Mean platelet volume (MPV) and platelet count (PLT) were measured by a Coulter Counter Model S-Plus and cardiac output (CO) was measured with the dye dilution method. We reported previously MPV was significantly increased (p<0.01) and PLT was significantly decreased (p<0.001) in patients with congestive heart failure as compared to normal subjects. In this study, MPV, PLT and CO were measured before and after treatment of patients with cardiovascular disease including low output group (% Cardiac index<60%). After the symptoms were improved, MPV was significantly decreased (p<0.001), while PLT was significantly increased (p<0.01) in patients with congestive heart failure. MPV and PLT exhibited a significant negative correlation in patients with cardiovascular disease (r=-0, 439, p<0.01). In low output group, MPV was significantly decreased (p<0.01) after treatment. These results indicate that the measurement of MPV and PLT is useful in understanding the cardiac function and clinical course in patients with cardiovascular disease.
