Point-of-care determination of baseline platelet function as a predictor of clinical outcomes in patients who present to the emergency department with chest pain.
BACKGROUND
Increased platelet reactivity can identify patients at high risk for thrombotic events, but its clinical use has been impractical due to technical limitations. The purpose of the present study is to determine if a point-of-care measurement of platelet function in patients presenting to an emergency room with chest pain can identify those at high risk of adverse cardiac events.


METHODS
Platelet function was measured using the Ultegra-RPFA in 201 patients presenting to the emergency department with the primary complaint of chest pain and either known coronary disease or at least one cardiac risk factor. The primary endpoint was any major adverse cardiac events (MACE) [cardiac death, myocardial infarction (MI), re-admission for coronary revascularization] 6 months post-enrollment.


RESULTS
Platelet function at baseline ranged from 44 to 315 platelet activation units (PAU) (mean 175+/-6). Seventy-six patients experienced MACE (37.8%) by 6 months post-enrollment. Mean PAU was significantly lower in the group experiencing MACE (166+/-9 vs. 181+/-9; p=0.026). By univariate analysis, admission PAU was a significant predictor of MACE at 6 months (p=0.028). However, when adjusted for age, gender, cardiac risk factors, and a history of coronary artery disease (CAD) using multivariate logistic regression analysis, PAU was no longer significantly predictive of MACE (p=0.268).


CONCLUSIONS
Point-of-care testing of platelet function deserves further study for risk assessment and individualized therapy in the future.
Selvaraj
Carrie Lynn
CL
Department of Internal Medicine, Wilford Hall Medical Center, Lackland, AFB, TX, USA. selvarc@ccf.org
Van De Graaff
Eric John
EJ
Campbell
Charles L
CL
Abels
Brad S
BS
Marshall
John P
JP
Steinhubl
Steven R
SR
D000368:Aged; D001792:Blood Platelets / Q000378:metabolism* / Q000502:physiology; D002637:Chest Pain / Q000097:blood* / Q000175:diagnosis; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010979:Platelet Function Tests; D019095:Point-of-Care Systems; D011237:Predictive Value of Tests; D016896:Treatment Outcome