In this paper, we propose a low-complexity receiver for frequency selective multiple-input multiple-output channels. We consider a List-type MAP equalizer which is a state-reduction algorithm of the MAP algorithm using per-survivor technique. In order to concentrate the energy on the channel first taps, we propose to use a whitened matched filter (WMF), as a prefilter to the equalizer. We also study the impact of channel estimation errors on our two-steps receiver performance. Using the results given by Gorokhov, we provide an approximation of the SNR loss caused by the channel estimation errors.