Erythrocyte aggregation portends worse outcomes in unstable angina patients undergoing percutaneous coronary interventions

Objective: The positive correlation between the time from symptom onset to the appearance of an inflammatory response and erythrocyte aggregation (EA) in the peripheral blood of acute coronary syndromes (ACS) patients had been previously reported by us. We now analyze the added prognostic value of EA in ACS patients undergoing percutaneous coronary interventions (PCI). Methods: We performed an analysis on prospectively collected data at a tertiary hospital catheterization laboratory between 2006-2011. Cox regression models were fitted for EA cut-offs and performed separately for myocardial infarction (MI) and unstable angina pectoris (UAP) patients. Major adverse cardiovascular events (MACE) were defined as all-cause mortality, MI and stroke. Follow up time was defined as the time from PCI to either MACE or November 20, 2011. Results: Included were 1055 patients (637 with MI and 418 with UAP). The median follow up in the MI and the UAP groups was 14 and 15 months, respectively (maximal follow up of 4.1 years). In the UAP group there was a significant increase in the MACE for the group with high EA (HR = 2.3, p = 0.04) compared to the group of patients with low EA. This was not found for patients presenting with MI. Conclusions: Elevated EA portends worse outcomes in UAP patients undergoing PCI.