Separate weights for heart ventricle walls and interventricular septa were analyzed in 110 hearts with autopsy findings of ischemic heart disease (coronary atherosclerosis, recent or old myocardial infarcts) and with no other cardiac or systemic causes of cardiac enlargement. In hearts with coronary atherosclerosis alone (without old or recent myocardial infarcts) no weight increase was observed in the left ventricle when compared to 29 controls. Patients having infarcts associated with nonstenosing atherosclerosis (less than 50% of the luminal diameter narrowed) of the coronaries had normal heart weights as well. On the contrary, infarcts associated with stenosing coronary sclerosis (narrowing more than 50%) showed significant signs of left ventricular weight increase, which is interpreted as compensatory heart hypertrophy. The greatest degree of hypertrophy was observed in hearts with left ventricular aneurysms.