In this research, an automatic technique to segment the left ventricle from the heart information in multislice computed tomography images is proposed. A preprocessing stage is considered as a necessary preliminary task for diminishing the artifacts impact in the image analysis. With this idea, a similarity enhancement that combines a smoothed version of the original volume with a processed volume using mathematical morphology is used. This preprocessing approach is compared with respect to other strategies. After, a volume-of-interest is defined in order to isolate the cavity using two cropping planes detected with least squares support vector machines. Finally, the segmentations are obtained using both a region growing algorithm and a level sets algorithm. The robustness of each enhancement strategy is validated by performing the segmentation of images. This evaluation considered the Dice score, and both volume and surface errors. A clinical dataset from 12 patients is used in the inter- and intra subject evaluation. During intra-subject validation the proposed scheme achieves the best results, while a modified version of this scheme achieved the best performance during inter-subject validation.