AbstractStudies on the cognitive working mechanism of smoking cessation in high-risk populations are few and much needed, and identifying long-term psychosocial factors to smoking cessation are relevant to improve intervention for cardiac patient groups. This longitudinal study followed patients who smoked and suffered an acute coronary syndrome from hospitalization to 12 months after clinical discharge. Questionnaires were administered to assess nicotine dependence, behavioral dependence, autonomous self-regulation, perceived competence, social support, anxiety, depressive symptoms and meaning in life at baseline, six months and twelve months after clinical discharge. The results showed that anxiety (F(2, 62) = 28.10, p < .001, η_p² = .48) and depressive symptoms (F(2, 62) = 10.42, p < .001, η_p² = .25) decreased over time, whereas meaning in life (F(2, 61) = 44.77, p < .001, η_p² = .59) and social support increased (t(63) = –4.54, p < .001, 95% IC[–11.05, 4.29], η² =.25). Smoking dependence was negatively predicted by change in perceived competence (B = –2.25, p = .011, 95% IC[.02, .60]) and positively by change in depressive symptoms (B =.37, p = .042, 95% IC[1.01, 2.05]) 12 months after clinical discharge. Nicotine dependence (t(17) = 2.76, p = .014, 95% IC[.39, 2.94], η² =.31) and the number of cigarettes smoked per day (t(17) = 4.48, p < .001, 95% IC[5.49, 15.29], η² =.54) decreased over time, whereas behavioral dependence increased among smokers (t(17) = –2.37, p = .030, 95% IC[–4.30, 2.54], η² =.25). This study suggests that long term abstinence in cardiac patients may be enhanced by psychological interventions addressing perceived competence, depressive symptoms and behavioral dependence.