This exploratory study examined the role of family interaction in structuring and maintaining high-risk behaviors in difficult-to-manage patients with heart disease and the use of time-limited, social systems-oriented therapy to modify such behaviors. The study was based on the assumption that "difficult to manage" patients with heart disease, ie, those who failed to modify their high-risk behavior patterns following a cardiac event--and their families, in their attempts to deal with the threat of heart attack, would interact with one another in a manner which would maintain, however unintentionally, the patient's high-risk behavior pattern. Nine such "difficult heart families" were referred to the project. In each case the patient's wife was seen individually for a maximum of five clinical interviews for the purpose of modifying her method of dealing with, and presumably maintaining, her husband's high-risk behaviors. Contact with the patient with heart disease was minimal and used for information-gathering only. In each case, when the wife made the prescribed changes in dealing with her husband, a desirable change in one or more of his high-risk behaviors followed.