Low CD4/CD8 T lymphocyte ratio in acute myocardial infarction.

T lymphocyte subsets were analysed using monoclonal antibodies and flow cytometry to determine whether myocardial infarction and cardiopulmonary resuscitation induce changes in these. Groups of 11 infarct patients and 10 patients with past cardiopulmonary resuscitation were compared with 11 age- and sex-matched controls and 12 sepsis patients. The differences in the CD4/CD8 ratios between the four groups were significant (F = 7.71, P = 0.001). The infarct patients had lower CD4/CD8 ratios (mean +/- s.d. 0.83 +/- 0.43) than the control (2.12 +/- 1.13; P = 0.001) or sepsis cases (1.76 +/- 1.05; P = 0.004), but their ratios did not differ from those of the resuscitation group (0.93 +/- 0.79, P = 0.84). The latter group also had lower ratios than the control (P = 0.003) and sepsis groups (P = 0.013). Most infarct patients had an on admission inverted CD4/CD8 ratio which usually returned to normal in the next 2 days. A permanently low CD4/CD8 ratio may be a poor sign prognostically after both myocardial infarction and resuscitation.