Proinflammatory Cytokines Are Soluble Mediators Linked with Ventricular Arrhythmias and Contractile Dysfunction in a Rat Model of Metabolic Syndrome.

Metabolic syndrome (MS) increases cardiovascular risk and is associated with cardiac dysfunction and arrhythmias, although the precise mechanisms are still under study. Chronic inflammation in MS has emerged as a possible cause of adverse cardiac events. Male Wistar rats fed with 30% sucrose in drinking water and standard chow for 25-27 weeks were compared to a control group. The MS group showed increased weight, visceral fat, blood pressure, and serum triglycerides. The most important increases in serum cytokines included IL-1ß (7-fold), TNF-α (84%), IL-6 (41%), and leptin (2-fold), the latter also showing increased gene expression in heart tissue (35-fold). Heart function ex vivo in MS group showed a decreased mechanical performance response to isoproterenol challenge (ISO). Importantly, MS hearts under ISO showed nearly twofold the incidence of ventricular fibrillation. Healthy rat cardiomyocytes exposed to MS group serum displayed impaired contractile function and Ca2+ handling during ISO treatment, showing slightly decreased cell shortening and Ca2+ transient amplitude (23%), slower cytosolic calcium removal (17%), and more frequent spontaneous Ca2+ release events (7.5-fold). As spontaneous Ca2+ releases provide a substrate for ventricular arrhythmias, our study highlights the possible role of serum proinflammatory mediators in the development of arrhythmic events during MS.

A visual approach for the accurate determination of echocardiographic left ventricular ejection fraction by medical students.

BACKGROUND: Previously published reports show that there is significant intraobserver, interobserver, and interinstitutional variability in the determination of left ventricular (LV) ejection fraction (EF) by echocardiography. With the increased deployment of echocardiography (eg, handheld devices), there exists a need for developing a simple, intuitive approach for evaluating LVEF that allows a wider range of physicians to accurately and rapidly determine LVEF. OBJECTIVE: We sought to create a system for assessing LVEF that relies on recognition and matching of patterns, rather than on mathematic calculations and geometric assumptions. METHODS: A library of videoclips of cardiac function was compiled from 54 patients who spanned the spectrum of LVEF. LVEFs were calculated for these patients using standard echocardiographic methods, with further validation of a subsample using cardiac magnetic resonance imaging measurement of LVEF. The library of images was used to create a software tool for assessing LVEF on the basis of a "template-matching" approach. The software tool was then tested on medical students (N=13) to determine whether it enabled relatively untrained individuals to make accurate LVEF estimates. RESULTS: Using a template-matching approach for interpretation of echocardiograms, medical students were able to accurately estimate LVEF after only a limited introduction to echocardiography. Their LVEF estimates showed good correlation and agreement with gold standard (r = 0.88, standard square of the estimate = 6.0, limits of agreement = +12.0%, -15.6%). CONCLUSIONS: A new visual approach for assessing cardiac function using template matching can accurately estimate LVEF. With minimal training, medical students can make LVEF estimates that correlate well with gold standard. The application of this new approach includes allowing for the interpretation of LVEF from echocardiograms to be performed by a broader spectrum of physicians.

Real-time color-flow CMR in adults with congenital heart disease.

CMR is valuable in the evaluation of congenital heart disease (CHD). Traditional flow imaging sequences involve cardiac and respiratory gating, increasing scan time and susceptibility to arrhythmias. We studied a real-time color-flow CMR system for the detection of flow abnormalities in 13 adults with CHD. All 16 congenital flow abnormalities previously detected by echocardiography were visualized using color-flow CMR, including atrial septal defects (n = 4), ventricular septal defects (n = 9), aortic coarctation (n = 1), Blalock-Taussig shunt (n = 1) and Fontan shunt (n = 1). Real-time color-flow CMR can identify intra- and extra-cardiac flow abnormalities in adults with congenital heart disease.

Análisis del tiempo de reperfusión entre angioplastía primaria y trombolisis: Exito vs tiempo / Comparative analysis of reperfusion time in primary angioplasty vs thrombolisis. Success vs time

Se estudiaron 398 pacientes con diagnóstico de infarto agudo del miocardio, que ingresaron en las primeras 6 hrs de iniciado el evento y que fueron tratados con trombolisis o angioplastía primaria. Se dividieron en dos grupos: Grupo 1 (n=198) aquellos que recibieron trombolisis con estreptocinasa a dosis de 1'500,000 unidades en infusión por 60 min y Grupo 2 (n=200) aquellos sometidos a ACTP primaria. En el Grupo 1 el tiempo "dolor-puerta" fue de 3.7 ñ 1.7 Hrs y en el Grupo 2 de 3.8 ñ 2.4 Hrs (p=NS). El tiempo "puerta-aguja" fue de 48 ñ 12 min y el tiempo "puerta-balón" fue de 84 ñ 30 min (p< 0.001). El 77.6 por ciento de los pacientes sometidos a trombolisis tuvieron criterios clínicos de reperfusión. De los 144 pacientes con criterios clínicos de reperfusión, 58 pudieron ser llevados a coronariografía de control en las primeras 72 hrs, observándose flujo TIMI 3 en la arteria responsable del infarto en 24 pacientes (45.3 por ciento). La tasa de reperfusión exitosa para la ACTP fue de 85.5 por ciento. Conclusión: la reperfusión de logró realizar en un menor periodo de tiempo con trombolisis en comparación con angioplastía, sin embargo esta última logró obtener un mayor flujo TIMI 3