Comparison of everolimus-eluting and sirolimus-eluting coronary stents: 1-year outcomes from the Randomized Evaluation of Sirolimus-eluting Versus Everolimus-eluting stent Trial (RESET)

Bioresorbable Vascular Scaffolds - Are We Facing a Time of Crisis or One of Breakthrough?

Current 2nd-generation drug-eluting stents (DES) have dramatically improved clinical outcomes after percutaneous coronary intervention for coronary artery disease. However, DES implantation has major long-term limitations related to the permanent presence of foreign material in the coronary artery. Bioresorbable vascular scaffolds (BVS) were designed to overcome this limitation of permanent metal-based DES. However, because of immature manufacturing technology, BVS have several drawbacks, such as the thicker strut, poor deliverability, poor radio-opacity, poor radial strength, and cumbersome procedure to meet the principle of PSP (Preparation, Sizing, and Post-dilatation). Initial studies indicated that BVS outcomes were non-inferior to those of current DES and recent follow-up data of trials have revealed an additional critical drawback, higher rate of scaffold thrombosis, on the top of the existing limitations of BVS. Thus attention must be paid to the appropriate BVS-specific implantation protocols (i.e., PSP), as well as adequate intensity and duration of dual antiplatelet therapy. In any case, current BVS need further technical evolution to replace current metallic DES in routine clinical use.

Contemporary Drug-Eluting Stent Platforms: Design, Safety, and Clinical Efficacy

First-generation drug-eluting stents significantly improved treatment of coronary disease, decreasing rates of revascularization. This was offset by high rates of late adverse events, driven primarily by stent thrombosis. Research and design improvements of individual DES platform components led to next-generation devices with superior clinical safety and efficacy profiles compared with bare-metal stents and first-generation drug-eluting stents. These design improvements and features are explored, and their resulting clinical safety and efficacy reviewed, focusing on platforms approved by the Food and Drug Administration currently widely used in the United States.

Contemporary Drug-Eluting Stent Platforms: Design, Safety, and Clinical Efficacy

First-generation drug-eluting stents significantly improved treatment of coronary disease, decreasing rates of revascularization. This was offset by high rates of late adverse events, driven primarily by stent thrombosis. Research and design improvements of individual DES platform components led to next-generation devices with superior clinical safety and efficacy profiles compared with bare-metal stents and first-generation drug-eluting stents. These design improvements and features are explored, and their resulting clinical safety and efficacy reviewed, focusing on platforms approved by the Food and Drug Administration currently widely used in the United States.

Propensity-Score Matched Comparison of Midterm Angiographic Outcomes of Sirolimus- Versus Everolimus- and Biolimus-Eluting Stents for De Novo Coronary Stenosis

We conducted propensity-score matched comparisons of midterm angiographic outcomes of sirolimus (SES) versus either everolimus- (EES) or biolimus- (BES) eluting stents after placements for coronary stenosis in a daily practice environment since previous randomized trials did not demonstrate the superiority of EES and BES over SES in terms of midterm angiographic outcomes.The present study was a non-randomized, retrospective, and lesion-based study, recruiting angiographically followed-up lesions within 550 days after successful and elective SES (n = 1793), EES (n = 1303), or BES (n = 324) placement for de novo native coronary stenosis during the period from August 2004 to January 2014 at 6 institutes. The endpoint, as an angiographic surrogate marker of clinical efficacy, was the distribution of in-stent follow-up percent diameter stenosis (%DS) which comprised the percentages of 1) follow-up %DS < 20 and 2) follow-up %DS > 50. Propensityscore matched analyses were conducted to adjust 21 baselines.In 1215 baseline adjusted lesions, the endpoints in the EES group [1) 74.1%, and 2) 4.6%] were significantly different from those in the SES group [57.9%; P < 0.001, 7.2%; P = 0.006, respectively). In 307 baseline adjusted lesions, the endpoints in the BES group [1) 80.5%, 2) 2.0%] were significantly different from those in the SES group [59.3%; P < 0.001, 2) 8.1%; P = 0.001, respectively].The present study is the first to confirm the superiority of midterm angiographic outcomes after the placement of EES and BES over SES for de novo coronary stenosis in a clinical setting.

Second-generation versus first-generation drug-eluting stents in patients with and without diabetes mellitus: pooled analysis from the RESET and NEXT trials

The impact of second-generation drug-eluting stent (G2-DES) implantations compared with first-generation drug-eluting stents (G1-DES) implantations on long-term clinical outcomes after percutaneous coronary intervention in patients with and without diabetes mellitus (DM) has not yet been adequately assessed. This pooled analysis compared 3-year clinical outcomes between G1- and G2-DES according to the presence or absence of DM, using individual patient-level data from the RESET and NEXT trials. Among 6431 patients, G1-DES and G2-DES were used in 713 and 2211 patients, respectively, in the DM stratum, and 887 and 2620 patients, respectively, in the non-DM stratum. Cumulative incidence of and adjusted hazard ratio (HR) for target-lesion revascularization (TLR) were not significantly different between G2- and G1-DES in both strata [DM, 8.7 versus 10.1%, adjusted HR: 0.80, 95% confidence interval (CI) 0.59-1.10, P = 0.17; non-DM, 5.7 versus 6.2%, adjusted HR: 0.86, 95% CI 0.62-1.22, P = 0.38]. In the insulin-treated DM (ITDM), G2-DES had a significantly lower adjusted HR for TLR compared with G1-DES, although there was no significant difference in the non-ITDM (ITDM, adjusted HR: 0.54, 95% CI 0.32-0.96, P = 0.04; non-ITDM, adjusted HR: 0.95, 95% CI 0.66-1.42, P = 0.81). G2-DES provided similar risk for TLR in non-ITDM and non-DM patients compared with G1-DES. However, G2-DES compared with G1-DES had a lower risk for TLR among ITDM patients.

