Dual Antiplatelet Therapy Duration and Clinical Outcomes Following Treatment With Zotarolimus-Eluting Stents

Prospective multicentre open-label randomised controlled trial of 3-month versus 12-month dual antiplatelet therapy after implantation of the new generation biodegradable polymer sirolimus TARGET-eluting coronary stent: protocol of the TARGET DAPT trial

INTRODUCTION

Dual antiplatelet therapy (DAPT) with aspirin and thienopyridine is required after placement of coronary stents to prevent thrombotic complications. However, current recommendation for duration of DAPT remains controversial. Firehawk is a biodegradable polymer applied to recessed abluminal grooves, sirolimus target-eluting stent associated with early excellent healing response and almost complete strut coverage, as well as possibly reduced myocardial ischaemic events. But the optimal DAPT duration for such a new generation stent is less known. Therefore, the present trial seeks to evaluate the safety and efficacy of 3-month versus 12-month DAPT in broad patients receiving Firehawk stents.

METHODS AND ANALYSIS

The TARGET DAPT study is designed to access the benefits and risks of short-term (3 months) versus long-term (12 months) DAPT in preventing stent thrombosis or major adverse cardiovascular and cerebrovascular events in subjects undergoing percutaneous coronary intervention for the treatment of coronary artery obstructive lesions. The TARGET DAPT trial is a large, prospective, multicentre, randomised (1:1) non-inferiority clinical trial that will enrol 2446 subjects treated with Firehawk stents. The primary endpoint is net adverse clinical and cerebral events, a composite of all-cause death, myocardial infarction, cerebral vascular accident and major bleeding (BARC 2,3 or 5) at 18 months clinical follow-up postindex procedure.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Ethics Committee of Zhongshan Hospital, Shanghai. The reference number is B2018-146R. Study findings will be made available to interested participants. Study results will be submitted for publication in a peer-reviewed journal. Also the protocol will be submitted and approved by the institutional Ethics Committee at each participating clinical centre.

TRIAL REGISTRATION

NCT03008083.

PIK3CG single nucleotide polymorphisms are associated with poor responsiveness to clopidogrel and increased risk of ischemia in patients with coronary heart disease

BACKGROUND

This study explores the associations between PIK3CG single nucleotide polymorphisms (SNPs, rs1129293 and rs17398575) and patient responsiveness to clopidogrel to evaluate the risks of ischemia in patients with coronary heart disease (CHD).

METHODS

The study consisted of 513 CHD patients who received clopidogrel as part of antiplatelet therapy, after percutaneous coronary intervention. According to the patient responsiveness to clopidogrel, the subjects were assigned to either clopidogrel-resistant (CR) or clopidogrel-sensitive (CS) groups. CR group was determined by patients' platelet aggregation rate of ≥70% and poor responsiveness to clopidogrel, and CS group by patients' platelet aggregation rates of <70% and good responsiveness to clopidogrel. Polymerase chain reaction using TaqMan probe was employed to detect PIK3CG polymorphism. Haplotype and linkage disequilibrium analyses were performed. Prognosis analysis was performed using the Kaplan-Meier curve.

RESULTS

Significant difference was found in genotype and rs1129293 and rs17398575 allele frequency between the CR and CS groups. Haplotype analysis indicated that the frequency of TG allele was higher in the CR group compared with the CS group, and the frequency of CA allele was lower in the CR group compared with the CS group. Patients with rs1129293 CT + TT genotype and T allele, rs1129293 AG + GG genotype and G allele exhibited an increased CR risk. Logistic regression analysis determined hypertension history as an independent risk factor for CR. The Kaplan-Meier curve suggests that distribution curve of cumulative probability nonischemic events was different between patients with rs1129293 and rs17398575 alleles. Stable CHD patients with TT genotype of rs1129293 allele and GG genotype of rs17398575 allele showed poorer prognosis compared to those with other genotypes and patients with acute coronary syndromes.

CONCLUSION

A positive correlation may exist between PIK3CG SNPs (rs1129293 and rs17398575) and patients with poor responsiveness to clopidogrel. These findings show that this factor may contribute to an increased risk of ischemia in patients suffering from CHD.

Should a prolonged duration of dual anti-platelet therapy be recommended to patients with diabetes mellitus following percutaneous coronary intervention? A systematic review and meta-analysis of 15 studies

Background

This study aimed to compare the adverse clinical outcomes associated with a short and a prolonged duration of Dual Anti-Platelet Therapy (DAPT) in patients with Diabetes Mellitus (DM) after undergoing Percutaneous Coronary Intervention (PCI).

