis (i.e. neoatherosclerosis), both major contributors to late stent failure. The underlying substrate of late DES failure is likely related to vascular endothelial dysfunction, which occurs after DES implantation. Initial concerns with first-generation DES have led to improvements in stent design, polymer load and biocompatibility, and pharmacologic agents, all of which have helped to improve healing responses, lessen late stent failure, and result in an overall improved safety profile. The armamentarium of DES has expanded from the current-generation durable polymer DES to bioresorbable polymer DES, polymer-free DES, and lastly totally bioresorbable vascular scaffolds with a goal of improving vascular responses and endothelial function while preserving anti-restenotic efficacy. We will review these contemporary DES in relation to their short and long-term effects on vascular biocompatibility and healing responses.

DESyne novolimus-eluting coronary stent is superior to Endeavor zotarolimus-eluting coronary stent at five-year follow-up: final results of the multicentre EXCELLA II randomised controlled trial.

Newer-generation drug-eluting stents (DES) have been shown to be superior to first-generation DES. Current-generation DES have zotarolimus, everolimus or biolimus as antiproliferative drugs. Novolimus, a metabolite of sirolimus, has been specifically developed to provide efficacy similar to currently available agents at a lower dose and thus requires a lower polymer load. We report the final five-year outcomes of the EXCELLA II trial comparing a zotarolimus-eluting stent (ZES) with a novolimus-eluting stent (NES). EXCELLA II is a prospective, multicentre, single-blind, non-inferiority clinical trial. Patients (n=210) with a maximum of two de novo lesions in two different epicardial vessels were randomised (2:1) to treatment with either NES (n=139) or ZES (n=71). At five-year follow-up, patients in the NES group had a significantly lower incidence of the patient-oriented (HR 0.53, 95% CI: 0.32-0.87, p=0.013) and device-oriented (HR 0.38, 95% CI: 0.17-0.83, p=0.011) composite endpoints. There was no difference in cardiac death and definite/probable stent thrombosis between the two groups; however, there was a trend towards reduction in myocardial infarction and repeat revascularisation in the NES group at five-year follow-up. At five-year follow-up, the incidence of device- and patient-oriented events was significantly lower in the NES group. Further studies, adequately powered for clinical outcomes, are warranted.

The Absorb bioresorbable vascular scaffold for the treatment of coronary artery disease

ABSTRACTIntroduction: Every decade the field of interventional cardiology is revolutionized by new technology. The fully bioresorbable everolimus-eluting scaffold (ABSORB BVS) technology would preserve the benefits of metallic stents by sealing balloon-induced dissections, avoiding elastic recoil and vessel occlusion. The polymeric scaffold would be resorbed to restore the natural integrity of the vessel, superseding the consequence of the permanent presence of a foreign body in the coronary artery.Areas covered: This technology evaluation focuses on the clinical evidence for the use of bioresorbable everolimus-eluting scaffold for the treatment of coronary artery disease.Expert opinion: The current generation of the bioresorbable scaffold has structural and mechanical limitations that might preclude the widespread use in clinical practice. The strut thickness (150 µm) limits deliverability and creates laminar flow disruptions that might be the nidus of an increased rate of scaffold thrombosis. In the next generation of bioresorbable scaffolds, the resorption process should be faster and in particular, strut thickness must be reduced. This will probably represent a significant step forward in an attempt to increase the efficacy and safety profile of the device and achieve a similar performance with the current generation drug-eluting stent even in complex scenarios.