Background: Although there is preliminary evidence that alexithymia may influence the course of coronary heart disease (CHD), there are no studies exploring attempts to modify alexithymic characteristics in cardiac patients. Method: Twenty post-myocardial infarction (MI) patients (19 men and 1 woman) were placed in a treatment group, which received weekly group psychotherapy for 4 months. Seventeen post-MI patients (16 men and 1 woman) were placed in a comparison group which received two educational sessions over a period of 1 month. All subjects completed the Toronto Alexithymia Scale (TAS) before the start of group therapy, at the end of the 4-month period, and in follow-up assessment after 6-month, 1-year, and 2-year intervals. Results: In the psychotherapy treatment group, there was a significant reduction in the mean TAS score following group therapy, which was maintained over the 2-year follow-up period. In the educational group, there were no significant changes in mean TAS scores between the initial testing and any of the follow-up intervals. On an individual basis, a decrease to a lower level of TAS scores occurred in a higher percentage of patients in the treatment group than in the educational group. Over the 2-year follow-up period, patients with decreased alexithymia following group therapy experienced fewer cardiac events (reinfarction, sudden cardiac death, or rehospitalization for rhythm disorder or severe angina) than patients whose alexithymia remained unchanged. Conclusions: The results indicate that group psychotherapy is able to decrease alexithymia and that for many patients this change can be maintained for at least 2 years. A reduction in the degree of alexithymia seems to influence favorably the clinical course of CHD.