Drug eluting stents: To evolve or dissolve?

Currently, percutaneous coronary intervention (PCI) with drug-eluting stents (DES) is the most commonly employed modality in the treatment of patients with coronary artery disease. PCI has come of age over the last four decades with enormous forays in the technology and drugs which have greatly enhanced its capability. Angioplasty and bare metal stents were plagued by high failure rates on account of restenosis leading to repeat revascularization procedures. Insights into pathophysiology of instent restenosis (ISR) and neointimal hyperplasia triggered the development of DES. The dreamlike remarkable reduction in ISR with DES was enthusiastically welcomed. Soon thereafter emerged the spectre of very late stent thrombosis (VLST) with DES. VLST was a new entity seen predominantly with DES and pathological insights as to the cause was instrumental in the development and efficacy of new generation DES. This review will highlight the evolution and present day DES for coronary interventions.

Long-term performance of the second-generation cobalt-chromium sirolimus-eluting stents in real-world clinical practice: 3-year clinical outcomes from the prospective multicenter FOCUS registry

BACKGROUND

The short- and mid-term outcomes of the second-generation cobalt-chromium sirolimus-eluting stent (CoCr-SES) in real-world patients had been reported previously, but the long-term performance remained unclear. The objective of this analysis was to evaluate the long-term safety and efficacy of the second-generation CoCr-SES from the FOCUS registry.

METHODS

The FOCUS registry (ClinicalTrials.gov Identifier: NCT00868829) enrolled all-comers eligible to receive Firebird-2 CoCr-SES. Follow-up was continued to 3 years to evaluate long-term safety and effectiveness of the second-generation CoCr-SES in real-world practice. Results of the extended-use group and standard-use group are compared to explore performance of CoCr-SES in more severe patients with more complex lesions.

RESULTS

The rate of 3-year MACE was 7.37%, consisting of 84 cases (1.78%) of cardiac death, 166 cases (3.52%) of MI and 98 cases (2.08%) of TVR. ARC definite/probable stent thrombosis happened in 34 (0.72%) patients, only 3 new cases (<0.1%) of very late stent thrombosis was reported in the third year. Meanwhile, the difference of MACE (7.77% vs. 6.06%; P=0.058), TLF (4.71% vs. 3.49%; P=0.085) and ARC definite/probable stent thrombosis (0.83% vs. 0.37%; P=0.116) between extended-use group and standard-use group showed no significance.

CONCLUSIONS

The second-generation CoCr-SES was associated with continued low rates of 3-year MACE, TLF and stent thrombosis in a broad spectrum of patients.

Final 3-Year Outcome of a Randomized Trial Comparing Second-Generation Drug-Eluting Stents Using Either Biodegradable Polymer or Durable Polymer: NOBORI Biolimus-Eluting Versus XIENCE/PROMUS Everolimus-Eluting Stent Trial

BACKGROUND

There is a paucity of data reporting the clinical outcomes of biodegradable polymer biolimus-eluting stent (BP-BES) compared with durable polymer everolimus-eluting stent (DP-EES) beyond 1 year after stent implantation when the polymer is fully degraded.

METHODS AND RESULTS

The NOBORI Biolimus-Eluting Versus XIENCE/PROMUS Everolimus-Eluting Stent Trial (NEXT) is a prospective, multicenter, randomized, open-label, noninferiority trial comparing BP-BES with DP-EES in patients scheduled for percutaneous coronary intervention using drug-eluting stent (DES) without any exclusion criteria among 98 participating centers in Japan. The trial was designed to evaluate noninferiority of BP-BES relative to DP-EES in terms of any target-lesion revascularization at 1 year and death or myocardial infarction at 3 years. Between May and October 2011, 3235 patients were randomly assigned to receive either BP-BES (1617 patients) or DP-EES (1618 patients). Complete 3-year follow-up was achieved in 97.6% of patients. At 3 years, the primary safety end point of death or myocardial infarction occurred in 159 patients (9.9%) in the BP-BES group and in 166 patients (10.3%) in the DP-EES group, demonstrating noninferiority of BP-BES relative to DP-EES (P noninferiority<0.0001 and P superiority=0.7). Cumulative incidence of target-lesion revascularization was not significantly different between the 2 groups (7.4% versus 7.1%; P=0.8). By a landmark analysis at 1 year, the cumulative incidences of death or myocardial infarction and target-lesion revascularization were also not significantly different between the 2 groups (4.6% versus 5.2%; P=0.46 and 3.3% versus 2.7%; P=0.39, respectively).

