text: In this way, it has been possible to create a virtual cellular population of cardiomyocytes and vary their conductances that are related to the main ionic currents which contribute to the action potential morphology, reflective of a specific anatomical region of the heart.
  In order to create a stable population of cellular action potentials, the biomarkers have to be considered. During the years, several biomarkers have been developed to best characterize the instability of cellular action potentials. Few biomarkers are reported:
  *APD90: it represents the action potential duration when the phase of the repolarization is at 90%, so it is possible to associate to this value a time and it can be expressed as:
  *APD90: it represents the action potential duration when the phase of the repolarization is at 50%, so it is possible to associate to this value a time and it can be expressed as:
  *APD20: it represents the action potential duration when the phase of the repolarization is at 20%, so it is possible to associate to this value a time and it can be expressed as:
  *Triangulation: it is a measure of how triangular is an action potential, expressed as:
  *APA: it represents the action potential amplitude, expressed as:
  Many other can be used according to the needs of the research .