Cardiac decompression and right ventricular function improvement after bar removal in patients with pectus excavatum.

Pectus excavatum, the most frequent malformation of the chest wall, has been related to cardiac compression and exercise intolerance. Cardiac outcomes after minimally invasive repair of pectus excavatum with retrosternal implants, particularly after removal (> 2 years postoperative) are generally unknown. We evaluated stress echocardiography outcomes before repair and after bar removal. This study comprised a retrospective cohort of patients with diagnosis of isolated pectus excavatum who underwent stress echocardiography before minimally invasive repair with retrosternal implants, and after bar removal. The diastolic function was evaluated by means of the trans tricuspid flow and tissue doppler imaging. The compression of the atrioventricular groove was assessed using the trans tricuspid gradient and the tricuspid area. We included 43 patients, with a mean age of 15.7 ± 4.0 years (91% male). After bar removal, 83% of patients referred improvement of exercise capacity. Furthermore, we found a significant improvement in right ventricular filling patterns, including a better E/A ratio profile during exercise (p = 0.001), lower filling pressures both at rest (p < 0.0001) and during exercise (p = 0.031), and lower rates of resting paradoxical septal motion [70% vs. 20%, p = 0.0007]. The trans tricuspid mean gradient during exercise was significantly lower after bar removal (p < 0.0001). In this study involving patients with minimally invasive repair of pectus excavatum, we demonstrated a beneficial impact of such intervention after bar removal, with significant improvements related to the right ventricular function, as well as signs of relief of cardiac compression.

Caracterización del tejido miocárdico a través de imágenes de densidad electrónica: relación con el sexo y factores de riesgo cardiovascular / Myocardial Tissue Characterization Using Electron Density Imaging: Relationship with Sex and Cardiovascular Risk Factors

RESUMEN Introducción. Las imágenes de densidad electrónica (DE) podrían detectar diferencias miocárdicas tisulares no distinguibles mediante la tomografía computarizada (TC) convencional sin contraste. Objetivos. Evaluar si existen diferencias de DE miocárdica asociadas al sexo, y de estar presentes, su relación con factores de riesgo cardiovascular o calcificación coronaria. Material y métodos. Los pacientes pertenecían a un estudio prospectivo observacional de centro único que incluyó sujetos asintomáticos entre 50 y 75 años, derivados para realizar una TC de tórax de baja dosis. Todas las imágenes se obtuvieron mediante un equipo de TC espectral dual, y fueron evaluadas utilizando imágenes de TC convencional (120 kVp) y de DE. Resultados. Se incluyó un total de 171 pacientes. La atenuación miocárdica no estuvo relacionada con el sexo o factores de riesgo coronarios (todos con p >0,05), mientras que el porcentaje de densidad electrónica respecto del agua (%EDW, por su sigla en inglés) fue significativamente mayor en la población masculina (p<0,0001), y en los pacientes con diabetes (p=0,007), hipertensión (p=0,004) y obesidad (p=0,004). La extensión de la calcificación coronaria no estuvo relacionada ni con la ate nuación ni con la DE miocárdicas. En el análisis univariado, el sexo masculino fue la única variable asociada a un %EDW elevado (p=0,011), mientras que la edad, la diabetes, la obesidad, el tabaquismo, la hipertensión y el score CACSIS (score de calcificación de las arterias coronarias), no. Un modelo de regresión logística que incluyó sexo, obesidad, diabetes e hipertensión, identificó al sexo masculino como el único predictor independiente de %EDW elevado (OR 2,51, IC 95% 1,23-5,34, p=0,016). Conclusiones. En este estudio, las imágenes de DE identificaron diferencias en el tejido miocárdico que la TC convencional fue incapaz de discriminar, con un mayor %EDW en hombres y en pacientes con factores de riesgo cardiovascular. El sexo masculino fue el único predictor independiente de %EDW elevado.