CONCLUSIONS

Safety and efficacy outcomes of BP-BES were non inferior to those of DP-EES 3 years after stent implantation.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01303640.

First-Generation Versus Second-Generation Drug-Eluting Stents in Coronary Chronic Total Occlusions: Two-Year Results of a Multicenter Registry

BACKGROUND

Limited data are available regarding the long-term clinical outcomes of second-generation drug-eluting stents (DES) versus first-generation DES in patients with coronary chronic total occlusion (CTO) who undergo percutaneous coronary intervention (PCI). The aim of this study was to compare the clinical outcomes of second-generation DES with those of first-generation DES for the treatment of CTO.

METHODS AND RESULTS

Between March 2003 and February 2012, 1,006 consecutive patients with CTO who underwent successful PCI using either first-generation DES (n = 557) or second-generation DES (n = 449) were enrolled in a multicenter, observational registry. Propensity-score matching was also performed. The primary outcome was cardiac death over a 2-year follow-up period. No significant differences were observed between the two groups regarding the incidence of cardiac death (first-generation DES versus second-generation DES; 2.5% vs 2.0%; hazard ratio [HR]: 0.86; 95% confidence interval [CI]: 0.37 to 1.98; p = 0.72) or major adverse cardiac events (MACE, 11.8% vs 11.4%; HR: 1.00; 95% CI: 0.67 to 1.50; p = 0.99). After propensity score matching, the incidences of cardiac death (HR: 0.86; 95% CI: 0.35 to 2.06; p = 0.86) and MACE (HR: 0.93; 95% CI: 0.63 to 1.37; p = 0.71) were still similar in both groups. Furthermore, no significant differences were observed between sirolimus-eluting, paclitaxel-eluting, zotarolimus-eluting, and everolimus-eluting stents regarding the incidence of cardiac death or MACE.

CONCLUSION

This study shows that the efficacy of second-generation DES is comparable to that of first-generation DES for treatment of CTO over 2 years of follow-up.

Impact of stent platform on longitudinal stent deformation: an in vivo frequency domain optical coherence tomography study

Recently, longitudinal coronary stent deformation has been highlighted as a possible cause of drug-eluting stent failure. Although bench tests and in vivo studies have demonstrated difference in longitudinal stent strength among the stents with different platforms, its clinical impact is still unknown. Furthermore, it is unknown if modified stent platform favorably affect the incidence of stent deformation. The aim of this study was to investigate the longitudinal deformation of the everolimus-eluting stents (EES) with different stent platforms by using frequency domain optical coherence tomography (FD-OCT). Seventy-eight lesions treated with EES (Xience Prime: n = 26, Promus element: n = 29, Promus premier: n = 23) were studied. After successful stent implantation, FD-OCT was performed and stent length was measured using three-dimensional reconstruction of the images in vivo. Percent longitudinal stent shortening (%SS) was defined as the in vivo stent length divided by nominal stent length. Longitudinal stent deformation was defined as  %SS > 10 %. Patients' and procedural characteristics were similar among 3 EESs. There was no difference in mean  %SS between Xience Prime, Promus Element and Promus Premier (1.0 ± 5.8, 2.9 ± 6.7 and 0.8 ± 3.7 %, p = 0.322). Incidence of the longitudinal stent deformation was significantly higher in Promus Element than the other stents (0, 13.8 and 0 %, p = 0.028). Incidence of longitudinal stent deformation was different between EESs with different stent platforms. Stent material, stent design and/or stent delivery balloon may affect longitudinal stent deformation.

Atherectomy Devices for the Treatment of Calcified Coronary Lesions

The presence of moderate and severe coronary artery calcification (CAC) is associated with higher rates of angiographic complications during percutaneous coronary intervention (PCI), as well as higher major adverse cardiac events compared with noncalcified lesions. Diabetes mellitus, a risk factor for CAC, is increasing in the United States. Vessel preparation before PCI with atherectomy can facilitate successful stent delivery and expansion that may otherwise not be possible. We review here CAC prevalence, risk factors, and impact on PCI, as well as the currently available coronary atherectomy devices including rotational atherectomy, orbital atherectomy, and laser atherectomy.

Three-Year Clinical and Angiographic Outcomes After Everolimus-Eluting Stent Implantation in Patients With a History of Coronary Artery Bypass Grafting

The clinical and angiographic outcomes after percutaneous coronary intervention (PCI) with everolimus-eluting stent (EES) implantation in patients with a history of coronary artery bypass grafting (CABG) have yet to be fully investigated. The aim of the present study was to investigate 3-year clinical outcomes after EES implantation in patients with a history of CABG.We retrospectively enrolled 176 consecutive patients who had undergone EES implantation. Three-year clinical follow-up data were obtained from all patients. Follow-up angiograms and serial quantitative coronary angiography analysis (QCA) were performed for 139 (79.0%) patients. Patients from the prior CABG (+) group (n = 17; 9.7%) had higher incidences of target lesion revascularization (TLR; 41.2% versus 3.8%, P < 0.001) and major adverse cardiac events (47.1% versus 15.1%, P = 0.004). A landmark analysis conducted 1 year into our study showed a higher incidence of TLR in the prior CABG (+) group (20.0% versus 3.0%, P = 0.017).The reason for EES implantation in the prior CABG (+) group was saphenous vein graft (SVG) failure in 19 (79.2%) lesions, although the target vessel was the SVG in 8 (33.3%) lesions. There were no significant differences in clinical and follow-up QCA data between the native vessel and SVG PCI groups.This study revealed that a history of CABG was a risk factor for TLR after EES implantation. The major reason for PCI after CABG was SVG failure; both native vessel and SVG PCI showed poor outcomes. Further investigations may be warranted to determine which interventions are most effective in this high-risk subset.

