PURPOSE: Emerging data suggest that many patients are non responsive or only partially responsive to antiplatelet therapy. Different methods have been described to identify such patients. Traditionally light transmission aggregometry (LTA) is considered the gold standard. Helena Laboratories ICHOR/ Plateletworks® is a useful point of care test, based on platelet counts and provides a rapid assessment of platelet function. In this study we compared a rapid platelet function analysis system (ICHOR/ Plateletworks®) to light transmission aggregometry (LTA).
METHODS: Blood samples for the study were collected from 48 patients at the time of the cardiac catheterization. Samples were transferred to EDTA tubes, ADP 5 μmol, ADP 20 μmol, Arachidonic Acid (AA) pretreated tubes for the ICHOR/ Plateletworks® and on red tops for the LTA analysis. Samples for LTA measurement had to be centrifuged for 6 minutes with 1000 rpm to extract platelet rich plasma, and 10 minutes with 3000 rpm for the platelet poor plasma. After preparation AA 500, ADP 5 μmol, ADP 20 μmol were added as agonist on the LTA wells. Pearson correlations was used to analyze the relationship between the 3 pairs of variables. Paired sample t-test was used to assess the agreement between the results from both methods.
RESULTS: There was significant correlation between ICHOR and LTA for all three variables respectively p ≤; .001 (AA: R2 = 0.81, ADP 5μmol R2 =0 .60, and ADP 20 μmol R2 = 0.48. Paired sample t-tests were also significant and showed a strong relationship between both these methods for the same variables (AA t = 2.69, p = .01, ADP 5μmol t = 6.68, p < .001, ADP 20 μmol t = −3.02, p = .004).
CONCLUSION: The data obtained from ICHOR/ Plateletworks® revealed an excellent correlation with the gold standard LTA, offering a much easier, faster and friendlier method for the evaluation of the platelet function with similar results as obtained from the LTA.
CLINICAL IMPLICATIONS: ICHOR point of care testing can be used to asses platelet non-responders.
DISCLOSURE: Sotir Polena, No Financial Disclosure Information; No Product/Research Disclosure Information