We present a new approach for the reconstruction of ischemic regions from only a few non-contact intracardiac recordings. Hence, it is desirable to exploit the spatio-temporal correlations contained in the data. To this end, we incorporate a time-dependent monodomain model of the cardiac electric activity into the inversion scheme. In order to take into account the electrophysiological alterations of ischemic regions, we also introduce appropriate variations of the model parameters. This approach allows us to perform the reconstruction of the affected regions successfully using only a few recording sites. The reconstruction process is based on level set techniques. Our numerical experiments in a bi-dimensional model of cardiac tissue validate our approach.