RESUMEN
El endotelio vascular controla la homeostasis del tono vascular, permeabilidad, coagulación, fibrinólisis, proliferación celular y la respuesta antiinflamatoria. En presencia de factores de riesgo cardiovascular aparece un cambio fenotípico en las células endoteliales hacia un perfil inflamatorio, situación que se conoce como disfunción endotelial. La diabetes mellitus, especialmente en el contexto del síndrome metabólico, origina disfunción endotelial con incremento de factores oxidantes, vasoconstrictores, proliferativos y procoagulantes. La disfunción endotelial guarda una estrecha relación con la presencia y evolución de la microalbuminuria en la diabetes mellitus y con la aparición de eventos cardiovasculares. La disfunción endotelial precede a las complicaciones de la aterotrombosis y se puede considerar un objetivo terapéutico para retrasar dichas complicaciones. En este artículo se revisa la fisiopatología de la disfunción endotelial, con especial atención a su relación con la diabetes mellitus, la metodología diagnóstica y las posibles vías de actuación terapéutica
The vascular endothelium controls vascular tone homeostasis, permeability, coagulation, fibrinolisis, cellular proliferation and anti-inflammatory response. In the presence of cardiovascular risk factors, a phenotypic change, known as endothelial dysfunction, appears in endothelial cells, which leads to an inflammatory profile. Diabetes disease, especially in the context of the metabolic syndrome, causes endothelial dysfunction which is associated with an increase of oxidant, vasoconstrictor, proliferative and procoagulant factors. Endothelial dysfunction has a closed relationship with the development and progression of microalbuminuria and other vascular events in patients with diabetes mellitus. Furthermore, endothelial dysfunction occurs before atherothrombotic complications are present and might be considered as a therapeutic target to prevention/retardation of these complications. In this work, we review the physiopathology of endothelial dysfunction, especially in association with diabetes mellitus, diagnostic methodology and different ways for therapeutic action
Asunto(s)
Humanos , Endotelio Vascular/fisiopatología , Diabetes Mellitus/fisiopatología , Estrés Oxidativo/fisiología , Vasodilatación , Factores de Riesgo , Permeabilidad Capilar , Sistema Vasomotor/fisiopatología , Embolia por Colesterol/fisiopatologíaRESUMEN
Two cases of bidirectional tachycardia are presented. The ventricular origin of these arrhythmias was assessed by His bundle recordings. Because of the V1 morphology of the ventricular complexes during tachycardia in one case and the unknown etiology in the other, these arrhythmias were considered to be atypical. The involved mechanisms and the causes inducing these tachycardias are discussed. Whatever the involved mechanism, our cases reaffirm the opinion that the terminology bidirectional tachycardia should be used only to describe an electrocardiographic pattern that may be caused by different electrophysiological mechanisms.