CAM: Computer-Assisted Manufacturing

doi:10.1007/978-3-030-65947-9_3

AutoresNicolás A. Rubio, Jorge M. Galante

Por qué importa

Este estudio explora las heterogeneidades en la perfusión y el metabolismo energético del miocardio ventricular izquierdo. Se observan diferencias significativas en el flujo sanguíneo y la utilización de energía entre áreas adyacentes, con patrones temporalmente estables. Las áreas de alto flujo muestran mayor captación de sustratos energéticos y un turnover más rápido del ciclo de Krebs, correlacionado con un mayor consumo de oxígeno. A pesar de la estrecha relación entre oferta y consumo de oxígeno, las áreas de bajo flujo no presentan signos bioquímicos de isquemia. Sin embargo, tras la interrupción del flujo, las áreas de alto flujo presentan mayor riesgo de infarto debido a su demanda energética elevada. Futuras investigaciones determinarán la base molecular de estas disparidades y su impacto en la contractilidad local, ofreciendo información relevante para comprender la fisiología tisular.

Abstract original

Within the left ventricular myocardium, substantial differences can be observed in terms of both perfusion and energy turnover. In addition to the small transmural gradient from the subepi--to the subendocardium (1:1.2), more recent high-resolution studies reveal a major patchwork-pattern, e.g., in terms of flow. Adjacent 200 microliters areas can differ more than 3-fold in local perfusion. Low flow and high flow areas (< 50% or > 150% of mean flow, respectively) represent up to 1/5 of the left ventricular myocardium. This local flow pattern is temporally stable for at least days and possibly weeks. Low and high flow areas also differ in local energy metabolism. High flow areas are characterized by enhanced glucose phosphorylation and fatty acid permeability, resulting in increased uptake of these substrates. This is the basis for the recent finding that high flow areas are characterized by an enhanced turnover of the citric acid cycle and thus of local O2 consumption. Since local O2 supply and consumption are closely coupled, low flow areas display no biochemical signs of ischemia. Reducing local flow by 50% results in a similar rise of adenosine or lactate in low and high flow areas. Following complete cessation of perfusion, high flow areas display a greater risk of infarction, indicating enhanced energy demand. Further studies are needed to elucidate the molecular basis of this spatial heterogeneity and to test whether the 3-fold differences in local energy turnover within the myocardial wall also translate into comparable variations of local contractility.

Leer texto completo ↗DOI · 10.1007/978-3-030-65947-9_3

Autor Doctor&Cols

Nicolás A. Rubio
Cirugía Oral e Implantología

Cómo citar

Rubio NA, Galante JM. CAM: Computer-Assisted Manufacturing. Digital Dental Implantology: From Treatment Planning to Guided Surgery (Springer). 2021. doi:10.1007/978-3-030-65947-9_3