title: Formation of platelet microaggregates correlates with adverse clinical outcome in patients with coronary artery disease.
abstract: Platelet activation plays a pivotal role in the pathogenesis of acute coronary syndromes. Laser-light scattering in a platelet aggregometer was used to evaluate aggregate size and number quantitatively. Small platelet aggregates ultimately develop into medium and then large platelet aggregates. Thus the measurement of small platelet aggregates is important in the evaluation of thrombus formation. We examined the relationship between small platelet aggregates and the occurrence of subsequent cardiovascular events. We followed-up 204 patients (149 men and 55 women, mean age 68 +/- 9 years) with coronary artery disease (CAD) for 48 months. Blood sampling to determine platelet aggregation was performed on the day of hospital discharge. The degree of small platelet aggregates [relative risk 4.34, 95% confidence interval (1.62-11.7), p = 0.004] and low left-ventricular ejection fraction [relative risk 2.88, 95% confidence interval (1.23-6.73), p = 0.015] were independent predictors of the occurrence of cardiovascular events in multivariate Cox hazard analysis. In Kaplan-Meier analysis, the degree of small platelet aggregates correlated with the probability of cardiovascular event occurrence. In patients with CAD, an increase in small platelet aggregates is closely correlated with the future occurrence of cardiovascular events
authors.affiliation: Department of Cardiovascular Medicine, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto City 860-8556, Japan.
authors.forename: Shinzo
authors.initials: S
authors.lastname: Miyamoto
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kawano
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Soejima
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kajiwara
authors.forename: Hideki
authors.initials: H
authors.lastname: Shimomura
authors.forename: Sunao
authors.initials: S
authors.lastname: Kojima
authors.forename: Jun
authors.initials: J
authors.lastname: Hokamaki
authors.forename: Seigo
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Hirai
authors.forename: Michihiro
authors.initials: M
authors.lastname: Yoshimura
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ozaki
authors.forename: Hisao
authors.initials: H
authors.lastname: Ogawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000473:pathology*; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008027:Light; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation; D016016:Proportional Hazards Models; D012307:Risk Factors; D012542:Scattering, Radiation; D013997:Time Factors; D016896:Treatment Outcome