Antiplatelet effects of aspirin and clopidogrel after left atrial appendage (LAA) occluder implantation. (15th January 2019)

• Record Type: Journal Article
• Authors: Dannenberg, Lisa; Mourikis, Philipp; Naguib, David; Zako, Saif; Helten, Carolin; M'Pembele, René; Trojovsky, Kajetan; Konsek, Daniel; Wolff, Georg; Brockmeyer, Maximilian; Schulze, Volker; Levkau, Bodo; Hohlfeld, Thomas; Zeus, Tobias; Kelm, Malte; Polzin, Amin
• Is Part Of: International journal of cardiology. Volume 275(2019)
• Page Start: 95
• Page End: 100
• Publication Date: 2019-01-15
• Subjects: DAPT dual antiplatelet therapy -- HTPR high on-treatment platelet reactivity -- LAA left atrial appendage -- LAAC left atrial appendage closure -- LTPR low on-treatment platelet reactivity -- MACCE major adverse cardiac and cerebrovascular events -- MI myocardial infarction -- OT occluder thrombosis -- PRI platelet reactivity index -- TAVI transcatheter aortic valve implantation -- TIA transient ischemic attack; Aggregation -- Aspirin -- Clopidogrel -- LAA-occluder -- Platelet activation -- Platelet inhibition; Cardiology -- Periodicals; Electronic journals; 616.12
• DOI: 10.1016/j.ijcard.2018.10.040
• Languages: English
• ISSNs: 0167-5273

Abstract

Abstract: Background: The optimal antithrombotic strategy after interventional left atrial appendage closure (LAAC) is controversial. Dual antiplatelet therapy with aspirin and clopidogrel is the most frequently used regiment. However, pharmacodynamic response to antiplatelet medication differs significantly between individuals. Therefore, we aimed to analyse pharmacodynamic response to aspirin and clopidogrel after LAAC. Methods: In this study, we included 129 patients undergoing interventional LAAC. Primary end point was pharmacodynamic response to antiplatelet medication. Platelet reactivity was measured by light transmittance aggregometry and vasodilator stimulated protein phosphorylation assay. Secondary endpoints were TIMI bleeding events and MACCE during hospital course and one-year follow-up. Results: Insufficient pharmacodynamic response (high on-treatment platelet reactivity — HTPR) to clopidogrel occurred in 67 patients (52%); HTPR to aspirin in 15 patients (12%); low on-treatment platelet reactivity — LTPR — to clopidogrel in 13 patients (10%). No occluder thrombosis or stroke occurred during one year follow-up. Pharmacodynamic response to antiplatelet medication was not associated with MACCE. However, the incidence of TIMI minor bleeding was increased in patients with LTPR to clopidogrel. Conclusions: Impaired clopidogrel antiplatelet effects were very frequent in patients after LAAC. No stroke or occluder thrombosis occurred. Patients with LTPR to clopidogrel showed more minor bleeding events. Therefore, this hypothesis generating pilot study raises the question if clopidogrel early after LAAC is needed. This question should be addressed in large scale trials. Highlights: Impaired clopidogrel effects were frequent after left atrial appendage closure. Minor bleeding events were more frequent in patients with low on-treatment reactivity to clopidogrel. No occluder thrombosis or stroke occurred in one-year follow-up.