Methods

Medline/PubMed, EMBASE and the Cochrane library were searched for studies comparing the short and prolonged DAPT use in patients with DM. Adverse outcomes were considered as the clinical endpoints in this analysis. Odds Ratios (OR) with 95 % Confidence Intervals (CI) were used to express the pooled effect on discontinuous variables and the pooled analyses were performed with RevMan 5.3.

Results

Fifteen studies with a total number of 25,742 patients with DM were included in this current analysis which showed no significant differences in primary endpoints, net clinical outcomes, myocardial infarction and stroke with OR: 1.03, 95 % CI: 0.65–1.64; P = 0.90, OR: 0.96, 95 % CI: 0.69–1.34; P = 0.81, OR: 0.85, 95 % CI: 0.70–1.04; P = 0.12 and OR: 0.94, 95 % CI: 0.65–1.36; P = 0.75 respectively. Revascularization was also similar between these 2 groups of patients with DM. However, even if mortality favored prolonged DAPT use, with OR: 0.87, 95 % CI: 0.76–1.00; P = 0.05, the result only approached significance. Also, stent thrombosis insignificantly favored a prolonged DAPT duration with OR: 0.56, 95 % CI: 0.27–1.17; P = 0.12. Thrombolysis In Myocardial Infarction (TIMI) defined major and minor bleeding were not significantly different in these diabetic patients with OR: 0.91, 95 % CI: 0.60–1.37; P = 0.65 and OR: 1.08, 95 % CI: 0.62–1.91; P = 0.78 respectively. However, bleeding defined by the Bleeding Academic Research Consortium (BARC) classification was significantly higher with a prolonged DAPT use in these diabetic patients with OR: 1.92, 95 % CI: 1.58–2.34; P < 0.00001.

Conclusion

Following PCI, a prolonged DAPT use was associated with similar adverse clinical outcomes but with a significantly increased BARC defined bleeding compared to a short term DAPT use in these patients with DM. However, even if mortality and stent thrombosis favored a prolonged DAPT use, these outcomes only either reached statistical significance or were insignificant respectively, showing that a clear decision about recommending a prolonged duration of DAPT to patients with DM might not be possible at this moment, warranting further research in this particular subgroup.

Optimal duration of dual antiplatelet therapy after drug-eluting stent implantation: a meta-analysis of 3 randomized controlled trials

PURPOSE

The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is still unclear. We conducted a meta-analysis of randomized trials to assess the optimal duration of DAPT after DES implantation.

METHODS

Articles were identified through a literature search of EMBASE, Pubmed, Europubmed, and the Cochrane Library until November 2013. Data were independently extracted by 2 reviewers. A random effect model was used to calculate the pooled odds ratios (ORs) with 95% confidence intervals (CIs) of the clinical outcomes concerned.

RESULTS

Three randomized controlled trials with zotarolimus- or everolimus-eluting stents and 6679 patients were included. There were no significant differences between short-term DAPT and standard-term DAPT in the comparison of incidences of cardiac death (OR, 0.84; 95% CI, 0.53-1.35; P = 0.48), myocardial infarction (OR, 1.21; 95% CI, 0.83-1.75; P = 0.32), stent thrombosis (OR, 1.30; 95% CI, 0.50-3.39; P = 0.59), and target vessel revascularization (OR, 1.16; 95% CI, 0.89-1.52; P = 0.26). Short-term DAPT did not increase the risk of all-cause death (OR, 0.86; 95% CI, 0.59-1.26; P = 0.44), cerebrovascular accidents (OR, 0.88; 95% CI, 0.421.81; P = 0.72), and major bleeding events (OR, 0.59; 95% CI, 0.30-1.15; P = 0.12).

CONCLUSIONS

The results indicate that short-term DAPT do not increase the risk of cardiac death, myocardial infarction, stent thrombosis, target vessel revascularization, major bleeding, cerebrovascular accidents, and all-cause death at 12 months after implantation of DES compared with current standard-term DAPT. However, only 3 studies with second generation of DES are included in this meta-analysis. Further well-designed studies are still needed.

Tradeoff between bleeding and stent thrombosis in different dual antiplatelet therapy regimes: Importance of case fatality rates and effective treatment durations

BACKGROUND

The tradeoff between stent thrombosis (ST) and major bleeding (MB) of 12- versus 6-month dual antiplatelet therapy (DAPT) after coronary stent implantation has not been clearly defined.