Insulin Resistance as a Predictor of the Late Catch-up Phenomenon After Drug-Eluting Stent Implantation

BACKGROUND

Percutaneous coronary intervention (PCI) is an effective treatment for patients with ischemic heart disease. In particular, restenosis is suppressed after drug-eluting stent (DES) implantation. However, several problems remain. Previously, we reported neointimal proliferation after DES implantation, which was associated with insulin resistance (IR). The aim of the present study was to clarify whether IR is associated with mortality and major adverse cardiac and cerebrovascular events (MACCE) after 1st-generation DES implantation.

METHODS AND RESULTS

We researched the clinical records of 109 patients who had undergone elective PCI and DES implantation between May 2007 and December 2010. We segregated these patients according to the value of the homeostasis model assessment of IR (HOMA-IR) into Group P (n=63; HOMA-IR ≥2.5, positive) and Group N (n=46; HOMA-IR <2.5, negative), and examined the relationship between HOMA-IR and MACCE. The observation period was 7.4±1.6 years. There were no differences between the 2 groups in the occurrence of all-cause death, cardiac death, restenosis, myocardial infarction, stroke, heart failure, or stent thrombosis. However, the late catch-up phenomenon was significantly more common in Group P than in Group N (12.7% vs. 2.2% P=0.048).

CONCLUSIONS

IR is a useful predictor of the late catch-up phenomenon after DES implantation, and improvement of IR may help to prevent the phenomenon. (Circ J 2016; 80: 657-662).

Optical frequency domain imaging vs. intravascular ultrasound in percutaneous coronary intervention (OPINION trial): Study protocol for a randomized controlled trial

BACKGROUND

Optical coherence tomography is becoming increasingly widespread as an adjunctive intravascular diagnostic technique in percutaneous coronary intervention (PCI), because of its ability to visualize coronary structures at high resolution. Several studies have reported that intravascular ultrasound (IVUS) guidance in PCI might be helpful to reduce subsequent stent thrombosis, restenosis, repeat revascularization, myocardial infarction, and cardiac death. The OPtical frequency domain imaging vs. INtravascular ultrasound in percutaneous coronary InterventiON (OPINION) trial is aimed at evaluating the impact of optical frequency domain imaging (OFDI) guidance in PCI on clinical outcomes compared with IVUS guidance.

METHODS AND DESIGN

The OPINION trial is a multicenter, prospective, randomized, controlled, open-label, parallel group, non-inferiority trial in Japan. The eligible patients are randomly assigned to receive either OFDI-guided PCI or IVUS-guided PCI. PCI is performed using the biolimus-eluting stent in accordance with a certain criteria of OFDI and IVUS for optimal stent deployment. All patients will undergo a follow-up angiography at 8 months. The primary endpoint is target vessel failure composed of cardiac death, myocardial infarction attributed to the target vessel, and clinically-driven target vessel revascularization at 12 months.

CONCLUSION

When completed, the OPINION trial will contribute to define the clinical value of the OFDI guidance in PCI.

Drug-eluting stents: the past, present, and future

Since the advent of percutaneous coronary intervention, enormous advances have been made in the treatment of coronary artery disease. Angioplasty and bare metal stents were plagued by high rates of restenosis leading to repeat revascularization procedures. Examination of the underlying pathophysiology of restenosis led to the development of drug-eluting stents to reduce neointimal hyperplasia. However, as restenosis rates declined, length of dual antiplatelet therapy use and risk of long-term stent thrombosis associated with drug-eluting stents increased. Subsequent generations have improved each facet of stent design. Novel alloys maintain durability and reduce strut thickness to increase deliverability, biocompatible polymers decrease the inflammatory response and improve drug elution kinetics, and new generations of drugs predictably inhibit restenosis. Developments on the horizon include stents with bioabsorbable polymers and platforms. The purpose of this review is to assess the evolution of stent design and the evidence behind each generation and to peer into the future of stent technology.

