A comparison of the data published in anatomy textbooks and anthropological tables does not reveal any change in basic heart dimensions during the period since the beginning of the 20th century to nowadays. However, normal values of many other parameters have changed up to 30% over the same period. These changes may be caused by the acceleration phenomenon or the extension of average lifespan. The progress of laboratory medicine methodology permitted the introduction of new biochemical tests in myocardial infarct diagnosis, such as myoglobin and troponins T and I measurement, as well as better understanding of cardiac metabolism. Parameters describing the direction and intensity of metabolic changes are substrate extraction and metabolic equilibrium. The expression describing metabolic equilibrium contains heart mass value. Therefore, as studying heart mass in vivo is not possible, it may be important to study it in vitro. The study was performed on a group of 107 formalin-fixed human hearts. The organs came from adults of both sexes: 30 women and 77 men, aged 18 to 90 years. None of the hearts carried signs of macroscopic developmental abnormalities or pathologic changes.