José M. Rodríguez

Coronariografía y angioplastia coronaria por vía radial: experiencia inicial y curva de aprendizaje

Introduction. The transradial approach has emerged as an attractive alternative to the femoral approach for coronary angiography and interventions. We describe our experience with the transradial approach and analyze the influence of the learning curve. Patients and methods. The transradial approach was attempted in patients with a good radial pulse and normal Allen test. When feasible and clinically indicated, we attempted ad hoc intervention. We divided the study population into two groups: Group A (the first 200 cases) and B (all other patients). We compared the radial group with a matched femoral control group. Results. We attempted the transradial approach in 526 patients (77.6% male; age 63.5 ± 11.51), and obtained a success rate of 93.7%. We found differences between group A and B in the success rate (91.0 vs 95.4%, p = 0,04), duration of procedure [23 (16-29) vs. 19 (15-24) minutes; p < 0.001], and fluoroscopy time [6.4 (4.2-10) vs. 5.0 (3.0-7.7) minutes; p < 0,001]. At 24 h of follow-up, we found small hematomas in 9.4%, bleeding in 4.9%, and radial artery obstruction in 2.8%, with no cases of arteriovenous fistula, pseudoaneurysm, or need for vascular surgery. We attempted intervention in 169 patients with 258 lesions, achieving angiographic success in 96.1%. We found no differences in the characteristics of the lesions and patients, or in the angiographic success rate of the radial and femoral PTCA groups. Conclusions. The transradial approach is a safe and effective alternative to femoral catherization. There is a significant learning curve associated with the successful performance of transradial procedures.Introduccion La via transradial ha surgido como una alternativa atractiva a la via femoral para realizar coronariografias e intervenciones coronarias. Describimos nuestra experiencia y analizamos la influencia de la curva de aprendizaje. Pacientes y metodos El abordaje transradial se intento en pacientes con pulso radial y test de Allen normales. Cuando se considero posible e indicado, se realizo una intervencion coronaria en el mismo procedimiento. Dividimos a la poblacion de estudio en 2 grupos: A (primeros 200 casos) y B (el resto de los pacientes). Comparamos el grupo radial con un grupo control femoral. Resultados Intentamos el acceso radial en 526 pacientes (77,6% varones; edad, 63,5 ± 11,51 anos), con exito en el 93,7%. Encontramos diferencias entre los grupos A y B en la proporcion de procedimientos con exito (91,0 frente a 95,4%; p = 0,04), los tiempos de procedimiento (23 [16–29] frente a 19 [15–24] min; p Conclusiones La via radial es una alternativa segura y eficaz a la femoral. Existe una curva de aprendizaje significativa asociada a los procedimientos por via radial.

Asymptotic derivation of a general linear model for thin-walled elastic rods☆

In this work we derive from three-dimensional elasticity a general mathematically justified theory for thin-walled elastic rods. This theory is obtained as an asymptotic approximation of the three-dimensional linear model as the area and the thickness of the cross-section becomes successively small. It constitutes an extension of the classical Vlassovs theory for thin-walled beams (the most complete among models currently used in engineering).

Comparacion del valor predictivo pronostico de los scores TIMI, PAMI, CADILLAC y GRACE en el SCACEST sometido a ICP primario o de rescate

INTRODUCTION AND OBJECTIVES We sought to compare the predictive value of the Thrombolysis In Myocardial Infarction (TIMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC), Primary Angioplasty in Myocardial Infarction (PAMI), and Global Registry for Acute Coronary Events (GRACE) scores for the outcome of ST-segment elevation acute coronary syndrome undergoing urgent percutaneous coronary intervention. METHODS We performed a retrospective analysis of a cohort composed of all consecutive patients with ST-segment elevation acute coronary syndrome treated by urgent percutaneous coronary intervention between 2006 and 2010 (n=1503). TIMI, PAMI, CADILLAC, and GRACE risk scores were calculated for each patient according to different clinical variables. We assessed the predictive accuracy of these scores for death, reinfarction, and target-vessel revascularization at 30 days and 1 year, using the C statistic, which was obtained by means of logistic regression and ROC curves. RESULTS The TIMI, PAMI, CADILLAC and GRACE showed an excellent predictive value for 30-day and 1-year mortality (C statistic range, 0.8-0.9), with superiority of the TIMI, CADILLAC, and GRACE risk models. The performance of these 4 scores was poor for both reinfarction and target-vessel revascularization (C statistic, 0.5-0.6). CONCLUSIONS The TIMI, PAMI, CADILLAC, and GRACE scores provide excellent information to stratify the risk of mortality in patients treated by percutaneous coronary intervention. The TIMI, CADILLAC, and GRACE models have higher predictive accuracy. The usefulness of these models for reinfarction and target-vessel revascularization prediction is questionable.

