Adjusting Antithrombotic Therapy after Stent Implantation for Acute Myocardial Infarction in a Patient with Very Low Platelet

Abstract

A 76-year-old woman presented with non-ST-elevation myocardial infarction. Platelet count was 10×109/L. Bone marrow cytology and platelet antibody testing 9 months earlier suggested refractory immune thrombocytopenia (unresponsive to glucocorticoid and γ-globulin). The patient stabilized after treatments that included clopidogrel, statin, nitrate, and conventional anti-heart failure drugs, but heart failure persisted. Nine days later, angiography revealed 90% occlusion in the left anterior descending artery, and the patient received a zotarolimus-eluting stent. Upon discharge from the hospital, the patient started to receive clopidogrel, statin, β-blocker, and spironolactone. The patient remained free from the symptoms and reported no signs of bleeding for the next 8 months until she was readmitted for pneumonia and heart failure. Platelet count at this time was 2×109/L. Clopidogrel was discontinued. Ginkgo leaf tablets (an herbal medication with reported activity against platelet aggregation) were initiated. Subsequent follow-up visits were unremarkable, until 16 months after percutaneous coronary intervention, when platelet count decreased to 1×109/L. Ginkgo leaf tablet was discontinued. In summary, the evidence supporting the efficacy of clopidogrel at shorter than the recommended 12 months is anecdotal, but the need to adjustment dual antiplatelet therapy in patients with very low platelet count is solid.