Luis Martin: Coordination of calcium alternans in ventricular Z-Planes due to recovery from inactivation of RyR2

Calcium is considered one of the most important ions involved in the intricate workings of the heart. The control of intracellular calcium is crucial to the process called excitation-contraction coupling, enabling the chambers of the heart to contract and relax. It is involved in some of the most common heart diseases, like cardiac disfunction and arrhythmias, so knowing how it behaves during the calcium homeostasis cycle, the process of self-regulation which takes place in every beat, it is crucial for medical purposes. If we want to understand the basic physiology of this organ it is important to study in detail how calcium moves through the various organelles of the myocyte in order to provoke this process. In this work, calcium fluxes will be studied in order to better understand the mechanisms of self-regulation of calcium concentrations in ventricular myocytes. It will require the understanding of the intracellular calcium dynamics and their interaction and influence in the different microdomains of the cell. Understand the roles of ryanodine receptors and sarcoplasmic reticulum as well as the different mechanisms to increase or reduce the concentration of this ion in the myocyte, and study how these mechanism affect to cytosolic calcium concentration, which at the end is the responsable of the cardiac response. We will study the formation of steady state solutions and how the NCX work for getting stable responses. In this way a subsequent study has been carried out by means of simulations using a z-plane ventricular model to observe how different variables affect calcium homeostasis.