Résumé
RESUMEN Introducción: Existe evidencia reciente que establecería a la hipoperfusión muscular como causa primaria de trastornos metabólicos en respuesta a la sobrealimentación. Esta concepción centrípeta del desarrollo de trastornos metabólicos podría implicar no solo alteraciones en la microvasculatura, sino también afectación en las arterias de conductancia. Objetivos: 1) Determinar la asociación entre diámetro basal de la arteria humeral (D-Hum) y la vasodilatación mediada por flujo (VDMF) 2) Analizar la asociación de ambos parámetros conforme aumenta de la masa corporal 3) Evaluar asociaciones entre el D-Hum/VDMF con componentes del síndrome metabólico (SM) 4) Evaluar la asociación independiente de ambas variables con el SM. Material y métodos: Se evaluaron 3493 pacientes. Se excluyeron pacientes < 18 y >80 años, con patología cardiovascular previa, insuficiencia renal crónica (IRC), colagenopatías, y tratados con estatinas. Se determinó presión arterial (PA), parámetros antropométricos y perfil metabólico, y se clasificó a los sujetos de acuerdo con la presencia de SM según AHA/NHLBI 2019. Se midieron D-Hum en mm y VDMF en %. Se analizó la asociación lineal entre D-Hum y VDMF y se analizaron ambas variables según decilos de índice de masa corporal (IMC). Se evaluaron asociaciones entre D-Hum/VDMF con la PA, glucemia (Glu), triglicéridos (TG) y colesterol de alta densidad (HDLc). Se realizaron dos regresiones logísticas con SM como variable dependiente y D-Hum o VDMF más edad, sexo, IMC y factores de riesgo coronario (FRC) como independientes. Resultados: Ingresaron 1995 pacientes (48,2 ± 11 años, 56 % hombres). El D-Hum y la VDMF presentaron una asociación inversa (r= -0,42; p < 0,0001). El D-Hum aumentó según decilos del IMC (p < 0,000001); la VDMF mostró relación inversa con los decilos crecientes de IMC (p < 0,000001). El D-Hum presentó correlación directa con PA, Glu y TG; e inversa con HDLc (p < 0,05 en todos los casos). La VDMF mostró correlación inversa con PA, Glu y TG; y directa con HDLc (p < 0,05 en todos los casos). El D-Hum se asoció en forma independiente con el SM ajustado por edad, sexo, IMC y FRC (OR 1,42, p = 0,0019), mientras que la VDMF no (OR 0,98, p = 0,217). Conclusión: El remodelado vascular excéntrico se asoció con un compromiso en la adaptación vascular ante aumentos en la demanda de flujo sanguíneo y con alteraciones metabólicas a lo largo del incremento de la masa corporal. Así, el compromiso dinámico de la vasculatura podría tener un rol determinante en el desarrollo de alteraciones metabólicas en forma sincrónica con la ganancia de peso.
ABSTRACT Background: Recent evidence would establish muscle hypoperfusion as the primary cause of metabolic disorders in response to overfeeding. This centripetal concept on the development of metabolic disorders could involve not only alterations in the microvasculature, but also affect the conductance arteries. Objectives: The aim of this study was 1) to determine the association between baseline brachial artery diameter (BAD) and flow-mediated vasodilation (FMVD), 2) To analyze the association of both parameters throughout the increase in body mass, 3) To evaluate associations between BAD/FMVD with components of the metabolic syndrome (MS) and 4) To evaluate the independent association of both variables with MS. Methods: A total of 3493 patients were evaluated. Patients <18 and >80 years old, those with previous cardiovascular disease, chronic kidney disease (CKD), collagenopathies, or treated with statins were excluded from the study. Blood pressure (BP), anthropometric parameters and metabolic profile were determined, and the subjects were classified according to the presence of MS conforming AHA/NHLBI 2019 criteria. BAD was measured in mm and FMVD as percentage. The linear association between BAD and FMVD was assessed, and both variables were analyzed according to deciles of body mass index (BMI). Associations between BAD/FMVD with BP, glucose (Glu), triglycerides (TG) and high-density cholesterol (HDL-C) levels were evaluated. Two logistic regression analyses were performed with MS as dependent variable and BAD or FMVD plus age, gender, BMI, and coronary risk factors (CRF) as independent variables. Results: A total of 1995 patients (48.2 ± 11 years, 56% men) were admitted in the study. An inverse correlation was found between BAD and FMVD (r= -0.42; p < 0.0001). BAD increased according to deciles of BMI (p < 0.000001), while FMVD showed an inverse relationship with increasing deciles of BMI (p < 0.000001). BAD exhibited a direct correlation with BP, Glu and TG; and an inverse relationship with HDL-C (p < 0.05 in all cases). FMVD presented an inverse correlation with BP, Glu and TG; and a direct correlation with HDL-C (p < 0.05 in all cases). BAD was independently associated with MS adjusted for age, gender, BMI and CRF (OR 1.42, p=0.0019), while FMVD was not (OR 0.98, p = 0.217). Conclusion: Eccentric vascular remodeling was associated with vascular adaptation to increased blood flow demand and with metabolic alterations throughout the increase in body mass. Thus, the dynamic compromise of vasculature could play a decisive role in the development of metabolic alterations occurring synchronously with weight gain.
Résumé
Myasthenia gravis is an acquired autoimmune disorder of the neuromuscular junction characterized by fluctuating weakness and fatigability of skeletal muscles. The diagnosis can be established by clinical and serologic testing, with predominance of autoantibodies against the acetylcholine receptor, and Muscle-specific kinase antibodies. We report two cases of Myasthenia gravis, the first one is a 31 year old patient with a debut of the disease, mainly with bulbar symptoms, and the second one is a 29 year old patient diagnosed with generalized Miasthenia Gravis also mainly with bulbar symptoms with worsening of symptomatology. In this report treatments alternatives and management approaches are discused