In this talk, we will talk about the fascinating discovery stating that the equilibrium configuration displayed by cardiac fibers might be driven by the same mathematical models that govern the behavior of liquid crystals, which is a particularly adequate theory to describe the singularities observed in cardiac fiber orientation, such as the one present in the apex of the left ventricle. This kind of behavior has been also observed experimentally, a fact that was unknown during the development of this work and a remarkable validation for this theory. The mathematical model that we propose for the left ventricle is the Oseen-Frank system, which coincides in simple cases with the energy principle describing harmonic maps. For this model, we have done several theoretical and numerical validations, with the addition of a scalable solver for its usage in the context of large-scale simulations. In this talk we will show how this modeling framework arises, together with its limitations, how we plan to extend it to the rest of the heart, and several numerical tests that validate this framework. Some ongoing work regarding the mathematical structure of the model, extensions to the p-Laplacian and tensor models will be briefly addressed at the end. This work is being developed in collaboration with Axel Osses, Arturo Muñoz, and Cristóbal Ramos from Universidad de Chile and Manuel Sánchez, and Diego Vera from Pontificia Universidad Católica de Chile.