We determined estimated myocardial infarct size in elderly versus nonelderly patients from 2 large multi-center studies: I from the prethrombolytic era (Multicenter Investigation of the Limitation of Infarct Size [MILIS] study) and I from the thrombolytic era (Thrombolysis In Myocardial Infarction-4 [TIMI-4] study). In the MILIS study, enzymatically estimated myocardial infarct size was smaller in patients greater than or equal to65 years old versus patients <65 years old, whereas in the TIMI-4 study, there was no difference in infarct size between patients greater than or equal to65 years old and those <65 years old, suggesting that a worse outcome of myocardial infarction in the elderly is probably not related to larger infarct size.