Erythrocyte aggregation determined with the Myrenne aggregometer at two modes (M 0,M 1 ) and at two times (5 and 10 sec)

Erythrocyte aggregation index determined with the Myrenne aggregometer gives a wide range of values both in healthy and disease, as observed in the literature, making results less comparable. This is due to the fact that it gives two aggregation indexes depending on the rotation speed of the cone, M₀ (at stasis) and M₁ (at 3 s⁻¹) and time elapsed (5 or 10 sec), after the cone is stopped abruptly. We determined in 112 healthy volunteers both indexes at two modes and at two times, along with fibrinogen, plasmatic lipids and hematimetric indexes. The correlations between both the 5 and 10 sec mode, and the different variables were analysed and although a statistically significant correlation was observed in both modes, M₁ at 5 sec gave the highest correlation values: 0.445, 0.485, 0.364, 0.460 for T‐Chol, LDL‐Chol, Apo B/A₁ and fibrinogen, respectively; p<0.01. Therefore, we suggest that all the erythrocyte aggregation measurements should be performed at a hematocrit adjusted to 45%, with autologous plasma, and that an aggregation time of 5 sec (as opposed to 10 sec) should be used in order to avoid confusion and misunderstanding and to allow for comparability of results with the de Myrenne aggregometer between laboratories.