Usefulness of combining necrosis and platelet markers in triaging patientspresenting with chest pain to the emergency department

Background: Myocardial injury and platelet activation play important roles in the pathogenesis of unstable coronary syndromes. We sought to determine whether the combined measurement of platelet and necrosis markers would imp rove risk stratification, and yield higher diagnostic utility in patients p resenting to the emergency department with chest pain. Methods and Results: Platelet and soluble P-selectin together with myoglobi n, creatine kinase, CK-MB fraction, and troponin I were measured from the a utologous samples in 122 consecutive patients. Statistical analysis reveale d strong Spearman correlation coefficients (0.141-0.412; p <0.001) between platelet expression of P-selectin and plasma levels of necrosis markers. Pl atelet P-selectin and necrosis markers were independent predictors (c-index >0.7) for acute myocardial infarction, while plasma P-selectin exhibited r andom distribution. Elevated soluble P-selectin and myoglobin were the most valuable in identifying patients with congestive heart failure. None of th e markers were useful for triaging chest pain patients with unstable angina . Analysis of incremental gains (Chi-squares) reveals that with respect to platelet P-selectin, myoglobin adds 50 % to AMI diagnostic value, and creat ine kinase yields an additional 20 % in triaging these patients. The diagno stic value of soluble P-selectin is substantially (72 %) increased by myogl obin measurements, and enhanced even further (44 %) by adding cardiac tropo nin I for identifying heart failure patients among the chest pain populatio n. Conclusion: Simultaneous determination of platelet and necrosis markers imp rove the early diagnosis of acute myocardial infarction and congestive hear t failure among patients with chest pain presenting into the Emergency Depa rtment. Well controlled clinical trials are needed to prove the advantage o f combining platelet and necrosis data over presently used techniques in em ergency medicine.