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Aims: Oral anticoagulation is considered standard therapy for stroke prevention in atrial fibrillation (AF). Endocardial activation triggers expression of pro-thrombotic mediators including tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1), and contributes to thrombus formation in the left atrial appendage (LAA) of AF patients. Recently, pleiotropic effects of specific P2Y12 receptor antagonists were demonstrated; however, whether these drugs possess antithrombotic effects on LAA endocardial cells currently remains unknown., Methods and Results: LAA were obtained from 14 patients with known AF undergoing elective cardiac surgery including LAA removal at the University Hospital Zurich. LAA endocardial cells were isolated and pre-incubated with ticagrelor (10-7, 10-6, 10-5M) or clopidogrel active metabolite (CAM) (1.5 × 10-8, 1.5 × 10-7, 1.5 × 10-6 M) before stimulation with tumour necrosis factor-alpha (TNF-α) (10 ng/mL). Finally, TF and PAI-1 expression and activity were analysed. Ticagrelor, unlike CAM, concentration dependently decreased TNF-α-induced TF expression and TF activity in LAA endocardial cells. Further, ticagrelor, but not CAM reduced PAI-1 expression and enzyme activity in TNF-α-stimulated LAA endocardial cells. In contrast, TF pathway inhibitor (TFPI) remained unaffected by both dugs., Conclusion: Ticagrelor, but not CAM, reduces expression and activity of TF and PAI-1 in LAA endocardial cells isolated from patients with AF, indicating possible local antithrombotic effects. Such pleiotropic properties of ticagrelor may contribute to a reduction in thromboembolic complications in patients with AF., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.)

Moderate-to-severe tricuspid regurgitation (TR) affects ∼1.6 million patients in the USA, of whom only 8000 undergo tricuspid surgery annually; this results in an extremely large number of untreated patients with significant TR. Therefore, there is a large unmet clinical need for patients with severe TR who are not referred for conventional surgery, mainly due to expected high surgical risk. Percutaneous procedures are an attractive alternative to surgery for patients deemed to be high-risk surgical candidates. Whereas over the past few years, the development and clinical use of percutaneous approaches to the aortic valve and mitral valve have been widespread, few data are available about the feasibility and the efficacy of the percutaneous tricuspid valve treatment. This review will explore the available technologies, which are today under evaluation and the preliminary clinical results., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)