Abstract
We measured the values of hemorheological parameters of blood viscosity, plasma viscosity, hematocrit, serum protein, albumin and plasma fibrinogen in 12 patients with acute cerebral infarction (mean age : 69.1 Y.O.) within 3 days and at 1 month after onset, respectively, 30 patients with chronic cerebral infarction (mean age : 66.2 Y.O.) at 12.5 months (mean) after onset, 14 patients with hypertension (mean age : 63.4 Y.O.), 12 patients with hyperlipemia (mean age : 62.9 Y.O.), and 15 elderly controls (mean age : 65.8 Y.O.), respectively. The corrected blood viscosity at the hematocrit level of 45%, yield shear stress index, and fibrinogen/albumin ratio were calculated at the same time.
The values of corrected blood viscosity, plasma fibrinogen level, yield shear stress index and fibrinogen/ albumin ratio in patients with acute cerebral infarction within 3 days after onset were significantly higher while those of serum albumin were lower as compared to those in elderly controls (p<0.00050.05). These differences persisted to be significant until 1 month after onset. The significant differences of the values of hemorheological parameters were observed as well in patients with chronic cerebral infarction (12.5 months after onset) as compared with those in elderly controls (p<0.00010.05). In patients with hypertension, the values of hematocrit, corrected blood viscosity, and yield shear stress index were significantly higher than in elderly controls (p<0.0050.05). In patients with hyperlipemia, the values of plasma viscosity, corrected blood viscosity, and yield shear stress index were higher than those in elderly controls (p<0.010.05).
Blood viscosity already increased in patients with hypertension and hyperlipemia higher than in elderly controls. After onset of cerebral infarction, blood viscosity increased further due to elevated plasma fibrinogen levels and subsequent increases of yield shear stress index, which might cause a persistent vicious cycle of cerebral circulation until the chronic stage of cerebral infarction.
