Abnormal Haemostasis and Blood Viscosity in Malignant Hypertension

Summary

We have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha₂-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.

Key words

Hypertension - Intravascular coagulation - Blood viscosity

• References

• 1 Kincaid-Smith P. Participation of intravascular coagulation in the pathogenesis of glomerular and vascular lesions. Kidney Int 1975; 7: 242-253
• 2 Gavras H, Oliver N, Aitchison J, Begg C, Briggs JD, Brown JJ, Horton PW, Lee F, Lever AF, Prentice CR M, Robertson JI C. Abnormalities of coagulation and the development of malignant phase hypertension. Kidney Int 1975; 8: 252-261
• 3 Brozovic M. Acquired disorders of blood coagulation. In: Bloom A, Thomas DP. (eds) Haemostasis and Thrombosis. Churchill Livingstone; Edinburgh: 1981. pp 411-438
• 4 Gavras H, Brown WC B, Brown JJ, Lever AF, Linton AL, MacAdam RF, McNicol GP, Robertson JI, Wardrop C. Microangiopathic haemolytic anaemia and the development of the malignant phase of hypertension. Circ Res 1971; 27 Suppl (Suppl. 02) 127-142
• 5 Collen D. Natural inhibitors of haemostasis, with particular reference to fibrinolysis. In: Bloom A, Thomas DP. (eds) Haemostasis and Thrombosis. Churchill Livingstone; Edinburgh: 1981. pp 225-235
• 6 Lowe GD O, Forbes CD. Blood rheology and thrombosis. Clin Haematol 1981; 10: 343-367
• 7 Breckenridge RT, Ratnoff OD. Studies on the nature of the circulating anticoagulant directed against haemophilic factor: with notes on an assay for antihaemophilic factor. Blood 1962; 20: 137-149
• 8 Alkjaersig N, Fletcher AP, Sherry S. The mechanism of clot dissolution by plasmin. J Clin Invest 1959; 38: 1086-1095
• 9 Buchan PC. Evaluation and modification of whole blood filtration in the measurement of erythrocyte deformability in pregnancy and the newborn. Br J Haematol 1980; 45: 97-104
• 10 Teger-Nilsson AC, Friberger P, Gyzander E. Determination of a new rapid plasmin inhibitor in human blood by means of a plasmin specific tripeptide substrate. Scand J Clin Lab Invest 1977; 37: 403-409