Experimental results of crystal-assisted slow extraction at the SPS

The possibility of extracting highly energetic particles from the Super Proton Synchrotron (SPS) by means of silicon bent crystals has been explored since the 1990's. The channelling effect of a bent crystal can be used to strongly deflect primary protons and eject them from the synchrotron. Many studies and experiments have been carried out to investigate crystal channelling effects. The extraction of 120 and 270 GeV proton beams has already been demonstrated in the SPS with dedicated experiments located in the ring. Presently in the SPS, the UA9 experiment is performing studies to evaluate the possibility to use bent silicon crystals to steer particle beams in high energy accelerators. Recent studies on the feasibility of extraction from the SPS have been made using the UA9 infrastructure with a longer-term view of using crystals to help mitigate slow extraction induced activation of the SPS. In this paper, the possibility to eject particles into the extraction channel in LSS2 using the bent crystals already installed in the SPS is presented. Details of the concept, simulations and measurements carried out with beam are presented, before the outlook for the future is discussed.Comment: 4 pages, 7 figures, submitted to to International Particle Accelerator Conference (IPAC) 2017 in Copenhagen, Denmar

Value of the SYNTAX score for periprocedural myocardial infarction according to WHO and the third universal definition of myocardial infarction:insights from the TWENTE trial

Aims: The SYNTAX score is a tool to quantify the complexity of coronary artery disease. We investigated the relation between the SYNTAX score and the occurrence of a periprocedural myocardial infarction (PMI) according to the historical definition of the World Health Organization (WHO) and the recently updated universal definition of MI. Methods and results: The SYNTAX score was calculated in 1,243 patients enrolled in TWENTE, a randomised trial which assessed second-generation drug-eluting stents. PMI was defined by the WHO definition and the third universal definition of MI. Patients were divided into tertiles of the SYNTAX score: ≤7 (n=430); >7 and <15 (n=390); ≥15 (n=423). PMI according to the WHO definition occurred more frequently in patients in the highest SYNTAX score tertile (7.3% vs. 3.1% vs. 1.6%, p<0.001) compared to the mid and lowest tertile. Similar findings were seen for universal PMI (9.9% vs. 7.7% vs. 3.7%, p<0.01). After multivariate analysis, SYNTAX score was a significant independent correlate of PMI for both definitions: the highest SYNTAX score tertile had an almost five times higher risk for WHO PMI, and a three times higher risk for universal PMI. Conclusions: In a broad patient population treated with second-generation DES, the SYNTAX score was able to stratify the risk of PM

Safety of second-generation drug-eluting stents three years after randomised use in the TWENTE trial

Aims: To assess three-year clinical outcome following randomised use of the second-generation Resolute zotarolimus-eluting stent (ZES) and the XIENCE V everolimus-eluting stent (EES). For Resolute ZES and randomised use, outcome data ≥3 years are relatively scarce. Methods and results: The TWENTE trial examined 1,391 patients with stable angina or non-ST-elevation acute coronary syndromes, of whom 21.6% were diabetics, 70.1% had complex B2 or C lesions and 77.4% had “off-label” indications for DES use. Three-year follow-up data were obtained in 1,381 patients (99.3%; 10 withdrawals). Adverse clinical events were independently adjudicated. The primary endpoint target vessel failure (TVF), a composite of cardiac death, target vessel-related myocardial infarction and clinically indicated target vessel revascularisation, was 12.1% for Resolute ZES and 13.4% for XIENCE V EES (p=0.50). Cardiac death rates were 1.9% vs. 3.5% (p=0.06); the other individual components of TVF also showed no significant between-group differences. The rates of definite-or-probable stent thrombosis (1.4% vs. 1.6%, p=0.82) and very late stent thrombosis (0.6% vs. 0.4%, p=1.0) did not differ between the groups. Conclusions: Three-year follow-up data of patients included in the randomised TWENTE trial demonstrated similar and sustained safety and efficacy of Resolute ZES and XIENCE V EE

Four-year clinical outcome following randomised use of zotarolimus-eluting stents versus everolimus-eluting stents in all-comers: Insights from the DUTCH PEERS trial