METHODS

Definite/probable ST and MB (TIMI major and Bleeding Academic Research Consortium (BARC) ≥ 3) were compared in 2 subsequent trials with similar inclusion criteria but different DAPT duration, that is, BASKET (6 months; n = 557) and BASKET-PROVE (12 months; n = 2,314), between months 0 to 6 (DAPT in both trials), 7 to 12 (DAPT in BASKET-PROVE only), and 13 to 24 (aspirin in both trials) using propensity score-adjusted, time-stratified Cox proportional hazard models.

RESULTS

Overall, event rates were low with fewer ST but similar MB in prolonged DAPT. Analysis of the 3 periods showed a uniform pattern for ST (interaction DAPT/period; P = .145) but an inconsistent pattern for MB (interaction DAPT/period; P < .001 for TIMI major and P = .046 for BARC ≥ 3), with more MB occurring during months 7 to 12 with prolonged DAPT. Considering observed case fatality rates of 31% with ST and 11% with MB, the extrapolated prevention of 27 ST deaths and the excess of 5 MB deaths resulted in an expected benefit of 22 survivors/10,000 patients treated over 2 years with prolonged DAPT.

CONCLUSION

Despite overall low event rates, prolonged DAPT was associated with more MB during months 7 to 12 according to the interaction DAPT/period. Given the higher observed case fatality rates of ST versus MB, 12- versus 6-month DAPT was associated with an extrapolated reduction in mortality. Effective treatment periods and case fatality rates seem important in the analysis of different DAPT durations, specifically with regard to ongoing trials.

Dual-antiplatelet treatment beyond 1 year after drug-eluting stent implantation (ARCTIC-Interruption): a randomised trial

BACKGROUND

Optimum duration of dual antiplatelet treatment (DAPT) after coronary stenting remains uncertain, with an unknown efficacy to safety ratio of extended treatment leading to discrepancies between international guidelines and clinical practice. We assessed whether DAPT continuation beyond 1 year after coronary stenting is beneficial.

METHODS

This analysis was a planned extension of the previously published ARCTIC-Monitoring trial, in which we randomly allocated 2440 patients to a strategy of platelet function testing with antiplatelet treatment adjustment or a conventional strategy after coronary stenting with drug-eluting stent (DES). We recruited patients (aged 18 years or older) scheduled for planned DES implantation at 38 centres in France. After 1 year of follow-up, patients without contraindication to interruption of DAPT were eligible for a second randomisation to this second phase of the study (ARCTIC-Interruption). Using a computer-generated randomisation sequence (1:1; stratified by centre), we allocated patients to a strategy of interruption of DAPT where the thienopyridine was interrupted and single aspirin antiplatelet treatment was maintained (interruption group) or a strategy of DAPT continuation for 6-18 months (continuation group). The primary endpoint was the composite of death, myocardial infarction, stent thrombosis, stroke, or urgent revascularisation, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00827411.

FINDINGS

Between Jan 4, 2011, and March 3, 2012, 1259 eligible patients were randomly allocated to treatment in ARCTIC-Interruption: 624 to the interruption group and 635 to the continuation group. After a median follow-up of 17 months (IQR 15-18), the primary endpoint occurred in 27 (4%) patients in the interruption group and 24 (4%) patients in the continuation group (hazard ratio [HR] 1·17 [95% CI 0·68-2·03]; p=0·58). STEEPLE major bleeding events occurred more often in the continuation group (seven [1%] patients) compared with the interruption group (one [<0·5%] patient; HR 0·15 [0·02-1·20]; p=0·073). Major or minor bleedings were also more common in the continuation group compared with the interruption group (12 [2%] patients vs three [1%] patients; HR 0·26 [0·07-0·91]; p=0·04).

INTERPRETATION

Our finding suggests no apparent benefit but instead harm with extension of DAPT beyond 1 year after stenting with DES when no event has occurred within the first year after stenting. No conclusion can be drawn for high-risk patients who could not be randomised. The consistency between findings from all trials of such interruption suggests the need for a reappraisal of guidelines for DAPT after coronary stenting towards shorter duration of treatment.

FUNDING

Allies in Cardiovascular Trials Initiatives and Organized Networks (ACTION Study Group), Fondation de France, Sanofi-Aventis, Cordis, Medtronic, Boston Scientific, Fondation SGAM.

