Author Affiliations: Department of Cardiology, Careggi Hospital, Florence, Italy (email@example.com).
In Reply: The main objective of our study was to address the association of HRPR after 600-mg clopidogrel loading with long-term outcomes in patients with acute coronary syndromes receiving PCI and antithrombotic treatment adjusted according to the results of the ADP test by increasing the chronic dose of clopidogrel or ticlopidine. High residual platelet reactivity was significantly associated with increased risk of thrombotic events despite some effect of adjusted therapy on in vitro tests. The results of the study suggested that HRPR could be a nonmodifiable risk factor for thrombotic events because normalization of the ADP test was not associated with improved outcome; the primary end point event rates were identical (14.9%) in the subgroups of patients with a normalized or persistently abnormal ADP test after treatment adjustment. If these results are confirmed in further studies, repeat in vitro platelet function tests with the goal of tailoring therapy in high-risk patients will be unnecessary.
Valenti R, Parodi G, Antoniucci D. High Residual Platelet Reactivity and Thrombotic Events—Reply. JAMA. 2011;306(23):2561-2562. doi:10.1001/jama.2011.1839