Talk:Forward problem of electrocardiology

Latest comment: 3 years ago by Majorett in topic Observations and suggestions for improvements

[Untitled] edit

"The problem to recover the extracellular potential with the no intracellular current across the epicardium boundary condition" I cannot understand what the bold part means. Moreover, in the final part, what P Q R S T refer to?

GiuliaMaffeis (talk) 13:32, 26 June 2020 (UTC)Reply

the no intracellular current means that there is not current from the intracellular region that can flow through the epicardium. In this model the current are divided in intracellular, extracellular and extramyocardial (this last one is the one in the torso). Physically they are the same, but formally, on what regard this problem, they are different.

P,Q,R,S,T are the way the peaks of the ECG are defined, as it is mentioned. In the second image of the article you can find a scheme about it.

User:Katje95 (talk) 15:51, 26 June 2020 (UTC)Reply

Observations and suggestions for improvements edit

The following observations and suggestions for improvements were collected, following expert review of the article within the Science, Tecnology, Society and Wikipedia course at the Politecnico di Milano, in June 2020.

  • is typicalli solved by means of -> is typically solved by means of
  • the heart electrical activity independently from the problem on the torso -> the heart electrical activity independently of the problem on the torso
  • exitation wave along the muscle fibers -> excitation wave along the muscle fibers
  • "Between the mathematical model on the macroscopic level". I would delete this part
  • bidomain model are obtained throught the assumption -> bidomain model are obtained through the assumption
  • Section Bidomain model, boundary condition: this is only one condition, you need two since you have two PDEs, see e.g. Quarteroni A., Manzoni A., Vergara C., The Cardiovascular System: Mathematical Modeling, Numerical Algorithms, Clinical Applications. Acta Numerica, 26, 2017, pag 454
  • which means that the current flows in the same way in all directions -> which means that the current flows is the same way in all directions
  • "or can be uncoupled, if the heart electrical model and the torso model are solved separately with a limited or imperfect exchange of information between them". This is a choice at the numerical level, at the mathematical continuous level, the two problems are always coupled
  • that establish a relationship between the extracellular potential and the torso potential -> that establish a relationship between the extracellular potential and the torso potential at the interface \Sigma
  • This equations ensure the continuity of both the potential and the current across the epicardium -> This equations ensure the continuity of both the potential and the current flux across the epicardium
  • Using these boundary conditions, it is possible to obtain two different fully coupled heart-torso models -> Using these interface conditions, it is possible to obtain two different fully coupled heart-torso models
  • Unfortunately, from the numerical viewpoint, the two models are computationally very expensive and have similar computational costs -> From the numerical viewpoint, the two models are computationally very expensive and have similar computational costs
  • Alternative boundary conditions -> Alternative interface conditions
  • Boundary conditions that represent a perfect electrical coupling -> The interface conditions introduced above that represent a perfect electrical coupling
  • and the resistive Rp effect that the pericardium has, alternative boundary conditions -> and the resistive effect Rp induced by the pericardium, alternative interface conditions
  • A possible simplification is provided by the so called uncoupled assumption -> A possible simplification at the numerical level is provided by the so called uncoupled assumption
  • Applying this equation to the boundary conditions of the fully coupled models, it is possible to obtained two uncoupled heart-torso models, in which the electrical models can be solved separately from the torso model reducing the computational costs -> Applying this boundary condition to the monodomain or bidomain problem, it is possible to obtained two uncoupled heart-torso models, in which the electrical models can be solved separately from the torso model reducing the computational costs at the expense of a splitting error.

The boundary condition for the torso should be specified. I suppose ut = ue. IN any case this a numerical choice, maybe it would be better to move it in the section Numerical methods

  • Sect Bidomain model: a mention to the physical meaning of g and of the ODE system should be reported

Majorett (talk) 17:27, 18 July 2020 (UTC)Reply