title: In-stent thrombosis when switching ticagrelor to clopidogrel after percutaneous coronary intervention.
abstract: Dual antiplatelet therapy with aspirin and a P2Y12 receptor blocker has been proven to reduce subsequent cardiovascular events and in-stent thrombosis in patients undergoing percutaneous coronary intervention. Newer P2Y12 antagonists with faster onset and greater inhibition of platelet activity have improved cardiovascular outcomes but have created uncertainty with the appropriate dosing when switching between agents. Currently, there are no evidence-based guidelines to aid clinicians when switching between P2Y12 receptor blockers. Here we describe two patients that developed in-stent thrombosis when switching from ticagrelor to clopidogrel using a 300 mg clopidogrel loading dose. Both patients presented with ST elevation myocardial infarction and underwent stent placement but then developed in-stent thrombosis 48 hours after switching from ticagrelor to clopidogrel. These cases illustrate the severe consequences of suboptimal platelet inhibition and the need for prospective trials thoroughly powered to assess clinical outcomes in order to determine the most appropriate strategy when switching from ticagrelor to clopidogrel.
authors: a Division of Cardiology, Jackson Memorial Hospital , University of Miami Miller School of Medicine , Miami , FL , USA.
authors: Aaron E
authors: AE
authors: Brice
authors: a Division of Cardiology, Jackson Memorial Hospital , University of Miami Miller School of Medicine , Miami , FL , USA.
authors: Gabriel A
authors: GA
authors: Hernandez
authors: a Division of Cardiology, Jackson Memorial Hospital , University of Miami Miller School of Medicine , Miami , FL , USA.
authors: Mariluz
authors: M
authors: Sanchez
authors: a Division of Cardiology, Jackson Memorial Hospital , University of Miami Miller School of Medicine , Miami , FL , USA.
authors: Marshall
authors: M
authors: Haynick
authors: a Division of Cardiology, Jackson Memorial Hospital , University of Miami Miller School of Medicine , Miami , FL , USA.
authors: Cesar E
authors: CE
authors: Mendoza
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D000077144:Clopidogrel; D004334:Drug Administration Schedule; D054796:Drug Dosage Calculations; D057915:Drug Substitution / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D015539:Platelet Activation / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D017410:Practice Guidelines as Topic; D058921:Purinergic P2Y Receptor Antagonists / Q000627:therapeutic use*; D000072657:ST Elevation Myocardial Infarction / Q000097:blood / Q000503:physiopathology / Q000601:surgery; D015607:Stents; D013927:Thrombosis / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D000077486:Ticagrelor; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D058921:Purinergic P2Y Receptor Antagonists; D000077144:Clopidogrel; D000077486:Ticagrelor; D000241:Adenosine; D013988:Ticlopidine
keywords: Clopidogrel; loading dose; percutaneous coronary intervention; stent thrombosis; switching; ticagrelor