Erythrocyte aggregation kinetics for studying the vascular phase of inflammation in patients with suspected acute coronary syndrome or acute stroke.

Inflammation plays a complex role in the pathophysiology of both acute coronary syndrome (ACS) and acute stroke (AS). Erythrocyte aggregation is a physiological phenomenon. Its initial kinetics (EAK), measured at the point of care in 20s, is a powerful marker of inflammation accelerated early in the inflammation process. Inflammation is highly suspected when EAK during the first 5 s (EAK5s) has a half-life less than 1.86s. EAK5s is the first marker of the vascular phase of inflammation, activated when systemic infection is present. We conducted two clinical studies in patients in whom either ACS (n = 34) or AS (n = 247) was suspected. We show that EAK is accelerated in many, but not all the patients: EAK5s variation coefficients ranged 6.9-37% across disease groups. EAK5s failed to identify ACS and AS patients among those in whom either condition was suspected. However, EAK5s may identify disease phenotypes such as no-ST elevation myocardial infarction (NSTEMI) or epilepsy in which the vascular phase of inflammation is activated: ROC areas under the curve 0.81 (95% CI 0.66-0.96) and 0.68 (95% CI 0.55-0.82) respectively. Besides other mechanisms, EAK, now easily measured, can be used to better understand the complex role of inflammation and its vascular phase in cardiovascular diseases.