title: Optimal thromboprophylaxis following bioprosthetic aortic valve replacement: still a matter of debate?
abstract: Optimal thromboprophylaxis following bioprosthetic aortic valve replacement (AVR) remains controversial. The main objective, which is the effective prevention of central nervous or peripheral embolic events, especially in the early postoperative period, will have to be weighed against the haemorrhagic risk that is associated with the utilization of different antithrombotic regimes. Most governing bodies in cardiovascular medicine have issued recommendations on thromboprophylaxis after the surgical implantation of aortic bioprostheses. However, the level of evidence to support these recommendations remains low, largely due to the inherent limitations of conducting appropriately randomized and adequately powered clinical research in this area. It is apparent from the recent surveys and large registries that there is a great variability in antithrombotic practice at an institutional or individual-clinician level reflecting this controversy and the lack of robust evidence. While organizational, financial or conceptual limitations could hinder the conduct and availability of conclusive research on optimal thromboprophylaxis after aortic bioprosthesis, it is imperative that all evidence is presented in a systematic way in order to assist the decision-making for the modern clinician. In this review, we provide an outline of the current recommendations for thromboprophylaxis, followed by a comprehensive and analytical presentation of all comparative studies examining anticoagulation vs. antiplatelet therapy after bioprosthetic AVR.
authors.affiliation: Department of Cardiac Surgery,  St Thomas' Hospital, London,  UK.
authors.forename: Muhammad I
authors.initials: MI
authors.lastname: Mydin
authors.forename: Georgios
authors.initials: G
authors.lastname: Dimitrakakis
authors.forename: Jenan
authors.initials: J
authors.lastname: Younis
authors.forename: Justin
authors.initials: J
authors.lastname: Nowell
authors.forename: Thanos
authors.initials: T
authors.lastname: Athanasiou
authors.forename: Antonios
authors.initials: A
authors.lastname: Kourliouros
mesh_terms: D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D001021:Aortic Valve / Q000601:surgery*; D001241:Aspirin / Q000008:administration & dosage; D001705:Bioprosthesis; D019317:Evidence-Based Medicine; D005343:Fibrinolytic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D017410:Practice Guidelines as Topic; D011474:Prosthesis Design; D018570:Risk Assessment; D012307:Risk Factors; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D014859:Warfarin / Q000008:administration & dosage
chemical_list: D000925:Anticoagulants; D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D001241:Aspirin