Search

Resumen Introduccion y objetivos El objetivo es evaluar el impacto del acceso vascular en las complicaciones hemorragicas tras una intervencion coronaria percutanea en pacientes con alto riesgo de sangrado (ARS) a los 30 dias y a los 2 anos. Metodos El presente estudio es un subanalisis predefinido del estudio LEADERS FREE, que incluyo a 2.432 pacientes con ARS y en el que el stent farmacoactivo Biolimus A9 resulto superior al stent convencional en seguridad y eficacia. Resultados El acceso radial (AR) se utilizo en 1.454 pacientes (59,8%) y el femoral (AF), en 978 (40,2%), ambos a eleccion del operador. La seguridad y los beneficios del stent farmacoactivo sobre el convencional fueron independientes del acceso vascular. A los 30 dias y a los 2 anos, habian sufrido un sangrado mayor el 2,4 y el 7,5% de los pacientes con AR y el 4,6 y el 10,9% de los pacientes con AF (p = 0,003), la mayoria en ambos grupos (el 2,1 y el 7,0% del de AR; el 3,2 y el 9,4% del de AF) no relacionados con el sitio de acceso vascular. El AR se asocio con una reduccion significativa en las tasas ajustadas de sangrado mayor tanto a 30 dias (HR = 1,98; IC95%, 1,25-3,11; p = 0,003) como a 2 anos de seguimiento (HR = 1,51; IC95%, 1,14-2,01; p = 0,003). Conclusiones Los operadores prefirieron el AR en la mayoria de los pacientes con ARS, lo cual se asocio con una reduccion significativa del sangrado mayor. Asimismo, un numero significativo de sangrados en el seguimiento de esta poblacion son no relacionados con el acceso vascular.

The aim of our study is to assess the impact of anemia, chronic kidney disease, and diabetes mellitus on platelet reactivity (PR) in patients with severe aortic stenosis, both at baseline and after transcatheter aortic valve implantation (TAVI). This study is a prespecified subanalysis of the REAC-TAVI prospective, multicenter trial that included patients pretreated with aspirin + clopidogrel before TAVI. PR was measured at baseline and at 5 different time points after TAVI with the VerifyNow assay (Accriva Diagnostics, San Diego, CA), over a 3-month follow-up period. Patients with high PR (HPR) at baseline, before TAVI (n = 48) were randomized to aspirin + clopidogrel or aspirin + ticagrelor for 3 months, whereas those with normal PR (NPR) (n = 20) were continued on aspirin + clopidogrel. A "raiser response" in PR was defined as an increase in PR units >20% of baseline after TAVI. Patients with HPR before TAVI presented concomitant anemia and chronic kidney disease more frequently than their counterparts with NPR. Anemia and higher body mass index were independently associated with HPR to clopidogrel at baseline. Moreover, anemic patients with baseline HPR who were continued on clopidogrel presented higher PR after TAVI than patients with HPR switched to ticagrelor. All patients with baseline NPR presented a "raiser response" after TAVI, which was nonexistent among patients with HPR managed with ticagrelor. In summary, anemia seems as a relevant factor associated with baseline HPR and higher PR after TAVI in patients with baseline HPR randomized to clopidogrel, whereas ticagrelor proved more effective than clopidogrel at attaining sustained reductions in PR during follow-up, regardless of baseline comorbidities.

Ticagrelor has proven more effective than clopidogrel at attaining a maintained suppression of high platelet reactivity (HPR) in aortic stenosis patients undergoing transcatheter aortic valve implantation (TAVI). This study aims to assess the influence of implanted valve type on the degree of platelet reactivity (PR) after TAVI.This study is a prespecified analysis of REAC-TAVI, a prospective, multicenter study that included patients on dual-antiplatelet therapy with aspirin and clopidogrel before TAVI. Patients with HPR (n = 48) were randomized to aspirin and clopidogrel or aspirin and ticagrelor for 3 months, while those without HPR (n = 20) were continued on aspirin and clopidogrel. PR was measured 6 hours, 24 hours, 5 days, 30 days, and 90 days after TAVI with VerifyNow assay. Bioprosthetic valves were classified as balloon-expandable valve (BEV), self-expandable valve (SEV), or other.Sixty-eight patients comprising 32 BEVs, 28 SEVs, and 8 other valves were included. Devices were larger and postdilation was more frequent in the SEV group. Follow-up PR was lower in patients treated with ticagrelor vs those treated with clopidogrel at all time points after TAVI, including patients without baseline HPR (P.001). PR after TAVI was similar in the three groups. Major cardiovascular adverse events, stroke, and hemorrhagic complications were comparable across the different bioprosthesis groups at 4-month follow-up.The effect of valve type on PR after TAVI is similar across the spectrum of most transcatheter valves. In our sample, ticagrelor achieved a faster and more effective reduction in PR than clopidogrel in patients with HPR undergoing TAVI, irrespective of valve type.

OBJECTIVES: The REAC-TAVI (Assessment of platelet REACtivity after Transcatheter Aortic Valve Implantation) trial enrolled patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) pre-treated with aspirin + clopidogrel, aimed to compare the efficacy of clopidogrel and ticagrelor in suppressing high platelet reactivity (HPR) after TAVI. BACKGROUND: Current recommendations support short-term use of aspirin + clopidogrel for patients with severe AS undergoing TAVR despite the lack of compelling evidence. METHODS: This was a prospective, randomized, multicenter investigation. Platelet reactivity was measured at 6 different time points with the VerifyNow assay (Accriva Diagnostics, San Diego, California). HPR was defined as (P2Y12 reaction units (PRU) ≥208. Patients with HPR before TAVR were randomized to either aspirin + ticagrelor or aspirin + clopidogrel for 3 months. Patients without HPR continued with aspirin + clopidogrel (registry cohort). The primary endpoint was non-HPR status (PRU