One-year outcome of a prospective trial stopping dual antiplatelet therapy at 3 months after everolimus-eluting cobalt-chromium stent implantation: ShortT and OPtimal duration of Dual AntiPlatelet Therapy after everolimus-eluting cobalt-chromium stent (STOPDAPT) trial

There has been no previous prospective study evaluating dual antiplatelet therapy (DAPT) duration shorter than 6 months after cobalt-chromium everolimus-eluting stent (CoCr-EES) implantation. STOPDAPT trial is a prospective multi-center single-arm study evaluating 3-month DAPT duration after CoCr-EES implantation. The primary endpoint was a composite of cardiovascular death, myocardial infarction (MI), stroke, definite stent thrombosis (ST) and TIMI major/minor bleeding at 1 year. Between September 2012 and October 2013, a total of 1525 patients were enrolled from 58 Japanese centers, with complete 1-year follow-up in 1519 patients (99.6 %). Thienopyridine was discontinued within 4 months in 1444 patients (94.7 %). The event rates beyond 3 months were very low (cardiovascular death: 0.5 %, MI: 0.1 %, ST: 0 %, stroke: 0.7 %, and TIMI major/minor bleeding: 0.8 %). Cumulative 1-year incidence of the primary endpoint was 2.8 % [upper 97.5 % confidence interval (CI) 3.6 %], which was lower than the pre-defined performance goal of 6.6 % (P < 0.0001). Using the CoCr-EES group in the RESET trial as a historical comparison group, where nearly 90 % of patients had continued DAPT at 1 year, cumulative incidence of the primary endpoint tended to be lower in the STOPDAPT than in the RESET (2.8 versus 4.0 %, P = 0.06) and adjusted hazard ratio was 0.64 (95 % CI 0.42–0.95, P = 0.03). The cumulative incidence of definite/probable ST was lower in the STOPDAPT than in the RESET [0 patient (0 %) versus 5 patients (0.3 %), P = 0.03]. In conclusion, stopping DAPT at 3 months in selected patients after CoCr-EES implantation was at least as safe as the prolonged DAPT regimen adopted in the historical control group.

Intravascular Ultrasound and Angiographic Predictors of In-Stent Restenosis of Chronic Total Occlusion Lesions

Despite the benefits of successful percutaneous coronary interventions (PCIs) for chronic total occlusion (CTO) lesions, PCIs of CTO lesions still carry a high rate of adverse events, including in-stent restenosis (ISR). Because previous reports have not specifically investigated the intravascular ultrasound (IVUS) predictors of ISR in CTO lesions, we focused on these predictors. We included 126 patients who underwent successful PCIs, using drug-eluting stents, and post-PCI IVUS of CTO lesions. Patient and lesion characteristics were analyzed to elucidate the ISR predictors. In each lesion, an average of 1.7 ± 0.7 (mean length, 46.4 ± 20.3 mm) stents were used. At 9 months follow-up, 14 (11%) patients demonstrated ISR, and 8 (6.3%) underwent target lesion revascularization. Multivariate logistic regression analysis showed that the independent predictors of ISR were the post-PCI minimal luminal diameter (MLD) and the stent expansion ratio (SER; minimal stent cross-sectional area (CSA) over the nominal CSA of the implanted stent), measured using quantitative coronary angiography (QCA) and IVUS, respectively. A receiver operating characteristic analysis indicated that the best post-PCI MLD and SER cut-off values for predicting ISR were 2.4 mm (area under the curve [AUC], 0.762; 95% confidence interval (CI), 0.639–0.885) and 70% (AUC, 0.714; 95% CI, 0.577–0.852), respectively. Lesions with post-PCI MLD and SER values less than these threshold values were at a higher risk of ISR, with an odds ratio of 23.3 (95% CI, 2.74–198.08), compared with lesions having larger MLD and SER values. Thus, the potential predictors of ISR, after PCI of CTO lesions, are the post-PCI MLD and SER values. The ISR rate was highest in lesions with a post-PCI MLD ≤2.4 mm and an SER ≤70%.

Impact of technological developments in drug-eluting stents on patient-focused outcomes: a pooled direct and indirect comparison of randomised trials comparing first- and second-generation drug-eluting stents

AIMS

To establish whether technological improvements in drug-eluting stent (DES) technology introduced in second-generation (G2) DES have contributed to improving patient-focused outcomes.

METHODS AND RESULTS

We performed a systematic review of randomised clinical trials (RCT) comparing first-generation (G1) and G2 DES with a>9-month clinical follow-up. The primary endpoint for efficacy was ischaemia-driven target lesion revascularisation (ID-TLR); safety endpoints were all-cause death, myocardial infarction (MI) and stent thrombosis (ST). Sixteen RCTs involving 25,427 patients met eligibility criteria (17 comparisons). In these trials, paclitaxel (PES) and sirolimus (SES) were compared with everolimus (EES), zotarolimus (ZES) or biolimus A9 (BES) DES. G2 varied in metal alloy, strut thickness and type of drug-eluting matrix. Overall, G2 DES were associated with a 26% relative risk reduction (RRR) of MI (relative risk [RR]=0.74, 95% CI: 0.61-0.90, p=0.003) and ST (RR=0.70, 95% CI: 0.55-0.89, p=0.004), while no significant benefit was observed for ID-TLR and death. Use of 2G DES was associated with a significant reduction in the risk of ID-TLR (RR=0.66, 95% CI: 0.51-0.85, p=0.002), MI (RR=0.60, 95% CI: 0.49-0.72, p<0.001) and ST (RR=0.41, 95% CI: 0.26-0.65, p=0.001) when compared with PES. Strut thickness ≤91 µm in G2 DES was associated with a significantly lower risk of MI (RR=0.54, 95% CI: 0.51-0.86, p=0.002).