ABSTRACT Background. Electron density (ED) imaging might be able to detect myocardial tissue differences indistinguishable for con ventional non-contrast computed tomography (CT). Objectives. To evaluate whether there are differences in myocardial ED associated with sex, and if present, their relationship with cardiovascular risk factors or coronary calcification. Methods. Patients were participants of a prospective single center observational study comprising asymptomatic subjects between 50 and 75 years old, referred for a low-dose chest CT. All images were obtained using a dual-layer detector spectral CT, and evaluated using conventional CT (120 kVp) and ED images. Results. A total of 171 patients were included. Myocardial attenuation was not related to sex or coronary risk factors (all p >0.05), whereas the percent electron density relative to water (%EDW) was significantly higher among males (p <0.0001), and patients with diabetes (p = 0.007), hypertension (p = 0.004), and obesity (p = 0.004). The extent of coronary artery calcification was unrelated to neither the myocardial attenuation, nor the myocardial ED. At univariate analysis, male sex was the only variable associated with a high %EDW (p = 0.011), whereas age, diabetes, obesity, smoking, hypertension, and CACSIS (coronary artery calcification segment involvement score), were not. Logistic regression analysis including sex, obesity, diabetes, and hypertension in the model, identified male sex as the only independent predictor of a high %EDW (OR 2.51, 95%CI 1.23-5.34, p=0.016). Conclusions. In this study, ED imaging identified myocardial tissue differences that conventional CT was unable to discriminate, with a higher %EDW in men and in patients with cardiovascular risk factors. Male sex was the only independent predictor of a high %EDW

Pyrethroid resistance distribution in Triatoma infestans and environmental association along the Argentine endemic zone.

Insecticide resistance is considered a barrier to chemical control of Triatoma infestans, the main vector of Chagas disease in the Southern Cone of South America. Although initiatives to reduce the incidence of the disease in the region have integrated different strategies, they have mainly relied on vector elimination using pyrethroid insecticides such as deltamethrin. Reports of pyrethroid resistance in connection with T. infestans control failures first emerged in northern Argentina and southern Bolivia. Recently, a mosaic pyrethroid-resistant focus has been described in the center of the Argentine Gran Chaco (Department of General Güemes, Chaco Province), characterized by the presence of susceptible and very highly resistant populations in the same area. The involvement of different resistance mechanisms has been proposed, together with the contribution of environmental variables that promote the toxicological heterogeneity described. In the endemic zone of Argentina, however, new questions arise: Are there any other clusters of resistance? Is there a relationship between the distribution of resistance and environmental variables (as has been observed at smaller scale)? We studied toxicological data from insects collected and analyzed at 224 localities between 2010 and 2020 as part of the resistance monitoring conducted by the Chagas National Program. The sites were classified according to the survival rate of insects exposed to a discriminant dose of deltamethrin: 0-0.19 were considered susceptible, 0.2-0.79 low-resistance, and 0.8-1 high-resistance. Localities were georeferenced to describe the spatial distribution of resistance and to identify environmental variables (demographics, land use, urbanization, connectivity, and climate) potentially associated with resistance. We used Generalized Linear Models (GLMs) to examine the association between resistance and environmental predictors, selecting error distributions based on the response variable definition. For the entire period, 197 susceptible localities were distributed across the endemic zone. Localities with different survival rates were found throughout the area; 9 high-resistance localities circled the two previously identified resistant foci, and 18 low-resistance in 6 provinces, highlighting their relevance for control planning. Precipitation variables were linked to resistance in all the GLMs evaluated. Presence/absence models were the most accurate, with precipitation, distance from the capital city, and land use contributing to the distribution of resistance. This information could be valuable for improving T. infestans control strategies in future scenarios characterized by unpredictable changes in land use and precipitation.

Thrombus discrimination with electron density: potential implications for non-contrast computed tomography imaging.

