Effect of COMBinAtion therapy with remote ischemic conditioning and exenatide on the Myocardial Infarct size: a two-by-two factorial randomized trial (COMBAT-MI)

Remote ischemic conditioning (RIC) and the GLP-1 analog exenatide activate different cardioprotective pathways and may have additive effects on infarct size (IS). Here, we aimed to assess the efficacy of RIC as compared with sham procedure, and of exenatide, as compared with placebo, and the interaction between both, to reduce IS in humans. We designed a two-by-two factorial, randomized controlled, blinded, multicenter, clinical trial. Patients with ST-segment elevation myocardial infarction receiving primary percutaneous coronary intervention (PPCI) within 6 h of symptoms were randomized to RIC or sham procedure and exenatide or matching placebo. The primary outcome was IS measured by late gadolinium enhancement in cardiac magnetic resonance performed 3–7 days after PPCI. The secondary outcomes were myocardial salvage index, transmurality index, left ventricular ejection fraction and relative microvascular obstruction volume. A total of 378 patients were randomly allocated, and after applying exclusion criteria, 222 patients were available for analysis. There were no significant interactions between the two randomization factors on the primary or secondary outcomes. IS was similar between groups for the RIC (24 ± 11.8% in the RIC group vs 23.7 ± 10.9% in the sham group, P = 0.827) and the exenatide hypotheses (25.1 ± 11.5% in the exenatide group vs 22.5 ± 10.9% in the placebo group, P = 0.092). There were no effects with either RIC or exenatide on the secondary outcomes. Unexpected adverse events or side effects of RIC and exenatide were not observed. In conclusion, neither RIC nor exenatide, or its combination, were able to reduce IS in STEMI patients when administered as an adjunct to PPCI

Differential clinical characteristics and prognosis of intraventricular conduction defects in patients with chronic heart failure

Intraventricular conduction defects (IVCDs) can impair prognosis of heart failure (HF), but their specific impact is not well established. This study aimed to analyse the clinical profile and outcomes of HF patients with LBBB, right bundle branch block (RBBB), left anterior fascicular block (LAFB), and no IVCDs. Clinical variables and outcomes after a median follow-up of 21 months were analysed in 1762 patients with chronic HF and LBBB (n = 532), RBBB (n = 134), LAFB (n = 154), and no IVCDs (n = 942). LBBB was associated with more marked LV dilation, depressed LVEF, and mitral valve regurgitation. Patients with RBBB presented overt signs of congestive HF and depressed right ventricular motion. The LAFB group presented intermediate clinical characteristics, and patients with no IVCDs were more often women with less enlarged left ventricles and less depressed LVEF. Death occurred in 332 patients (interannual mortality = 10.8%): cardiovascular in 257, extravascular in 61, and of unknown origin in 14 patients. Cardiac death occurred in 230 (pump failure in 171 and sudden death in 59). An adjusted Cox model showed higher risk of cardiac death and pump failure death in the LBBB and RBBB than in the LAFB and the no IVCD groups. LBBB and RBBB are associated with different clinical profiles and both are independent predictors of increased risk of cardiac death in patients with HF. A more favourable prognosis was observed in patients with LAFB and in those free of IVCDs. Further research in HF patients with RBBB is warranted

Verification of a laser tracker with an indexed metrology platform

This work presents the development of a new verification procedure for laser trackers with an indexed metrology platform. The applicable standards which guide the calibration and verification procedures for laser trackers are ASME B89.4.19-2006, VDI/VDE 2617-2011 part 10 and the draft of ISO/CD10360-10 standard. All of them define a range of comparable tests for evaluating the performance of a laser tracker using calibrated artifacts for reference lengths definition. In this case, the use of an indexed metrology platform enables the evaluation of different working volumes of the laser tracker using the same physical calibrated gauge which remains still during the verification procedure//meanwhile, the laser tracker rotates with the platform. This is possible due to the six rotating positions of the platform and its ability to express points in a global reference system located in the lower platform. To overcome this, the kinematic modeling of the laser tracker is made together with its integration with the mathematical model of the platform. Then, the theoretical verification procedure of the laser tracker with the indexed metrology platform is developed, followed by an experimental phase where the verification procedure is carried out with a big dimension mesh of retroreflectors and a physical gauge which is used as a reference. The results obtained in the verification procedure validate the use of the indexed metrology platform in verification procedures for laser trackers, showing its advantages in terms of coverage of the instrument working volume, testing time reduction, and test setup simplification

Dossier "Palabra e imagen"

El siglo XX fue el siglo de la imagen. Y ella ha sido –y sigue siendo- un motor de producción iconográfica global. Alguno de los hechos más significativos del pasado siglo fueron afectados (cuando no, directamente producidos) por la dimensión visual de un acontecimiento histórico. Baste pensar en el ejemplo que sigue: la liberación de la Europa del nazismo fue a manos del ejército rojo –sea por los planes estratégicos de contención, sea por las bajas del propio despliegue ruso, sea por la transmisión oral de los pueblos liberados- ello unido, si bien en menor medida, al concurso de los ejércitos aliados en la contienda: éstos últimos con un papel coadyuvante, casi subordinado al rol soviético en los frentes orientales. Ese rol secundario aliado era percibido por todos los estamentos de la sociedad europea. Y, tras más de medio siglo de producción iconográfica norteamericana (muy especialmente en el campo de la cinematografía de Hollywood), la responsabilidad de la derrota del nacismo no recae, a ojos de la opinión pública -como en los años coetáneos al propio acontecimiento- en el ejército ruso: las generaciones más jóvenes, como recientemente analizó un estudio[1], creen firmemente que el ejército americano derrotó él sólo al nacismo, quizás con alguna ayuda europea. La imagen ha cambiado la historia, y no sólo: también la manera de contarla y cantarla. En el siglo XXI este poder se ha multiplicado exponencialmente, tejiendo una nueva relación entre la fotografía y la ciudadanía. Tamizando cada acto vital (un café, un paseo, una comida o una ducha) con su consecuente realización fotográfica del momento y su plasmación en los social media

Differential clinical characteristics and prognosis of intraventricular conduction defects in patients with chronic heart failure

Intraventricular conduction defects (IVCDs) can impair prognosis of heart failure (HF), but their specific impact is not well established. This study aimed to analyse the clinical profile and outcomes of HF patients with LBBB, right bundle branch block (RBBB), left anterior fascicular block (LAFB), and no IVCDs. Clinical variables and outcomes after a median follow-up of 21 months were analysed in 1762 patients with chronic HF and LBBB (n = 532), RBBB (n = 134), LAFB (n = 154), and no IVCDs (n = 942). LBBB was associated with more marked LV dilation, depressed LVEF, and mitral valve regurgitation. Patients with RBBB presented overt signs of congestive HF and depressed right ventricular motion. The LAFB group presented intermediate clinical characteristics, and patients with no IVCDs were more often women with less enlarged left ventricles and less depressed LVEF. Death occurred in 332 patients (interannual mortality = 10.8%): cardiovascular in 257, extravascular in 61, and of unknown origin in 14 patients. Cardiac death occurred in 230 (pump failure in 171 and sudden death in 59). An adjusted Cox model showed higher risk of cardiac death and pump failure death in the LBBB and RBBB than in the LAFB and the no IVCD groups. LBBB and RBBB are associated with different clinical profiles and both are independent predictors of increased risk of cardiac death in patients with HF. A more favourable prognosis was observed in patients with LAFB and in those free of IVCDs. Further research in HF patients with RBBB is warranted