Clinical records of 48 patients who died suddenly and unexpectedly following coronary care unit discharge were analyzed. Twenty-five had myocardial infarction as sole cause of death and 23 had other contributing entities. Patients with moderate to severe congestive heart failure had a higher total incidence of specific dysrhythmias in the coronary care unit compared to others. Large infarctions involving the anterior wall, especially in patients with moderate to severe heart failure in the coronary care unit, were negative prognostic factors. Serious dysrhythmias occurred with greater frequency in patients with moderate to severe congestive heart failure compared to others. Degree of congestive heart failure was not related to death among patients with atrioventricular block in the coronary care unit. Monitoring after the coronary care unit (Intermediate coronary care unit) may further reduce mortality.