Introduction and objectives The prognostic impact of bleeding in high bleeding risk (HBR) patients depending on the location of bleeding and prognosis in nonaccess site bleeding is unknown. We aimed to assess the impact of vascular access site on bleeding complications after percutaneous coronary interventions for HBR patients at 30-day and 2-year follow-up. Methods The LEADERS FREE trial included 2432 HBR PCI patients. A Biolimus A9 drug-coated stent was superior to a bare-metal stent for safety and efficacy. This is a predefined sub-analysis of the LEADERS FREE trial. Results Transradial access (TRA) was used in 1454 patients (59.8%) and transfemoral access (TFA) in 978 (40.2%), according to operator preference. The safety and benefits of drug-coated stents over bare-metal stents were independent of vascular access. At 30 days and 2 years, major bleeding had occurred in 2.4% and 7.5% of TRA patients and 4.6% and 10.9% of TFA patients (P = .003), respectively. Most of these events in both groups (2.1% and 7.0% for TRA; 3.2% and 9.4% for TFA, respectively) were nonaccess site-related. TRA was associated with a significant reduction in adjusted rates of major bleeding both at 30 days (HR, 1.98; 95%CI, 1.25-3.11; P = .003) and at 2 years of follow-up (HR, 1.51; 95%CI, 1.14-2.01; P = .003). This difference was driven by both access and nonaccess bleeding. Conclusions Operators preferred TRA for most HBR patients, which was associated with a significant reduction in major bleeding events. However, most of these events in this population are unrelated to vascular access.

The ALMA telescope will be composed of 66 high precision ante nnas; each antenna producing 8 times 2GHz bandwidth signals (4 pairs or orthogonal linear polarizations signals). Detecting the root cause of a loss of coherence issue between pairs of antennas can take valuable time which could be used for scientific purposes. This work presents an approach for quickly determining, in a systematic fashion, the source of th is kind of issues. Faulty sub- system can be detected using the telescope calibration software and the granularity information. In a complex instrument such as the ALMA telescope, finding the cause of a loss of coherence issue can be a cumbersome task due to the several sub-systems involved on the signal processing (Frequency down-converter, analog and digital filters, instrumental delay), the interdependenc ies between sub-systems can make this task even harder. A method based on the information provided by the TelCal 1 sub-system (in specific the Delay Measurements) will be used to help identify either the faulty unit or the wrong conf iguration which is causing the loss of coherence issue. This method uses granularity information to help find the cause of the problem. Keywords: radio-telescope, coherence

The ALMA telescope is composed of 66 high precision antennas, each antenna having 8 high bandwidth digitizers (4Gsamples/Second). It is a critical task to determine the well functioning of those digitizers prior to starting a round of observations. Since observation time is a valuable resource, it is germane that a tool be developed which can provide a quick and reliable answer regarding the digitizer status. Currently the digitizer output statistics are measured by using comparators and counters. This method introduced uncertainties due to the low amount of integration, in addition to going through all the possible states for all available digitizer time which all resulted in the antennas taking a considerable amount of time. In order to avoid the aforementioned described problems, a new method based on correlator resources is hereby presented.

Nowadays, more centers worlwide preferred the radial access as first choice to perform left cardiac catheterization. However, the radial approach might challenge operators with several anatomical problems and complications such as accessory radial artery, tortuosity, loop, spasm, dissection

Background: Very late stent thrombosis (VLST) after bare-metal stent (BMS) implantation is a rare complication. There is emerging evidence suggesting that in-stent neoatherosclerosis may play a role, but data on clinical characteristics and prognosis of patients (p) are limited. The aim of this study was to evaluate the profile and outcome of VLST after BMS implantation treated with percutaneous coronary intervention (PCI). Methods: From January 2006 to May 2012 a total of 9,582 PCI were performed at our center. During this period we identified and retrospectively analyzed 30 consecutive p with angiographically confirmed VLST related to BMS. Minimum follow-up period of 1 year and 2 years was available in 25/30 and 23/30 p, respectively. Results: Mean age of p was 60 13 years, 93% were male, 53% active smokers, 20% diabetics, 77% had hyperlipidemia and 67% hypertension. Clinical presentation of VLST after BMS was ST-segment elevation myocardial infarction (STEMI) in 27 cases, and 3 p (10%) had non-STEMI. Right coronary artery was the most common location of VLST (57%). Median period from BMS implantation to VLST was 7.9 years (interquartile range, 6.0-9.9 years) and most of the p (70%) were receiving oral antiplatelet therapy at the time of VLST (67% aspirin alone, 3% dual antiplatelet). All p with VLST after BMS underwent successful PCI. Effective thrombus aspiration was achieved in 67% of p and a new stent was deployed in 83% of p (14 DES, 11 BMS). A significant deterioration of LVEF occurred in p with VLST related to BMS (64 6% to 50 9%; p 0.001). Major adverse cardiac events (cardiovascular death or myocardial infarction) rates were 7%, 20%, and 39% at 30 days, 1-year and 2-year follow-up, respectively. During the 2-year follow-up period 3 p died and 6 p had a non-fatal myocardial infarction (recurrent stent thrombosis in 3 p and myocardial infarction not related to prior VLST in 3 p). Conclusions: VLST after BMS implantation is an uncommon phenomenon, mainly presented as STEMI, and its treatment with a new PCI is feasible and effective. Nevertheless new major adverse cardiac events may occur in this group of p at shortand mid-term follow-up, related to both prior VLST and coronary disease progression.

Transradial approach has gained progressive acceptance because it has been shown to have fewer hemorrhagic and vascular-related complications than the femoral approach does for diagnostic and therapeutic percutaneous coronary artery procedures. However, transradial access is not free of