The potential clinical usefulness of electron density (ED) imaging, that can be directly estimated using dual-layer spectral computed tomography (CT), has been poorly investigated. We explored whether ED imaging might improve thrombus identification compared to conventional imaging in vitro. We evaluated mechanical thrombectomy material obtained from patients with acute ischemic stroke (AIS) treated in a tertiary level stroke center and immediately fixed in 10% neutral buffered formalin and stored in polystyrene test tubes. The test tubes were immersed in a bucket of water for evaluation by spectral CT, along with scattered control tubes. All images were obtained using a dual-layer detector CT scanner. Each tube was assessed using multiparametric side-by-side view of conventional CT (120 kVp), low monoenergetic imaging (40 keV), and ED images. Fifty-eight polystyrene tubes were analyzed, comprising 52 tubes with thrombectomy material of at least 1 mm2 size obtained from 52 AIS patients, and six control tubes filled with formalin. ED imaging identified accurately the presence of material in all tubes, whereas 2 (3%) of the tubes containing thrombus were not identified by conventional CT, leading to a very good agreement between observers for the presence of material using conventional CT and ED imaging (kappa =0.84, P<0.001). Using ED imaging, thrombus material showed a mean density of 108.8±2.9 percent ED relative to water (%EDW), water had a mean density of 100.0±0.3 %EDW, and formalin a mean density of 103.5±1.2 %EDW. Compared to conventional imaging and 40 keV monoenergetic, ED imaging had a significantly higher signal-to-noise ratio (conventional 10.4±7.0, vs. 40 keV 11.5±8.4, vs. ED 490.0±304.5, P<0.001) and contrast-to-noise ratio (CNR) (conventional 4.3±4.3, vs. 40 keV 5.7±11.2, vs. ED 37.8±29.1, P<0.001). In this in-vitro study, we demonstrated improved visualization of thrombus with ED imaging compared to conventional imaging and low monoenergetic imaging, with a significant increase in CNR.

Unsophisticated assessment of the cardiopulmonary function in patients with pectus excavatum using the six minute walk test.

BACKGROUND: We explored whether the maximum predicted walking distance, assessed with six-minute walk test (6MWT) and reflecting submaximal functional exercise capacity, is decreased among patients with pectus excavatum (PEX). METHODS: This study comprised a retrospective analysis of patients with PEX who underwent a 6MWT for the assessment of functional capacity. The maximum distance walked was recorded and compared to reference values established for different populations, including a young and healthy South American population. RESULTS: We included 43 patients with PEX who underwent 6MWT. The mean age was 17.8 ± 6.7 years. The mean maximum distance walked was significantly lower than the predicted distance (600.8 ± 67.6 metres vs. 729.8 ± 67.5 metres, p < 0.0001). Using the Enright reference equation including an older reference population, the mean negative difference was higher (PEX patients walked 190.4 ± 78.4 metres less than predicted, p < 0.0001). We also applied the Li et al. reference equation accounting for sex among other variables, detecting a decreased walked distance compared to the gender-adjusted predicted distance (PEX patients walked a mean 222.4 ± 87.4 metres less than predicted, p < 0.0001). Using the Ulrich et al. equation, PEX patients walked a mean 114.2 ± 85.1 metres less than predicted (p < 0.0001). Although of uncertain clinical relevance, there was a significant decrease in the mean oxygen saturation after exercise (baseline 97.4 ± 1.2%, vs. final 96.4 ± 2.1%, p = 0.006). CONCLUSIONS: In this study, we identified a significant reduction in the maximum walked distance among patients with PEX compared to the predicted distance, thus potentially emerging as an unsophisticated means to evaluate and quantify functional exercise capacity.

The essential habitat role of a unique coastal inlet for a widely distributed apex predator.

Essential habitats support specific functions for species, such as reproduction, feeding or refuge. For highly mobile aquatic species, identifying essential habitats within the wider distribution range is central to understanding species ecology, and underpinning effective management plans. This study examined the movement and space use patterns of sevengill sharks (Notorynchus cepedianus) in Caleta Valdés (CV), a unique coastal habitat in northern Patagonia, Argentina. Seasonal residency patterns of sharks were evident, with higher detectability in late spring and early summer and lower during autumn and winter. The overlap between the residency patterns of sharks and their prey, elephant seals, suggests that CV functions as a seasonal feeding aggregation site for N. cepedianus. The study also found sexual differences in movement behaviour, with males performing abrupt departures from CV and showing increased roaming with the presence of more sharks, and maximum detection probability at high tide. These movements could be related to different feeding strategies between sexes or mate-searching behaviour, suggesting that CV may also be essential for reproduction. Overall, this study highlights the importance of coastal sites as essential habitats for N. cepedianus and deepens our understanding of the ecological role of this apex predator in marine ecosystems.

Platelet-Rich Fibrin in Third Molar Surgery: Systematic Review and Meta-Analysis Protocol.