CONCLUSIONS

The introduction of thinner stent struts and other technological improvements made in G2 DES technology have translated into better patient outcomes. Overall, the net benefit of G2 DES over G1 DES is expressed in terms of ID-TLR and ST risk reduction but it could be masked by heterogeneities in the use of G1 comparators and the use of non-inferiority study designs in RCTs.

Meta-analysis of long-term clinical outcomes of everolimus-eluting stents

The superiority of everolimus-eluting stents (EES) over sirolimus-eluting stents (SES) for long-term clinical outcomes has not been yet firmly established. We conducted a systematic review and a meta-analysis of randomized controlled trials (RCTs) comparing EES directly with SES using the longest available follow-up data. We searched PubMed, the Cochrane database, and ClinicalTrials.gov for RCTs comparing outcomes between EES and SES and identified 13,434 randomly assigned patients from 14 RCTs. EES was associated with significantly lower risks than SES for definite stent thrombosis (ST), definite/probable ST, target-lesion revascularization (TLR), and major adverse cardiac events (MACE). The risks for all-cause death and myocardial infarction were similar between EES and SES. By the stratified analysis according to the timing after stent implantation, the favorable trend of EES relative to SES for ST, TLR, and MACE was consistently observed both within and beyond 1 year. The lower risk of EES relative to SES for MACE beyond 1 year was statistically significant (pooled odds ratio 0.77, 95% confidence interval 0.61 to 0.96, p = 0.02). In conclusion, the current meta-analysis of 14 RCTs directly comparing EES with SES suggested that EES provided improvement in both safety and efficacy; EES compared with SES was associated with significantly lower risk for definite ST, definite/probable ST, TLR, and MACE. The direction and magnitude of the effect beyond 1 year were comparable with those observed within 1 year.

Comparison of Five-Year Outcome of Percutaneous Coronary Intervention With Coronary Artery Bypass Grafting in Triple-Vessel Coronary Artery Disease (from the Coronary Revascularization Demonstrating Outcome Study in Kyoto PCI/CABG Registry Cohort-2)

Studies evaluating long-term (≥5 years) outcomes of percutaneous coronary intervention (PCI) using drug-eluting stents compared with coronary artery bypass grafting (CABG) in patients with triple-vessel coronary artery disease (TVD) are still limited. We identified 2,978 patients with TVD (PCI: n = 1,824, CABG: n = 1,154) of 15,939 patients with first coronary revascularization enrolled in the Coronary Revascularization Demonstrating Outcome Study in Kyoto PCI/CABG Registry Cohort-2. The primary outcome measure in the present analysis was a composite of death, myocardial infarction (MI), and stroke. Median follow-up duration for the surviving patients was 1,973 days (interquartile range 1,700 to 2,244). The cumulative 5-year incidence of death/MI/stroke was significantly higher in the PCI group than in the CABG group (28.2% vs 24.0%, log-rank p = 0.006). After adjusting for confounders, the excess risk of PCI relative to CABG for death/MI/stroke remained significant (hazard ratio [HR] 1.38, 95% confidence interval [CI] 1.13 to 1.68, p = 0.002). The excess risks of PCI relative to CABG for all-cause death, MI, and any coronary revascularization were also significant (HR 1.38, 95% CI 1.10 to 1.74, p = 0.006; HR 2.81, 95% CI 1.69 to 4.66, p <0.001; and HR 4.10, 95% CI 3.32 to 5.06, p <0.001, respectively). The risk for stroke was not significantly different between the PCI and CABG groups (HR 0.88, 95% CI 0.61 to 1.26, p = 0.48). There were no interactions for the primary outcome measure between the mode of revascularization (PCI or CABG) and the subgroup factors such as age, diabetes, and Synergy Between PCI With Taxus and Cardiac Surgery score. In conclusion, CABG compared with PCI was associated with better long-term outcome in patients with TVD.

Antiplatelet therapy discontinuation and the risk of serious cardiovascular events after coronary stenting: observations from the CREDO-Kyoto Registry Cohort-2

Relation of antiplatelet therapy (APT) discontinuation with the risk of serious cardiovascular events has not been fully addressed yet. This study is aimed to evaluate the risk of ischemic event after APT discontinuation based on long-term APT status of large cohort. In the CREDO-Kyoto Registry Cohort-2 enrolling 15939 consecutive patients undergoing first coronary revascularization, 10470 patients underwent percutaneous coronary intervention either with bare-metal stents (BMS) only (N=5392) or sirolimus-eluting stents (SES) only (N=5078). Proportions of patients taking dual-APT were 67.3% versus 33.4% at 1-year, and 48.7% versus 24.3% at 5-year in the SES and BMS strata, respectively. We evaluated daily APT status (dual-, single- and no-APT) and linked the adverse events to the APT status just 1-day before the events. No-APT as compared with dual- or single-APT was associated with significantly higher risk for stent thrombosis (ST) beyond 1-month after SES implantation (cumulative incidence rates beyond 1-month: 1.23 versus 0.15/0.29, P<0.001/P<0.001), while higher risk of no-APT for ST was evident only until 6-month after BMS implantation (incidence rates between 1- and 6-month: 8.43 versus 0.71/1.20, P<0.001/P<0.001, and cumulative incidence rates beyond 6-month: 0.31 versus 0.11/0.08, P=0.16/P=0.08). No-APT as compared with dual- or single-APT was also associated with significantly higher risk for spontaneous myocardial infarction (MI) and stroke regardless of the types of stents implanted. Single-APT as compared with dual-APT was not associated with higher risk for serious adverse events, except for the marginally higher risk for ST in the SES stratum. In conclusion, discontinuation of both aspirin and thienopyridines was associated with increased risk for serious cardiovascular events including ST, spontaneous MI and stroke beyond 1-month after coronary stenting.