Ecocardiografía de ejercicio para diferenciar la miocardiopatía dilatada de la disfunción ventricular por cardiopatía isquémica

Objectives. Previous studies have shown the usefulness of dobutamine echocardiography to differentiate dilated cardiomyopathy (DC) from ischemic left ventricular dysfunction (ILVD), but no studies have been made using exercise echocardiography (EE). We hypothesized that most patients with DC have some contractile reserve and experience an increase in left ventricular ejection fraction (LVEF) during exercise, as opposed to patients with ILVD. Differences in response to EE may be useful to clinically differentiate between these two entities. Patients and method. Between 1 March 1995 and 1 March 2001, we performed 4,133 EE studies on 3,830 patients. Of 289 patients (8%) with moderate or severe LV dysfunction (biplane LVEF 5.2 cm), 207 were excluded: 111 for a history of myocardial infarction; 28 for scarring on echocardiography (regional akinesia/dyskinesia with thinning and/or increased brightness); 13 for previous revascularization procedures; 9 for aortic valve disease; 11 for a known cause of cardiomyopathy; and 35 for not undergoing angiography. The study group was therefore composed of 82 patients who were encouraged to perform maximal treadmill EE. EE criteria for ILVD were either impaired regional wall motion (RWM) or a decrease/no change in LVEF from baseline to peak exercise, while criteria for DC were RWM improvement/no change and LVEF increase. The ILVD group was formed by 39 patients with stenosis ≥ 70% diameter stenosis of a major epicardial coronary artery or major branch vessel. The remaining 43 patients constituted the DC group. Results. The number of coronary risk factors (ILVD 2.0 ± 1.1; DC 1.9 ± 1.1), baseline LVEF (ILVD 30 ± 7; DC 30 ± 8), and exercise-induced angina (ILVD 23%; DC 14%) did not differ between groups (p = NS). ILVD patients achieved less Mets (6.6 ±3.1 vs 8.3 ± 2.8; p < 0.05), had a lower heart rate x systolic blood pressure product (22 ± 5 vs 27 ± 7; p < 0.001), and developed regional and/or global LV dysfunction more frequently (79 vs 28%; p < 0.001). Sensitivity, specificity, positive and negative predictive values and global accuracy for ILVD detection were 79% (95% CI: 70-88), 72%

Long-Term Results With the Off-Label Use of Paclitaxel-Eluting Stents

Introduction and objectives. Little information is available about the results obtained with the off-label use of drug-eluting stents. Our aim was to investigate clinical findings on long-term follow-up. Methods. The study included 604 consecutive patients who received ≥ 1 paclitaxel-eluting stents (PES) at our catherization laboratory between June 2003 and February 2005. Patients were divided into 2 groups according to whether stent use was on-label or off-label as defined by current practice. The primary study endpoints were the combination of death and non-fatal acute myocardial infarction (AMI) and the combination of death, AMI and target-vessel revascularization (TVR). Secondary endpoints were these events individually and late stent thrombosis (ST). Results. During the median follow-up period of 34.3 months (interquartile range, 8.6 months), PESs had been used off-label in the majority of patients (ie, 464, 76.8% of the sample) and their use was associated with an increased risk of death or AMI (hazard ratio [HR]=2.2; 95% confidence interval [CI], 1.2-4) and of death, AMI or TVR (HR=1.8; 95% CI, 1.1-3). There was no significant difference in individual events (ie, death, AMI, or TVR). The group who used stents off-label had poorer clinical characteristics (ie, older age, and higher likelihoods of previous AMI or previous revascularization and multivessel disease), as well as a higher incidence of ST (5% vs 0; log-rank test, P=.015). Conclusions. The off-label use of PESs was associated with an increased risk of a combined clinical endpoint during long-term follow-up. Further studies are needed to determine the efficacy and safety of these devices in these settings.