Long-term dual antiplatelet treatment and bleeding complications in diabetic patients treated with drug eluting stent implantation

BACKGROUND

Dual antiplatelet treatment (DAPLT) for at least 12 months is recommended after drug eluting stent (DES) implantation, but concerns regarding the extended use of this treatment persist due to increased risk of bleeding. In this study are assessed the incidence, correlates, and clinical significance of bleeding complications in diabetic patients after long-term DAPLT post DES implantation.

METHODS

We studied 610 consecutive diabetic patients after DES implantation. The primary end point was the occurrence of any bleeding according to the BARC and TIMI definitions.

RESULTS

The incidence of overall bleeding was higher in patients on DAPLT (21.1% vs. 4.4%, p < 0.001); minor/minimal according to the TIMI definition, and type 1 or 2 according to the BARC definition, were more frequently observed in patients on DAPLT (20.3% vs. 3.0%, p < 0.001, 15.6% vs. 2.0%, p < 0.001 and 4.4% vs. 0.5%, p = 0.034, respectively), whereas there was no effect on type 3 (3.5% vs. 2.0%, p = ns). DAPLT was an independent predictor for overall (HR 5.35, 95% CI: 2.69-10.67, p < 0.001), minor (HR 7.45, 95% CI: 3.25-17.12, p < 0.001, for TIMI classification) and type 1 or 2 bleeding (HR 8.17, 95% CI 3.29-20.25, p < 0.001); furthermore smoking was also predictor for overall bleeding (HR 1.65, 95% CI: 1.05-2.61, p = 0.030). Cardiovascular adverse events were not more frequent in patients with bleeding as compared with those without bleeding.

CONCLUSIONS

Long-term DAPLT in diabetic patients after DES implantation is associated with higher risk of overall and minor but not major bleeding; smoking may have a significant role in the occurrence of bleeding complications.

Efficacy and safety of a biodegradable polymer sirolimus-eluting stent in primary percutaneous coronary intervention: a randomized controlled trial

INTRODUCTION

With long-term follow-up, whether biodegradable polymer drug-eluting stents (DES) is efficient and safe in primary percutaneous coronary intervention (PCI) remains a controversial issue. This study aims to assess the long-term efficacy and safety of DES in PCI for ST-segment elevation myocardial infarction (STEMI).

MATERIAL AND METHODS

A prospective, randomized single-blind study with 3-year follow-up was performed to compare biodegradable polymer DES with durable polymer DES in 332 STEMI patients treated with primary PCI. The primary end point was major adverse cardiac events (MACE) at 3 years after the procedure, defined as the composite of cardiac death, recurrent infarction, and target vessel revascularization. The secondary end points included in-segment late luminal loss (LLL) and binary restenosis at 9 months and cumulative stent thrombosis (ST) event rates up to 3 years.

RESULTS

The rate of the primary end points and the secondary end points including major adverse cardiac events, in-segment late luminal loss, binary restenosis, and cumulative thrombotic event rates were comparable between biodegradable polymer DES and durable polymer DES in these 332 STEMI patients treated with primary PCI at 3 years.

CONCLUSIONS

Biodegradable polymer DES has similar efficacy and safety profiles at 3 years compared with durable polymer DES in STEMI patients treated with primary PCI.

Randomized comparison of Zotarolimus-Eluting Endeavor Sprint versus bare-metal stent implantation in uncertain drug-eluting stent candidates: rationale, design, and characterization of the patient population for the Zotarolimus-eluting Endeavor Sprint stent in uncertain DES candidates study

BACKGROUND

The use of drug-eluting stent (DES) instead of bare-metal stent (BMS) in patients at high stent thrombosis or bleeding risk as well as in those at low restenosis risk (ie, uncertain DES candidates) remains a matter of debate. Zotarolimus-Eluting Endeavor Sprint stent (E-ZES) (Santa Rosa, CA) is a hydrophilic polymer-based second-generation device with unique drug fast-release profile, which may allow for a shorter dual antiplatelet therapy (DAPT) duration without safety concerns.

HYPOTHESIS

The primary objective is to assess whether E-ZES implantation followed by a shorter than currently recommended course of DAPT will decrease the incidence of 12-month major adverse cardiovascular events as compared with BMS in undefined DES recipients. Actual duration of DAPT regimen will be dictated by patients' characteristics and not by stent type and, as such, can be as short as 30 days after intervention in both stent groups.

