Aging is often considered a risk factor for silent ischemic cardiopathy. Using endermic electric stimuli, we assessed the course of pain threshold and pain tolerance in 23 male subjects affected by silent myocardial ischaemia, and in 20 male subjects with symptomatic cardiopathy; we also attempted to define the role played by age. Values of pain threshold were assessed using the same method in a group of 40 healthy subjects, five for each age decade, between 10 and 90 years. Our data show a significant difference in pain threshold and tolerance between subjects with silent and symptomatic cardiopathies (34.7 +/- 12.6 mA versus 25.2 +/- 12.5 mA: P < 0.001 for the threshold and 68.5 +/- 21.2 mA versus 46.0 +/- 22.3: P < 0.001 for tolerance). The fact that the significance of our results is superior to that of other studies may be due to the particular method of stimulation used and to the uniformity of the sample studied (sex, age, exclusion of subjects with anxiety-depressive symptoms). No difference was found in pain threshold as regards age. It seems probable that the difference found between subjects with silent and symptomatic cardiopathies is due to the different modulation of the perception of pain at a central level, independently of the age factor.