Abstract
The relationship between the rate of platelet MDA production in the early phase of MCLS and the incidence of coronary vascular complications of MCLS was investigated retrospectively. Most MCLS patients who showed increased or decreased values of platelet MDA production stimulated with arachidonic acid before aspirin therapy were later found to have cardiac complications as late sequelae of this disease, but no patients with normal production of platelet MDA suffered from such complications. This fact suggests that the measurement of platelet MDA production in the early phase before administration of aspirin could be one marker to predict the occurrence of coronary complications. The ability of the patients' plasma to regenerate PGI2 like activity in exhausted umbilical arteries fell within the normal range. This ability was, however, apparently reduced after the start of aspirin therapy. Electronmicroscopic studies on the circulating platelet cohort revealed that the platelets of patients with MCLS in the early phase demonstrated such abnormal changes as degranulation and vacuolization of platelets, supporting the biochemical changes of platelet function.