Objective: The objective of this systematic review is to assess the effectiveness and safety of platelet-rich fibrin (PRF) in third molar surgery. Data Sources: A comprehensive search strategy is meant to be used in an attempt to identify all relevant randomized controlled trials (RCTs), ongoing investigation reported in specialty congresses and trials regardless of language or publication status (published, unpublished, in press and in progress). Searches will be conducted in the Cochrane Central Register of Controlled Trials (CENTRAL), PUBMED, Embase, Lilacs, the International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, US National Institutes of Health (NIH), grey literature and in specialized congresses and conferences. Eligibility Criteria: We will include randomized trials evaluating the effect of PRF on wound healing after third molar surgery. Two reviewers will independently screen each study for eligibility, data extraction and risk of bias assessment using Cochrane "risk of bias" tool. We will pool the results using meta-analysis and will apply the GRADE system to assess the certainty of the evidence for each outcome. Ethics and Dissemination: As researchers will not access information that could lead to the identification of an individual participant, obtaining ethical approval was waived.

Hyperacute Incidental Late Myocardial Enhancement in Ischemic Stroke Using Chest Spectral CT: Relationship with Etiology.

BACKGROUND: Hyperacute cardiac imaging of patients with acute ischemic stroke (AIS), though desirable, is impractical. Using delayed-enhancement, low-dose, non-gated, chest spectral computed tomography scans (DESCT), we explored the prevalence and patterns of incidental myocardial late iodine enhancement (LIE) and embolic sources, and their relationship with stroke etiology. METHODS: Since July 2020, DESCT was performed after cerebrovascular CT angiography (CTA) among patients with suspected AIS undergoing CT using a dual-layer spectral scanner, without additional contrast administration. Images were analyzed using monoenergetic reconstructions and iodine density maps, and the myocardial extracellular volume fraction (ECV, %) was calculated. RESULTS: Eighty patients with AIS were included. DESCT identified a cardiac thrombi in 6 patients (7.5%), and a complex aortic plaque in 4 (5%) cases; reclassifying 5 embolic strokes of uncertain source (28% of ESUS) to cardioembolic (CE, n = 3) and non-CE (n = 2) etiologies. LIE was identified in 38 (48%) patients, most commonly (82%) of ischemic pattern. We did not identify significant relationships between AIS etiology and the presence, pattern, and extent of LIE (p > 0.05); ECV (p = 0.56), severe aortic (p = 0.25) or valvular (p = 0.26) disease, or the extent of coronary calcification (p = 0.39). Patients with evidence of major cardiovascular DESCT findings had higher rates of all-cause death at 90 days (42% vs. 19%, p = 0.037). CONCLUSIONS: In this study, hyperacute cardiac imaging of AIS with DESCT identified a high prevalence of incidental cardiac disease predominantly involving LIE of ischemic etiology and mostly not related to the stroke etiology.

Usefulness of strain cardiac magnetic resonance for the exposure of mild left ventricular systolic abnormalities in pectus excavatum.

BACKGROUND: Systolic dysfunction in pectus excavatum (PEX) is usually very subtle and mainly focused on the right ventricle (RV), leading to normal or unremarkable cardiac imaging findings unless involving exercise stress. OBJECTIVES: We evaluated systolic function in PEX using longitudinal strain cardiac magnetic resonance (CMR), a validated parameter for the assessment of the systolic deformation of subendocardial fibers. METHODS: This prospective registry comprised consecutive patients with PEX who were referred to CMR to define treatment strategies or to establish surgical candidacy. We also included a control group of 15 healthy volunteers without chest wall abnormalities. Using dedicated software, we evaluated the endocardial global longitudinal strain (GLS) of both ventricles and the endocardial global circumferential strain (GCS) of the left ventricle (LV). RESULTS: A total of 50 patients with PEX comprised the study population, with a mean age of 19.9 ± 8.0 years. The right ventricular ejection fraction (RVEF) of patients with PEX was significantly lower compared to the control group both at end-expiration (59.5 ± 6.8 vs. 64.7 ± 4.7%, p = 0.008) and end-inspiration (56.7 ± 7.2%, vs. 62.7 ± 4.4, p = 0.004); as well as the pulmonary stroke distance (12.6 ± 2.5, vs. 15.0 ± 2.0 cm, p = 0.001). The LV volumetric analysis revealed no differences between PEX and the control group (p > 0.05 for all) regardless of the respiratory cycle, with a mean expiratory LV ejection fraction (LVEF) of 61.4 ± 6.0%. In contrast, the GLS of the LV was significantly lower in PEX compared to controls (-21.2 ± 3.2 vs. -23.7 ± 3.0%, p = 0.010), whereas GCS was similar either at expiration (-28.5 ± 4.0%, vs. -29.5 ± 2.8, p = 0.38) or inspiration (-29.3 ± 4.1%, vs.-28.9 ± 2.3, p = 0.73). CONCLUSIONS: In this study, we demonstrated that longitudinal strain analysis might enable the detection of very subtle left ventricular systolic function abnormalities in patients with PEX, that are commonly overlooked using the conventional assessment. LEVEL OF EVIDENCE: II.

