title: Reversible clopidogrel resistance due to right ventricular myocardial infarction: risk factor of recurrent stent thrombosis?
abstract: A 63-year-old male Patient was admitted to the intensive care unit due to acute inferior myocardial infarction with right ventricular dysfunction. He received a loading dose of clopidogrel (600 mg) and aspirin (500 mg) and was immediately revascularized by reopening of the proximal right coronary artery (RCA) and implantation of a bare metal stent. After primary successful intervention the patient suffered from thoracic pain on day 5 of admission. The ECG indicated reinfarction. The proximal RCA was again re-opened by PTCA alone. The following day the patient suffered again from thoracic pain with ST-elevation in the inferior leads, this time complicated by additional total AV-blockade. The angiography showed another time a thrombotic occlusion of the initially implanted stent. He received another intervention with implantation of additional two bare-metal stents, an aortic counter-pulsation and a temporary two-chamber pace maker. Tirofiban was administered for 24 h and the IABP was withdrawn after 60 h. The patient was discharged on Aspirin 300 mg/d, Clopidogrel 150 mg/d and Enoxaparin 40 mg/d. Six weeks later the patient demonstrated an improved right ventricular function (TAPSE 18 mm), liver enzymes were normal, and inhibition of platelet aggregation by clopidogrel (150 mg/d) was sufficient. In conclusion this implies that the reversible "clopidogrel-resistance" might have been due to congestion and reduced metabolism due to right ventricular infarction.
authors.affiliation: Heart Center Dresden, University of Technology Dresden, Dresden, Germany. karim.ibrahim@web.de
authors.forename: K
authors.initials: K
authors.lastname: Ibrahim
authors.forename: N
authors.initials: N
authors.lastname: Hass
authors.forename: S
authors.initials: S
authors.lastname: Kolschmann
authors.forename: R H
authors.initials: RH
authors.lastname: Strasser
authors.forename: R C
authors.initials: RC
authors.lastname: Braun-Dullaeus
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D001241:Aspirin / Q000627:therapeutic use; D000077144:Clopidogrel; D023921:Coronary Stenosis / Q000628:therapy; D003328:Coronary Thrombosis / Q000209:etiology*; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D054855:Drug-Eluting Stents / Q000009:adverse effects; D004562:Electrocardiography; D017984:Enoxaparin / Q000627:therapeutic use; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000628:therapy*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D012008:Recurrence; D012307:Risk Factors; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D013997:Time Factors; D000077466:Tirofiban; D016896:Treatment Outcome; D014443:Tyrosine / Q000031:analogs & derivatives / Q000627:therapeutic use; D018497:Ventricular Dysfunction, Right / Q000150:complications / Q000209:etiology / Q000628:therapy*
chemical_list: D017984:Enoxaparin; D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D014443:Tyrosine; D000077144:Clopidogrel; D000077466:Tirofiban; D013988:Ticlopidine; D001241:Aspirin