Cardiac rehabilitation is the sum of psychological, physical and social treatments that are offered to cardiac patients to maintain or regain an active position in society. This study wants to evaluate changes in the perception of the illness and in the self-efficacy of the management of positive and negative emotions in patients who went through cardiac rehabilitation. Sixty-seven patients (20 females, 47 males) were selected within the cardiac rehabilitation unit in the Hospital of Cittadella (Italy). Illness Perception Questionnaire - revised version and the Scale for the self-efficacy of the management of positive and negative emotions were submitted at the beginning and at the end of the rehabilitation program. One-way analyses-of-variance were performed to evaluate different answers in questionnaires between pre- and post-evaluation, and to explore gender differences. A significant change was found in the perception of duration of illness, perceived as permanent and longer after the cardiac rehabilitation program. Furthermore, at the end of the cardiac rehabilitation program men perceived the illness more chronic than women, even if they are less worried and anxious. Intensive cardiac rehabilitation has a great emotional impact on cardiac patients, influencing their perception and management of the illness. Working on emotions, through psychological groups, helps patients change their beliefs by offering them a different perspective to approach the illness.