Data from the 5-year Oldenburg Longitudinal Study were used for investigating the causes of differences in psychological well-being in a national sample of 1000 cardiac patients. In a subsample of 400 married patients, for whom data from the spouse were available, exogenous influences, cognitive mediators, and two measures of psychological distress were linked up in models explaining/predicting the level of anxiety and depression. A major hypothesis was the salience of the illness-related cognitions of the patient as a determinant of long-term behavior and mood state. Early patient subjective health perceptions, the 'primary appraisal' of threat/harm/loss, were found to be the most important predictors of subsequent psychological well-being at the fourth wave of the study several years later. As an instrument for patient screening and psychosocial intervention, Type A's and other groups of subjects seemed to constitute high-risk patient groups.