Factor Impacting Reliability Number of Tests (%)
Tests taken in patients loaded with clopidogrel or at steady-state 53 (56%)
Tests taken when clopidogrel was being held to assess for surgery or reason for bleeding 27 (28%)
Tests taken in patients not at steady-state 9 (9%)
Tests taken when platelet function had not recovered from interfering agentsa 6 (6%)
Tests taken in thrombocytopenic patientsb 1 (1%)
Tests taken in patients with inherited platelet disorders 0 (0%)
Tests taken appropriately 80 (84%)
a. Abciximab within the past 14 days, eptifibitide or tirofiban within the past 48 hours, or cilostazol within the past 12 hours before testing
b. Patient’s platelet function had also not recovered from an interfering agent
Table 2: Factors Impacting P2Y12 Testing Reliability.