Clinical outcomes in low risk coronary artery disease patients treated with different limus-based drug-eluting stents--a nationwide retrospective cohort study using insurance claims database

The clinical outcomes of different limus-based drug-eluting stents (DES) in a real-world setting have not been well defined. The aim of this study was to investigate the clinical outcomes of three different limus-based DES, namely sirolimus-eluting stent (SES), Endeavor zotarolimus-eluting stent (E-ZES) and everolimus-eluting stent (EES), using a national insurance claims database. We identified all patients who received implantation of single SES, E-ZES or EES between January 1, 2007 and December 31, 2009 from the National Health Insurance claims database, Taiwan. Follow-up was through December 31, 2011 for all selected clinical outcomes. The primary end-point was all-cause mortality. Secondary end-points included acute coronary events, heart failure needing hospitalization, and cerebrovascular disease. Cox regression model adjusting for baseline characteristics was used to compare the relative risks of different outcomes among the three different limus-based DES. Totally, 6584 patients were evaluated (n=2142 for SES, n=3445 for E-ZES, and n=997 for EES). After adjusting for baseline characteristics, we found no statistically significant difference in the risk of all-cause mortality in three DES groups (adjusted hazard ratio [HR]: 1.14, 95% confidence interval [CI]: 0.94-1.38, p=0.20 in E-ZES group compared with SES group; adjusted HR: 0.77, 95% CI: 0.54-1.10, p=0.15 in EES group compared with SES group). Similarly, we found no difference in the three stent groups in risks of acute coronary events, heart failure needing hospitalization, and cerebrovascular disease. In conclusion, we observed no difference in all-cause mortality, acute coronary events, heart failure needing hospitalization, and cerebrovascular disease in patients treated with SES, E-ZES, and EES in a real-world population-based setting in Taiwan.

Balancing the risks of bleeding and stent thrombosis: a decision analytic model to compare durations of dual antiplatelet therapy after drug-eluting stents

BACKGROUND

After coronary stent placement, whether dual antiplatelet therapy (DAPT) duration should be extended to prevent late stent thrombosis (ST) or adverse cardiovascular events is uncertain.

METHODS

To define the reduction in ischemic events required to outweigh increased bleeding with longer-duration DAPT, we developed a decision-analytic Markov model comparing DAPT durations of 6, 12, and 30 months after DES. Separate models were developed for patients presenting with and without an acute coronary syndrome (ACS). We used sensitivity analyses to identify the incremental benefit of longer-duration DAPT on either ST or the composite of cardiac death, myocardial infarction, and ischemic stroke (major adverse cardiovascular and cerebrovascular events [MACCEs]) required to outweigh the increased risk of bleeding associated with longer DAPT. The outcome from each strategy was quantified in terms of quality-adjusted life years.

RESULTS

In the non-ACS population, in order for 30 months of DAPT to be preferred over 12 months of therapy, DAPT would have to result in a 78% reduction in the risk of ST (relative risk [RR] 0.22, 3.1 fewer events per 1000) and only a 5% reduction in MACCE (RR 0.95, 2.2 fewer events per 1000) as compared with aspirin alone. For the ACS population, DAPT would have to result in a 44% reduction in the risk of ST (RR 0.56, 3.4 fewer events per 1000) but only a 2% reduction in MACCE (RR 0.98, 2.3 fewer events per 1000) as compared with aspirin alone, for 30 months of DAPT to be preferred for 12 months.

CONCLUSIONS

Small absolute differences in the risk of ischemic events with longer DAPT would be sufficient to outweigh the known bleeding risks.

Regulation of CD4 T-cell differentiation and inflammation by repressive histone methylation

Repressive epigenetic modifications such as dimethylation and trimethylation histone H3 at lysine 9 (H3K9me2 and H3K9me3) and H3K27me3 have been shown to be critical for embryonic stem (ES) cell differentiation by silencing cell lineage-promiscuous genes. CD4(+) T helper (T(H)) cell differentiation is a powerful model to study the molecular mechanisms associated with cellular lineage choice in adult cells. Naïve T(H) cells have the capacity to differentiate into one of the several phenotypically and functionally distinct and stable lineages. Although some repressive epigenetic mechanisms have a critical role in T(H) cell differentiation in a similar manner to that in ES cells, it is clear that there are disparate functions for certain modifications between ES cells and T(H) cells. Here we review the role of repressive histone modifications in the differentiation and function of T(H) cells in health and disease.

First-generation versus second-generation drug-eluting stents in current clinical practice: updated evidence from a comprehensive meta-analysis of randomised clinical trials comprising 31 379 patients

Background

First-generation drug-eluting stents (DES) have become the most widely used devices worldwide for management of coronary artery disease. As remote follow-up data were becoming available, concerns emerged in regard to their long-term safety. Second-generation DES were designed to overcome safety issues, but the results of randomised clinical trials remain conflicting.

