Recent advances in the mathematical models of electro-cardiology have prompted new requirements for computation. The computational challenges span from a detailed simulation of subcellular calcium handling, through a proper cell-tissue coupling, to a whole heart modeled on an unstructured computational mesh. The sheer size of the computation often can only be satisfied by cutting-edge computer clusters, where the main computing power is provided by non-conventional processors (also called accelerators), such as GPUs or many core processors. In this talk, we discuss the related issues of programming and performance engineering. The particular topics include CPU-accelerator computing, memory traffic minimization, and code vectorization.