Epicardial fat is closely related to blood supply vessels, both anatomically and functionally, which is why any change in this adipose tissue's behavior is considered a potential risk factor for cardiovascular disease development. When proinflammatory adipokines are released from the epicardial fat, this can lead to a decrease in insulin sensitivity, low adiponectin production, and an increased proliferation of vascular smooth muscle cells. These adipokines move from one compartment to another by either transcellular passing or diffusion, thus having the ability to regulate cardiac muscle activity, a phenomenon called vasocrine regulation. The participation of these adipokines generates a state of persistent vasoconstriction, increased stiffness, and weakening of the coronary wall, consequently contributing to the formation of atherosclerotic plaques. Therefore, epicardial adipose tissue thickening should be considered a risk factor in the development of cardiovascular disease, a potential therapeutic target for cardiovascular pathology and a molecular point of contact for “endocrine-cardiology.”

Cardiac muscle contraction is a strictly regulated process which conjugates a series of electrophysiological, biochemical and mechanic events, resulting in the pumping of blood to all bodily tissues. These phenomena require a very high energetic demand both for generating the necessary mechanical force, and for maintaining cellular homeostasis during the process. In the myocardium, fatty acids (FA) represent the main energy substrate, although other secondary substrates, such as glucose and ketone bodies, may also be used. Nevertheless, under certain conditions such as heart failure or myocardial ischemia, FA metabolism may become deleterious via mechanisms such as oxidative stress and arrhythmogenesis. In an ischemic milieu, various metabolic changes occur as a consequence of hypoxia, favoring cell necrosis, ventricular arrhythmias, and death. Major events in this context include an increase in extracellular K + , a decrease in pH, and accumulation of intracellular calcium. This review includes a detailed description of the molecular basis underlying myocardial contraction and energetic metabolism in cardiomyocytes, aiming to promote an integral understanding of the pathophysiology of heart ischemia. This in turn may aid in the development of future, more satisfactory alternative treatments in the management of acute coronary ischemia episodes.

How to cite this article: Calvo MJ, Martínez MS, Torres W, Chávez-Castillo M, Luzardo E, Villasmil N, Salazar J, Velasco M, Bermúdez V. Omega-3 polyunsaturated fatty acids and cardiovascular health: a molecular view into structure and function. Vessel Plus 2017;1:116-28.Given the notorious impact of cardiovascular disease (CVD) as the current leading cause of mortality worldwide, the prevention, identification and management of CV risk factors represents a priority in daily clinical practice. Several studies have shown the beneficial effects of dietary omega-3 polyunsaturated fatty acids (PUFAs) on CV health. Their derivatives, eicosapentaenoic acid and docosahexaenoic acid, intervene in multiple metabolic pathways, including: regulation of the inflammatory response, by reducing the synthesis of pro-inflammatory cytokines; regulation of platelet aggregation, activation and adhesion, by modulating thromboxane A2 and plasminogen activator inhibitor-1 activity; regulation of the coagulation pathways, by reducing the carboxylation of vitamin K-dependent coagulation factors; improvement of endothelial function, given their effects on prostaglandin synthesis and endothelial nitric oxide synthase; reduction of serum lipids, through their effects on the hepatic synthesis of triacylglycerides, beta-oxidation of fatty acids and lipoprotein catabolism; and improvement of myocardial function via their membrane-stabilizing effects, and an increase in fluidity, size and distribution of membrane lipid rafts. Nevertheless, these effects appear to vary according to the type of PUFA ingested, dietary sources, daily dosing and individual factors inherent to the subject. Therefore, further studies are required to determine the ideal supplementation for each kind of patient and their particular CV profiles. Key words:Cardiovascular disease, omega-3 polyunsaturated fatty acids, eicosapentaenoic acid, docosahexaeonic acid ABSTRACTArticle history:

Insulin resistance (IR) evaluation is a fundamental goal in clinical Background: and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. This is a sub-study of Maracaibo City Metabolic Syndrome Methods: Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2.The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. Results: female: 4.56±0.33, p=8.93x10 ). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001).The TGI is a measure of interest to identify IR in the general Conclusions: population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Insulin resistance (IR) evaluation is a fundamental goal in clinical Background: and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. This is a sub-study of Maracaibo City Metabolic Syndrome Methods: Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2.The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. Results: female: 4.56±0.33, p=8.93x10 ). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001).The TGI is a measure of interest to identify IR in the general Conclusions: population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

Background: Insulin resistance (IR) evaluation is a fundamental goal in clinical and epidemiological research. However, the most widely used methods are difficult to apply to populations with low incomes. The triglyceride-glucose index (TGI) emerges as an alternative to use in daily clinical practice. Therefore the objective of this study was to determine an optimal cutoff point for the TGI in an adult population from Maracaibo, Venezuela. Methods: This is a sub-study of Maracaibo City Metabolic Syndrome Prevalence Study, a descriptive, cross-sectional study with random and multi-stage sampling. For this analysis, 2004 individuals of both genders ≥18 years old with basal insulin determination and triglycerides < 500 mg/dl were evaluated.. A reference population was selected according to clinical and metabolic criteria to plot ROC Curves specific for gender and age groups to determine the optimal cutoff point according to sensitivity and specificity.The TGI was calculated according to the equation: ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2. Results: The TGI in the general population was 4.6±0.3 (male: 4.66±0.34 vs. female: 4.56±0.33, p=8.93x10 -10). The optimal cutoff point was 4.49, with a sensitivity of 82.6% and specificity of 82.1% (AUC=0.889, 95% CI: 0.854-0.924). There were no significant differences in the predictive capacity of the index when evaluated according to gender and age groups. Those individuals with TGI≥4.5 had higher HOMA2-IR averages than those with TGI <4.5 (2.48 vs 1.74, respectively, p<0.001). Conclusions: The TGI is a measure of interest to identify IR in the general population. We propose a single cutoff point of 4.5 to classify individuals with IR. Future studies should evaluate the predictive capacity of this index to determine atypical metabolic phenotypes, type 2 diabetes mellitus and even cardiovascular risk in our population.

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Introducción: La inactividad física es un problema de salud pública asociado a enfermedades crónicas no transmisibles. Determinar la prevalencia general y por esferas de inactividad física, y su asociación con factores cardiometabólicos. Métodos: Estudio transversal que incluyó 2 230 individuos adultos de ambos sexos de la ciudad de Maracaibo. Para la evaluación de la actividad física se aplicó la versión larga del Cuestionario internacional de actividad física, definiéndose la inactividad física como <600 MET-minutos/semana, se realizó un análisis de regresión logística multivariante para cada dominio. Resultados: La mayor prevalencia de inactividad física fue en la esfera de transporte (80,3 %), seguida de la esfera de trabajo (79,9 %), ocio (76,8 %) y hogar (47,9 %). En las 3 primeras esferas la inactividad física fue más frecuente en mujeres y la mayoría de sujetos fueron inactivos en 3 o 4 esferas simultáneamente. Las variables asociadas con inactividad física en ocio fueron el sexo femenino, edad >30 años, grupo étnico arábigo-asiático y estatus de exfumador; en la esfera transporte fueron el sexo femenino, sobrepeso y obesidad; en la esfera trabajo fueron el sexo femenino, edad ≥50 años, estatus educativo de secundaria, condición laboral de empleado y diabetes mellitus tipo 2; en la esfera hogar fueron el sexo masculino, estrato socioeconómico II-IV y la condición laboral de empleado. Conclusión: Existe una alta prevalencia de inactividad física en los habitantes de la ciudad de Maracaibo, por lo que es necesaria la promoción del ejercicio.