Four cases of cardiac rhabdomyomas were seen at the University of Minnesota Hospitals in a two-year span (1971 through 1973). All cases were associated with tuberous sclerosis. Three of the patients developed cardiac failure and died during the neonatal period. The fourth was found to have a pansystolic murmur and cardiomegaly in the neonatal period and, at 4 months of age, developed cardiac failure that responded to medical therapy. Now, at the age of 2½ years, he shows physical and mental retardation, but remains free of heart failure, though cardiac drug therapy has been discontinued for more than a year.