Fluctuating asymmetry and exposure to pyrethroid insecticides in Triatoma infestans populations in northeastern Argentina

Exposure to sublethal doses of insecticide may affect biological traits in triatomines. We investigated the effects of toxicological phenotype (pyrethroid resistance status) and exposure to sublethal doses of deltamethrin on two traits of Triatoma infestans Klug (Heteroptera: Reduviidae) using a phenotypic plasticity experimental design. First-instar nymphs from 14 and 10 full-sib families from pyrethroid-susceptible and pyrethroid-resistant populations, respectively, were used. For the susceptible population, we treated first instars topically with acetone (control) or deltamethrin (treatment) once. For the resistant population, instars were treated once, twice and three times as first, third or fifth-instar nymphs, respectively. We measured cuticle thickness, wing size and wing shape of 484 emerging adults, and tested for treatment effects using mixed ANOVA and MANOVA models. Toxicological phenotype, exposure to deltamethrin and full-sib family exerted significant effects on cuticle thickness, wing size and wing shape. Adult triatomines previously treated with deltamethrin developed significantly thicker cuticles than control triatomines only in the resistant population and significantly bigger wings in both populations. Mean cuticle thickness and wing size increased with increasing exposures to deltamethrin. Exposure to sublethal doses of deltamethrin generated morphological modifications that may affect insect survival and flight dispersal, and hence may have evolutionary and epidemiological consequences.

Emerging role of spectral computed tomography in neurocardiology.

The complex and reciprocal relationship between the brain and the heart has gained increasing attention under the concept of neurocardiology. Myocardial injury is common in cerebrovascular disease, and cardiovascular complications are the second leading cause of death after stroke. Cardiac computed tomography (CT) is a fast and reliable non-invasive tool for the assessment of cardioembolic sources. Compared to single energy CT, spectral/dual energy cardiac CT improves tissue characterization and also leads to significant reductions in contrast volume. In this review article, we portray the potential clinical applications of spectral CT in neurocardiology, focusing in the enhanced diagnosis of cardioembolic sources and cardiovascular risk assessment of patients with stroke, including improved detection of thrombus, identification of subtle myocardial disease, and pulmonary complications within the same session.

Estado de la resistencia a insecticidas en Triatoma infestans de Argentina

Los insectos triatominos son los vectores de la enfermedad de Chagas. El control químico de estos insectos es la principal herramienta utilizada para reducir la incidencia de la enfermedad. Los piretroides son los principales insecticidas utilizados para el control de los triatominos en todos los países endémicos. La evolución de resistencia a insecticidas convierte en inefciente una exitosa estrategia de control químico. En Argentina se han detectado diferentes focos de resistencia en Triatoma infestans, el vector más importante en el Cono Sur de Sudamérica, asociados a defciencias en el control. Los estudios realizados sobre esta especie muestran que la resistencia es un problema complejo, ya que evolucionó en varias zonas de la distribución geográfca de la especie, se identifcaron diferentes mecanismos de resistencia, está asociada a modifcaciones en diversos procesos biológicos, está vinculada a variaciones ambientales y hay escasez de alternativas de control. En este manuscrito presentamos una revisión del conocimiento sobre la resistencia a piretroides en T. infestans en Argentina.