STUDY DESIGN

The ZEUS study is an open-label randomized clinical trial conducted at 20 clinical sites in Italy, Switzerland, Portugal, and Hungary. With 1,600 individuals, this study will have 85% power to detect a 33% difference in the primary end point consisting of the composite of death, nonfatal myocardial infarction, or target vessel revascularization.

SUMMARY

The ZEUS trial aims to assess whether the use of E-ZES, followed by a DAPT duration regimen based on patients' characteristics and not by stent type, is superior to conventional BMS implantation in undefined DES recipients who qualify for the presence of high thrombosis, bleeding, or low restenosis risk criteria.

Clopidogrel, prasugrel, or ticagrelor? a practical guide to use of antiplatelet agents in patients with acute coronary syndromes

Aspirin is a cornerstone of therapy in the treatment of patients with acute coronary syndromes (ACS). However, dual antiplatelet therapy reduces the risk of stent thrombosis and cardiovascular events compared with aspirin alone in the treatment of patients with ACS. Recently, there has been debate as to which antiplatelet agent should be added to aspirin in the ACS treatment regimen. This review summarizes the pharmacologic and clinical data comparing clopidogrel, prasugrel, and ticagrelor, and provides a practical guide to clinicians for determining which antiplatelet to use for patients with ACS.

First-in-man evaluation of the MOMO cobalt-chromium carbon-coated stent

AIMS

Bare metal stents continue to be used for the interventional treatment of coronary artery disease. We report the clinical and angiographic results of a multicentre, single-arm evaluation of safety and feasibility of the MOMO stent (Japan Stent Technology Co., Ltd, Okayama Research Park Incubation Centre, Okayama, Japan).

METHODS AND RESULTS

The MOMO stent is a novel thin-strut cobalt-chromium carbon-coated stent for the treatment of de novo coronary artery disease (CAD). In this prospective, non-randomised, single-arm study, 40 patients (stable and unstable angina) with single-vessel CAD were recruited into the study from three centres. Patients with lesions ≤15 mm in length and with a target vessel diameter of ≥3 mm were eligible. Angiographic follow-up was performed at six months. Quantitative coronary angiography (QCA) was used to measure acute gain and late luminal loss (LLL). Intravascular ultrasound (IVUS) was performed in 15 consecutive patients from two centres to assess the degree of neointimal proliferation within the stented segment at six-month follow-up. The MOMO stent performed well without any procedural complications with an acute procedure and technical success rate of 100%. Repeat revascularisation was performed in six patients (15%) during the six-month follow-up. Ischaemia-driven revascularisation was documented in three patients (7.5%). No myocardial infarction, stent thrombosis or cardiac death was observed. One non-cardiac death was reported secondary to lung cancer. Binary restenosis was 12.5% (n=5), and the LLL was 0.54±0.3 mm.

CONCLUSIONS

This first-in-man experience demonstrates proof of concept of the safety and feasibility of the MOMO cobalt-chromium carbon-coated stent for patients with single focal de novo lesions presenting with stable and unstable CAD.

Patients who require non-cardiac surgery in acute coronary syndrome

The coexistence of an acute coronary syndrome (ACS) and non-cardiac surgery (NCS) in an individual patient can be summarized in two challenging clinical scenarios for the treating physician: 1) Post-operative patients who develop ACS and 2) Patients with ACS who subsequently require NCS. Both settings are characterized by a struggle on the part of treating physicians attempting to optimize antithrombotic therapies for ACS while minimizing post-surgical bleeding risk. In this review we address specific clinical issues related to patients with coexistent NCS and ACS, discussing possible management strategies balancing ischemic and bleeding risk in these complex patient scenarios.

Recommendations for management of antiplatelet therapy in patients undergoing elective noncardiac surgery after coronary stent implantation

Patients commonly undergo noncardiac surgical procedures after implantation of a coronary stent. In the case where surgery cannot be deferred until completing the minimum duration of dual antiplatelet therapy, the Brigham and Women's Hospital Cardiac Catheterization Laboratory recommends using a glycoprotein IIb/IIIa bridging protocol to minimize the risk of perioperative ischemic events. We discuss our algorithm for managing antiplatelet agents, including the newer agents, prasugrel and ticagrelor, in patients undergoing noncardiac surgery after coronary stenting and present our glycoprotein IIb/IIIa bridging strategy along with a review of the relevant pharmacodynamic and clinical evidence.