Whole blood viscosity measurement in acute myocardial infarction: feasability and significance

Thrombolytic agents and new antiplatelet drugs used in acute myocardial inf arction (AMI) could change whole blood viscosity. The aim of this pilot tri al is to compare blood viscosity at four shear rate levels among three grou ps of patients: AMI receiving thrombolysis with alteplase (n: 10), AMI elig ible for primary angioplasty with abciximab (n: 10), healthy volunteers (n: 10). Viscosity measurement was obtained in 30 minutes with a Couette hemov iscosimeter. At baseline, blood viscosity level was higher in patients with acute coronary syndromes than in healthy volunteers (72 +/- 32 mPa.s versu s 51 +/- 13 mPa.s, p < 0.05). After thrombolysis, viscosity was higher at 9 0 minutes than at third day, paradoxically with fibrinogen elevation (72 +/ - 32 mPa.s versus 58 +/- 27 mPa.s. p = 0.01). In primary angioplasty with a bciximab, viscosity decreased significantly (56 +/- 28 mPa.s versus 43 +/- 13 mPa.s, p = 0.01). The effects of ionic contrast agent and abciximab are discussed. In healthy volunteers group, 100 mg aspirin once a day during 7 days reduces blood viscosity at high shear stress. The small size of the st udy population restricts correlation analysis with major clinical adverse e vents. A larger trial is necessary to evaluate the predictive value of whol e blood viscosity in reocclusive and/or hemorrhagic events in those reperfu sion strategies but also in case of thrombolytic agent and abciximab combin ation.