Background: The DUTCH PEERS (TWENTE II) trial (clinicaltrials.gov NCT01331707) is a randomised, multicenter, single-blinded, investigator initiated all-comers trial. All coronary syndromes were permitted with no limit for lesion length, reference size, or number of lesions or diseased vessels to be treated. In total, 1811 patients were 1:1 randomised to cobalt chromium-based zotarolimuseluting stents (ZES) versus platinum chromium-based everolimus-eluting stents (EES). These durable polymer-based drug-eluting stents (DES) were developed to facilitate device deliverability and to improve stent apposition to the vessel wall. Purpose: We assessed the 4-year clinical outcome of the DUTCH PEERS trial in terms of safety and efficacy. Methods: Clinical outcome was assessed by means of follow-up data of the trial participants. The primary endpoint target vessel failure (TVF) is a composite of cardiac death, target vessel-related myocardial infarction (MI) or target vessel revascularization. Secondary endpoints included the individual components of the TVF and the incidence of definite-or-probable stent thrombosis. Endpoints were analyzed by the logrank test by comparing the time to the endpoint, using the Kaplan-Meier method. Independent contract research organizations performed the study monitoring and clinical event adjudication. Results: The 4-year clinical follow-up data were available in 1802 patients (99.5%; 4 patients were lost to follow-up and 5 withdrew consent). The ZES and EES groups showed favourable outcomes with a similar incidence of TVF (12.1% vs. 12.1%; Logrank p=0.95). The rates of the individual components of TVF were also similar for both stent arms: cardiac death (3.9% vs. 3.7%; Logrank p=0.78); target vessel-related MI (3.2% vs. 2.5%; Logrank p=0.38); and target vessel revascularization (6.8% vs. 7.5%; Logrank p=0.55), respectively. In addition, the incidence of definite-or-probable stent thrombosis was similar for patients treated with ZES versus EES (1.5% vs. 1.2%; Logrank p=0.67). Conclusion: At 4-year follow-up, ZES and EES showed similar and sustained results in terms of safety and efficacy for treating all-comer patients

Impact of previous coronary artery bypass surgery on clinical outcome after percutaneous interventions with second generation drug-eluting stents in TWENTE trial and Non-Enrolled TWENTE registry

AbstractBackgroundPatients with previous coronary artery bypass grafting (CABG) who underwent percutaneous coronary intervention (PCI) have an increased repeat revascularization rate, but data on contemporary second-generation drug-eluting stents (DES) are scarce.MethodsWe evaluated 1-year clinical outcome following secondary revascularization by PCI in patients of the TWENTE trial and non-enrolled TWENTE registry, and compared patients with previous CABG versus patients without previous CABG.ResultsOf all 1709 consecutive patients, 202 (11.8%) had previously undergone CABG (on average 11.2±8.5years ago). CABG patients were older (68.5±9.4years vs. 64.1±10.7years, P<0.001) and more often had diabetes (28.7% vs. 20.9%, P=0.01) and previous PCI (40.1% vs. 19.8%, P<0.001) compared to patients without previous CABG. Nevertheless, a higher target vessel revascularization (TVR) rate following PCI in the CABG patients (9.4% vs. 2.3%, P<0.001) was the only significant difference in clinical outcome at 1-year follow-up (available for 99.6%). Among CABG patients, the TVR rate was significantly higher in patients treated for graft lesions (n=65; 95.4% in vein grafts) than in patients treated for native coronary lesions only (n=137) (18.5% vs. 5.1%, P=0.002). Among 1638 patients with PCI of native coronary lesions only, there was only a non-significant difference in TVR between patients with previous CABG versus patients without previous CABG (5.1% vs. 2.3%, P=0.08).ConclusionsPatients with previous CABG showed a favorable safety profile after PCI with second-generation DES. Nevertheless, their TVR rate was still much higher, driven by more repeat revascularizations after PCI of degenerated vein grafts. In native coronary lesions, there was no such difference

Patient preference regarding assessment of clinical follow-up after percutaneous coronary intervention: the PAPAYA study