Pronóstico a largo plazo del uso no aprobado de stents liberadores de paclitaxel

Introduccion y objetivos. Hay poca informacion sobre el pronostico del uso no aprobado de los stents farmacoactivos. Pretendimos evaluar sus resultados clinicos tras un seguimiento prolongado. Metodos. Se clasifico en dos grupos a los 604 pacientes consecutivos en quienes se implanto al menos 1 stent liberador de paclitaxel (SLP) entre junio de 2003 y febrero de 2005 en nuestra unidad de hemodinamica: uso aprobado y uso no aprobado, de acuerdo con las perspectivas actuales. Los variables principales del estudio fueron los combinados de muerte e infarto (IAM) y de muerte, IAM y revascularizacion de vaso tratado (RVT). Los componentes individuales y la trombosis del stent (TS) fueron otras variables en estudio. Resultados. Tras una mediana de seguimiento de 34,3 (RIQ, 8,6) meses, el uso no aprobado de los SLP fue mayoritario (464 pacientes, el 76,8% de la muestra) y se relaciono con un mayor riesgo de muerte o IAM (hazard ratio [HR] = 2,2; intervalo de confianza [IC] del 95%, 1,2-4) y de muerte, IAM o RVT (HR = 1,8; IC del 95%, 1,1-3). No hubo diferencias significativas en los eventos individuales (muerte, IAM y RVT). El grupo del uso no aprobado presento un peor perfil clinico (mayores edad y frecuencias de IAM o revascularizacion previos y de enfermedad multivaso), asi como una mayor incidencia de TS (el 5% frente a 0; log-rank, p = 0,015). Conclusiones. El uso no aprobado de los SLP se asocia con un elevado riesgo de eventos clinicos combinados tras un seguimiento a largo plazo. Son necesarios mas estudios para evaluar la eficacia y la seguridad de estos dispositivos en estas indicaciones.

An Application Framework for Building Evolutionary Computer Systems in Music

The authors present a musical composition model that creates rhythmic patterns through a system based on genetic algorithms, involving the interaction of several artificial musicians. In this environment, various composer systems and human musicians may interact within a system based on artificial life.

The shrinking human protein coding complement: are there now fewer than 20,000 genes?

Determining the full complement of protein-coding genes is a key goal of genome annotation. The most powerful approach for confirming protein coding potential is the detection of cellular protein expression through peptide mass spectrometry experiments. Here we map the peptides detected in 7 large-scale proteomics studies to almost 60% of the protein coding genes in the GENCODE annotation the human genome. We find that conservation across vertebrate species and the age of the gene family are key indicators of whether a peptide will be detected in proteomics experiments. We find peptides for most highly conserved genes and for practically all genes that evolved before bilateria. At the same time there is almost no evidence of protein expression for genes that have appeared since primates, or for genes that do not have any protein-like features or cross-species conservation. We identify 19 non-protein-like features such as weak conservation, no protein features or ambiguous annotations in major databases that are indicators of low peptide detection rates. We use these features to describe a set of 2,001 genes that are potentially non-coding, and show that many of these genes behave more like non-coding genes than protein-coding genes. We detect peptides for just 3% of these genes. We suggest that many of these 2,001 genes do not code for proteins under normal circumstances and that they should not be included in the human protein coding gene catalogue. These potential non-coding genes will be revised as part of the ongoing human genome annotation effort.

From Euler and Navier-Stokes equations to shallow waters by asymptotic analysis

In this paper, we study the Navier-Stokes and Euler equations in a domain with small depth. With this aim, we introduce a small adimensional parameter @e related to the depth. First we make a change of variable to a domain independent of @e and then we use asymptotic analysis to study what happens when @e becomes small. This way we obtain two new models for @e small that, after coming back to the original domain and without making a priori assumptions about velocity or pressure behaviour, give us a shallow water model including a new diffusion term (obtained from Navier-Stokes equations) and a shallow water model without viscosity and explicit dependence on depth (obtained from Euler equations).

A new shallow water model with linear dependence on depth

In this paper, we study the Euler equations in a domain with small depth. With this aim, we introduce a small adimensional parameter @e related to the depth and we use asymptotic analysis to study what happens when @e becomes small. Usually, when asymptotics are used to analyze fluids, they are used in the original domain or the surface is supposed to be constant. We, however, shall use the asymptotic technique making a change of variable to a reference domain independent of the parameter @e and the time. In this way we obtain a model for @e small that, after coming back to the original domain, gives us a shallow water model that considers the possibility of a non-constant bottom and the horizontal velocity components depend on z if the vorticity is not zero. This represents an interesting novelty with respect to shallow water models found in the literature. We stand out that we do not need to make a priori assumptions about velocity or pressure behavior to obtain the model. The new model is able to calculate exactly the solutions of Euler equations that are linear in z, whereas the classic model just obtains the averaged velocities.