Abstract 12086: Platelet Function Tests Predict a Relationship Between On-Treatment Platelet Reactivity and Clinical Outcome in Patients Undergoing Percutaneous Coronary Intervention
Background: Trials comparing high on treatment platelet reactivity [HPR] and normal on treatment platelet reactivity [NPR] indicate association between HPR and adverse outcomes during percutaneous coronary intervention [PCI]. However, there is no consensus regarding the most appropriate method to quantify the on-treatment platelet reactivity [PR]. We conducted a meta-analysis comparing patients with HPR versus NPR to evaluate the ability of various tests measuring PR in predicting clinical outcomes in patients undergoing PCI.
Methods: We identified 24 prospective studies including 11067 patients. PR was measured at least 12 hours after clopidogrel loading by light transmission aggregometry [LTA] [16 trials], verify now P2Y12 assay [5 trials] and Vasodilator stimulated phosphoprotein phosphorylation [VASP] [3 trials]. End points included major adverse cardiovascular events [MACE], death, myocardial infarction (MI), stent thrombosis [ST], target vessel revascularization [TVR], non-TVR, and rehospitalization rates. Relative risks [RR] and 95% confidence intervals [CI] were determined. Test parameters for these assays were calculated using 2x2 table.
Results: HPR was associated with significantly higher risk of MACE [RR:2.61 CI:2.29-2.96, p<0.001], death [RR:2.63 CI:1.85-3.73, p<0.001], MI [RR:1.78 CI:1.45-2.19, p<0.001], and ST [RR:3.42 CI:2.44-4.80, p<0.001]. However, TVR [RR:0.94 CI:0.80-1.10, p=0.48], non-TVR [RR:1.62 CI:0.30-8.77, p=0.57], and rehospitalization rates [RR:1.53 CI:0.29-7.90, p=0.60], did not differ between groups [Figure 1]. Negative predictive value for all 3 assays for all outcomes studied was 93-100% but these tests have low sensitivity [30-50%], specificity [64-75%] and negligible positive predictive values [3-9%].
Conclusion: HPR was associated with significantly higher risk of cardiovascular events and studied assays have good negative predictive value for these events.
- © 2011 by American Heart Association, Inc.