Aims: To keep patients in long-term clinical follow-up programmes after percutaneous coronary intervention (PCI), knowledge of the patient-preferred mode for follow-up assessment is crucial. We systematically assessed patient preference, and explored potential relationships with age and gender.Methods and results: In the prospective, observational PAPAYA study (ClinicalTrials.gov: NCT02189070), 2,566 patients, treated by PCI between June 2008 and May 2012, were invited to participate in a postal survey on the patient-preferred mode (postal questionnaire, telephone or e-mail consultation) and frequency of follow-up assessment. A total of 1,797 (70.0%) patients responded. The vast majority preferred completing postal questionnaires (1,248 [69.9%]) as compared to telephone (240 [13.4%]) or e-mail-based approaches (227 [12.7%]) (p<0.001). With increasing age, there was a gradual decline in preference for e-mail (p<0.001); the youngest patients (≤60 years) preferred e-mail-based follow-up more often than the oldest (21.1% vs. 3.1%). Nevertheless, 79.9% of the youngest preferred to be approached in ways other than by e-mail. Women more often preferred approaches other than e-mail (94.1% vs. 87.3%, p<0.001).Conclusions: Patients showed a distinct preference for completing postal questionnaires rather than being approached by telephone or e-mail. Younger patients accepted e-mail-based follow-up more often, but the majority of the youngest patients still preferred approaches other than by e-mail - See more at: http://www.pcronline.com/eurointervention/ahead-of-print/201510-06/patient-preference-regarding-assessment-of-clinical-follow-up-after-percutaneous-coronary-intervention-the-papaya-study

Comparison of eligible non-enrolled patients and the randomised TWENTE trial population treated with Resolute and XIENCE V drug-eluting stents

Aims: The TWENTE trial recently enrolled more than 80% of all eligible patients, who were randomised to zotarolimus-eluting Resolute or everolimus-eluting XIENCE V stents. In the present study, we investigated whether eligible, non-enrolled patients differed from the randomised TWENTE trial population in baseline characteristics and one-year outcome. Methods and results: Characteristics of 1,709 eligible patients were analysed. Independent external adjudication of clinical events was likewise performed for non-enrolled (n=318) and randomised patients (n=1,391). Non-enrolled and randomised patients did not differ in gender distribution, diabetes mellitus, and clinical presentation, but differed significantly in age and cardiovascular history. Nevertheless, clinical outcome after one year did not differ in the primary composite endpoint target-vessel failure (TVF; 9.8% vs. 8.1%; p=0.34), and its components cardiac death (1.6% vs. 1.2%; p=0.61), target vessel-related myocardial infarction (4.7% vs. 4.6%; p=0.92), and target-vessel revascularisation (3.8% vs. 3.0%; p=0.48). Previous bypass surgery predicted TVF in non-enrolled patients (p=0.001); removal of these patients resulted in identical TVF rates for non-enrolled and randomised patients (7.3% vs. 7.3%; p=0.99). Conclusions: Despite some differences in baseline characteristics, non-enrolled and randomised patients did not differ in one-year outcome, which was favourable for both populations and may be related to the drug-eluting stents used

TCT-588 2-Year Clinical Outcome of the Randomized, Multicenter DUTCH PEERS (TWENTE II) Trial, Comparing Cobalt-Chromium Zotarolimus-Eluting Resolute Integrity Stents and Platinum-Chromium Everolimus-Eluting Promus Element Stents in “All-Comer” Patients

Background: The multicenter, prospective, randomized, single-blinded, investigator-initiated DUTCH PEERS (TWENTE II) “All Comers” Trial demonstrated at 1-year follow-up the non-inferiority of third-generation Resolute Integrity zotarolimus-eluting stents (Medtronic Vascular, Santa Rosa, CA) versus Promus Element everolimus-eluting stents (Boston Scientific, Natick, MA), based on a similar incidence of the primary endpoint target vessel failure (TVF), a composite of cardiac death, target vessel revascularization (TVR), or myocardial infarction (MI). No other follow-up data beyond 12 months have been published from a randomized head-to-head comparison of both stents. Methods: In 4 study centers in the Netherlands, 1,811 patients were 1:1 randomly assigned to treatment with one of both stents. Patients with any clinical syndrome, any lesion type, and any number of lesions or vessels to be treated were included. Study monitoring and clinical event adjudication were performed by two independent Dutch contract research organizations (Diagram, Zwolle, and Cardialysis, Rotterdam, respectively). Results: DUTCH PEERS examines an all-comer patient population that included 59% of patients with acute coronary syndromes (20% of all patients presented with an acute STEMI) and 66% of patients with complex target lesions. We will compare for both stent groups the 2-year incidence of TVF (primary endpoint) and various secondary endpoints, including individual components of the primary endpoint, the incidence of stent thrombosis, and other composite endpoints, such as target lesion failure, major adverse cardiac events, and the patient-oriented composite endpoint. In addition, we will report the outcome of patients with longitudinal stent deformation after discontinuation of dual anti-platelet therapy. Conclusions: Clinical outcome of the DUTCH PEERS trial at 2-year follow-up will be presented