Open-source software for generating electrocardiogram signals
  ECGSYN, a dynamical model that faithfully reproduces the main features of the human electrocardiogram (ECG), including heart rate variability, RR intervals and QT intervals is presented. Details of the underlying algorithm and an open-source software implementation in Matlab, C and Java are described. An example of how this model will facilitate comparisons of signal processing techniques is provided. 
Patrick E. McSharry and Gari D. Cifford