At present, the cardiovascular diseases (CVD) are among the major concerns of World Health Organization (WHO), assurance health systems and researchers in the specific field, because they are the number one cause of deaths globally, and according to several perspective studies, they will become the pathology that generates the greatest economic burden worldwide, through morbidity, disability, poor quality of life, and cause of death. Nowadays, the psychic field and the vulnerability of individual mental level to stress are an important link in the development of mental illness, CVD (included in the group of psychosomatic disorders), and also of interrelationship between them. The combined effects of these factors are reflected in the behavioral and cardiovascular (CV) system's pathophysiological changes, which determine the impairment of health-related quality of life for the CV patients, on both short-term and long-term. This chapter aims to address both the interrelationship of psychosocial factors with CVD in terms of its multifactorial etiology and the mark of this bidirectional link on the quality of life of the patients. In several sections, the following issues will be described: general aspects regarding the relationship between homeostasis-stress-pathology; the role of stress as a psychosocial factor in the multifactorial etiology of CVD; the implications of mental disorders in the pathogenesis of CVD; behavioral aspects of CV patient during his illness, and strategies for improving therapeutic adherence and the quality of life of these patients.