Utilidad de la TC espectral cardíaca para la evaluación de complicaciones trombóticas en pacientes con ataque cerebrovascular isquémico / Usefulness of Spectral Cardiac Computed Tomography for the Evaluation of Thrombotic Complications in Patients with Ischemic Stroke

RESUMEN Objetivo: Evaluar la utilidad de la angiotomografía computada (TC) espectral cardíaca en pacientes con ataque cerebrovascular isquémico (ACVi). Material y métodos: En el contexto de pandemia de COVID-19 incorporamos la utilización de la TC espectral cardíaca en pacientes con ACVi para descartar en una única sesión, tanto fuentes cardioembólicas (FCE) como la presencia de complicaciones trombóticas o daño miocárdico. A partir de julio de 2020 incorporamos una adquisición tardía a las TC cardíacas en contexto de ACVi. Se presentan cuatro casos representativos sobre su utilidad y hallazgos cardiovasculares. Resultados: Se presentan cuatro casos registrados en un lapso de 40 días. Dos pacientes con FCE (aorta y orejuela izquierda) y dos con ACVi de origen indeterminado donde se evidenció miocardiopatía (isquémica y no isquémica). Conclusiones: En el contexto del ACVi, la TC espectral cardíaca, que incluía adquisición tardía, permitiría, eventualmente, descartar la presencia de FCE e identificar la etiología subyacente.

ABSTRACT Objective: The aim of this study was to evaluate the usefulness of spectral cardiac computed tomography (CT) angiography in patients with ischemic stroke. Methods: In the setting of COVID-19 pandemic, we incorporated the use of spectral cardiac CT in patients with ischemic stroke to rule out the presence of cardioembolic sources, thrombotic complications or myocardial damage in a single session. Since July 2020, a delayed-phase image acquisition was incorporated to cardiac CT scans in the context of ischemic stroke. We describe four representative cases of the usefulness of the method and the cardiovascular findings. Results: We present four cases recorded recorded within a 40-day period. Two patients with patients with cardioembolic source (aorta and left atrial appendage) and two with ischemic stroke of undetermined source with evidence of cardiomyopathy (ischemic and non-ischemic). Conclusions: In the setting of ischemic stroke, spectral cardiac CT with delayed acquisition could be useful to rule out the presence of cardioembolic sources and identify the underlying etiology.

Genetic structure of deltamethrin-resistant populations of Triatoma infestans (Hemiptera: Reduviidae) in the Gran Chaco.

The genetic structure of natural populations offers insight into the complexities of their dynamics, information that can be relevant to vector control strategies. Microsatellites are useful neutral markers to investigate the genetic structure and gene flow in Triatoma infestans, one of the main vectors of Chagas disease in South America. Recently, a heterogeneous pyrethroid-resistant hotspot was found in the Argentine Gran Chaco, characterized by the highest levels of deltamethrin resistance found at the present time. We applied population genetics analyses to microsatellite and village data and search for associations between the genetic variability and the heterogeneous toxicological pattern previously found. We genotyped 10 microsatellite loci in 67 T. infestans from 6 villages with no, low, and high pyrethroid resistance. The most genetically diverse populations were those susceptible or with low values of resistance. In contrast, high-resistance populations had lower herozygosity and some monomorphic loci. A negative association was found between variability and resistant ratios. Global and pairwise FSTs indicated significant differentiation between populations. The only susceptible population was discriminated in all the performed studies. Low-resistance populations were also differentiated by a discriminant analysis of principal components (DAPC) and were composed mostly by the same two genetic clusters according to STRUCTURE Bayesian algorithm. Individuals from the high-resistance populations were overlapped in the DAPC and shared significant proportions of a genetic cluster. These observations suggest that the resistant populations might have a common origin, although more genetic markers and samples are required to test this hypothesis more rigorously.

