Inverse relationship between platelet density and reactivity alterations at coronary angiography

Abstract

This work investigates relationships between platelet density and reactivity. 21 individuals subject to coronary angiography were studied. Peak platelet density was analyzed using a newly developed electronic device. The apparatus measures light transmission through test tubes containing density-separated platelets, thus allowing an estimation of the platelet distribution in the gradient. A flow cytometry technique was used for determining platelet reactivity after stimulating with ADP. Platelet counts, mean platelet volumes, peak platelet density and platelet reactivity were determined immediately before (day 1) and 24 h after cardiac catheterization (day 2). For all parameters changes during the day of angiography were compared with platelet density alterations. The subjects were divided into two groups according to density changes at angiography. Group 1 individuals showed density alterations (i.e. day 2 - day 1 value) ≥-8 × 10-5 kg/l. In contrast, group 2 subjects either displayed density changes