Methods

We compared the safety and efficacy of first-generation versus second-generation Food and Drug Administration approved DES; the following devices were included: first-generation sirolimus-eluting stent (SES) and paclitaxel-eluting stents (PES); second-generation everolimus-eluting stent (EES), zotarolimus-eluting stent Endeavor and ZES-Resolute (ZES-R). Prespecified safety end points comprised ≤1 and >1 year: overall and cardiac mortality, myocardial infarction (MI), definite/definite or probable ST; efficacy end points were target lesion revascularisation and target vessel revascularisation. Composite end points were analysed as well.

Results

33 randomised controlled trials involving 31 379 patients with stable coronary artery disease or acute coronary syndrome undergoing DES implantation were retrieved. No differences in mortality among devices were found. In the overall class comparison, second-generation DES were associated with a 22% reduction of odds of MI at short-term OR 0.77 (95% CI 0.68 to 0.89) p=0.0002; EES reduced the odds of definite-probable ST compared with PES: OR 0.33 (95% CI 0.15 to 0.73) p=0.006; First-generation SES along with second-generation EES and ZES-R showed similar efficacy in decreasing the odds of repeat revascularisation.

Conclusions

Second-generation EES and ZES-R offer similar levels of efficacy compared with first-generation SES, but are more effective than PES; however, only second-generation EES significantly reduced the incidence of MI and ST, and therefore should be perceived as the safest DES to date.

Vascular response to drug-eluting stent with biodegradable vs. durable polymer. Optical coherence tomography substudy of the NEXT

BACKGROUND

The aim of the present study was to compare vascular healing response between everolimus-eluting stent (EES) and biolimus-eluting stent (BES) using optical coherence tomography (OCT).

METHODS AND RESULTS

In the NOBORI Biolimus-Eluting Versus XIENCE V/PROMUS Everolimus-Eluting Stent Trial (NEXT), a formal OCT substudy investigated 91 patients (55 EES-treated lesions in 48 patients and 51 BES-treated lesions in 43 patients) with 8-12 months follow-up imaging at 18 centers. A total of 980 frames with 8,996 struts in EES and 907 frames with 8,745 struts in BES were analyzed. Mean neointima thickness in EES and BES was 105±82μm and 91±80μm, respectively (P<0.001). With regard to stent-treated lesions, the percentage of struts not covered by neointima (3±7% vs. 9±10%, P<0.001) and the frequency of stent-treated lesions with any uncovered struts (n=28, 51% vs. n=42, 82%; P<0.001) were significantly lower in EES compared with BES. In addition, the percentage of malapposed struts (0.2±0.8% vs. 1.3±2.8%, P=0.006) and the frequency of stent-treated lesions with any malapposed struts (n=6, 11% vs. n=14, 27%; P=0.028) were significantly lower in EES compared with BES.

CONCLUSIONS

Incomplete vascular healing characterized by the presence of struts not covered by neointima and malapposed struts was less common in EES compared with BES.

Novel drug-eluting stents for coronary revascularization

Over the past decades, there has been significant evolution in coronary stents used in percutaneous coronary intervention. The current novel drug-eluting stents available in the United States represent significant advancements compared to angioplasty, bare-metal stents, and the first generation of drug-eluting stents (DES). The Xience everolimus-eluting stents, Promus everolimus-eluting stents, and Resolute zotarolimus-eluting stents currently demonstrate the optimal balance of safety and efficacy. Endeavor zotarolimus-eluting stents have shorter drug-elution courses, and recent evidence suggests that 3 months of dual antiplatelet therapy appears safe, making Endeavor preferred when early discontinuation of dual antiplatelet therapy is warranted. Despite these advances in stent design, the permanent polymer and metallic stent remain in the vessel wall and may precipitate sustained inflammation, persistent vasomotor dysfunction, and in-stent neo-atherosclerosis. Bioresorbable platforms with biodegradable polymers have been developed to overcome the aforementioned limitations, and the outcomes of ongoing clinical trials are eagerly anticipated to determine if these novel stents will further improve clinical outcomes.

Update on interventional cardiology

This article provides a detailed review of the most important studies on interventional cardiology reported in publications or presentations during the year 2012. With regard to coronary interventions, ST-elevation myocardial infarction is extensively addressed in studies focusing on the relevance of reducing the reperfusion time and the utility of various devices and pharmacological strategies in primary angioplasty. Multiple comparative studies involving different generations of drug-eluting stents are available and indicate a favorable progression in terms of safety and efficacy. The risk of late thrombosis with the new generations of drug-eluting stents seems to be equivalent to that observed with bare-metal stents. The clinical outcomes with these stents in the elderly, in left main coronary artery, or in multivessel disease have also been the subject of important trials. Among the studies on intracoronary diagnostic techniques, those correlating imaging and pressure-based techniques are of special interest. The percutaneous treatment of structural heart disease, particularly transcatheter aortic valve implantation, followed by mitral repair, continues to be the subject of a great number of publications. Finally, renal denervation is currently being widely discussed in the literature.