Grasa epicárdica y esteatosis hepática como marcadores de riesgo cardiovascular / Epicardial Fat and Hepatic Steatosis as Cardiovascular Risk Markers

RESUMEN El tejido adiposo epicardico (TAE) es un tejido metabólicamente activo que ha cobrado gran interés en la última década como marcador de riesgo cardiovascular. El TAE se relaciona con la producción de citoquinas proinflamatorias y de ácidos grasos libres, con la promoción de un estado de hipercoagulabilidad, y con numerosos factores de riesgo cardiometabólico. Existe una íntima relación entre las arterias coronarias y el TAE, no solo anatómica, sino en cuanto a aspectos fisiológicos bidireccionales de regulación paracrina. Además, numerosos estudios han encontrado una relación entre el TAE y la presencia de disfunción endotelial, ateromatosis no obstructiva, estrés oxidativo, fibrilación auricular, y disfunción diastólica. En paralelo, existe una estrecha relación entre la esteatosis hepática (la enfermedad hepática crónica más frecuente), la ateromatosis coronaria, y el riesgo cardiovascular. Una de las características interesantes de la esteatosis hepática y diferenciales con respecto a la enfermedad coronaria es su carácter dinámico y, en cierta medida, reversible. A pesar de las asociaciones descriptas con la ateromatosis y con el riesgo cardiovascular, y de su evaluación sencilla a partir de métodos de imagen no invasivos, la grasa epicárdica y el hígado graso no alcohólico son raramente considerados como marcadores de riesgo en la práctica clínica.

ABSTRACT Epicardial adipose tissue (EAT) is a metabolically active tissue which has raised great interest in the last decade as a cardiovascular risk marker. It is related with the production of proinflammatory cytokines and free fatty acids, the promotion of a state of hypercoagulability and with numerous cardiometabolic risk factors. Between EAT and coronary arteries, there is not only an intimate anatomical association, but also bidirectional physiological aspects of paracrine regulation. In addition, several studies have found a relationship between EAT and endothelial dysfunction, non-obstructive atheromatosis, oxidative stress, atrial fibrillation and diastolic dysfunction. Parallel to these findings, there is a tight association between hepatic steatosis (the most prevalent chronic hepatic disease), coronary atheromatosis and cardiovascular risk. One of the interesting and differential characteristics of hepatic steatosis with respect to coronary artery disease is its dynamic, and to a certain point reversible, character. Despite their association with atheromatosis and cardiovascular risk and simple assessment from non-invasive imaging methods, epicardial fat and non-alcoholic fatty liver are seldom considered as risk markers in clinical practice.

Anatomic or functional testing in stable patients with suspected CAD: contemporary role of cardiac CT in the ISCHEMIA trial era.

One of the foundations of the management of patients with suspected coronary artery disease (CAD) is to avoid unnecessary invasive coronary angiography (ICA) referrals. However, the diagnostic yield of ICA following abnormal conventional stress testing is low. The ability of ischemia testing to predict subsequent myocardial infarction and death is currently being challenged, and more than half of cardiac events among stable patients with suspected CAD occur in those with normal functional tests. The optimal management of patients with stable CAD remains controversial and ischemia-driven interventions, though improving anginal symptoms, have failed to reduce the risk of hard cardiovascular events. In this context, there is an ongoing debate whether the initial diagnostic test among patients with stable suspected CAD should be a functional test or coronary computed tomography angiography. Aside from considering the specific characteristics of individual patients and local availability and conditions, the choice of the initial test relates to whether the objective concerns its role as gatekeeper for ICA, prognosis, or treatment decision-making. Therefore, the aim of this review is to provide a contemporary overview of these issues and discuss the emerging role of CCTA as the upfront imaging tool for most patients with suspected CAD.

Insecticide Resistance Mechanisms in Triatoma infestans (Reduviidae: Triatominae): The Putative Role of Enhanced Detoxification and Knockdown Resistance (kdr) Allele in a Resistant Hotspot From the Argentine Chaco.

Chagas disease affects around 6 million people in the world, and in Latin America, it is mainly transmitted by the kissing bug. Chemical control of the vector with pyrethroid insecticides has been the most frequently used tool to reduce the disease incidence. Failures of field control have been detected in areas of the Argentinian Gran Chaco that correlate with high levels of insecticide resistance. Here, we provide evidence of the mechanisms involved in the resistance to insecticides of field populations of T. infestans from General Güemes Department (Chaco Province, Argentina). The biochemical analysis suggests the increase in the activity of the degradative enzymes P450 oxidases and esterases as a minor contributive mechanism in low-resistance populations. The molecular study revealed high frequencies of the kdr L925I mutation at the voltage-gated sodium channel as responsible for the high resistance ratios detected. This knowledge contributes to the generation of comprehensive vector control strategies that reduce the incidence of the disease.