Antithrombotic therapy after heart valve surgery, contemporary practice in the United Kingdom

Abstract

Objectives There is a lack of high-quality data informing the optimal antithrombotic drug strategy following bioprosthetic heart valve replacement or valve repair. Disparity in recommendations from international guidelines reflects this. This study aimed to document current patterns of antithrombotic prescribing after heart valve surgery in the UK.
Methods All UK consultant cardiac surgeons were e-mailed a custom-designed survey. The use of oral anticoagulant (OAC) and/or antiplatelet drugs following bioprosthetic aortic (AVR) or mitral valve replacement (MVR), or mitral valve repair (MVrep), for patients in sinus rhythm, without additional indications for antithrombotic medication, was assessed. Additionally, we evaluated anticoagulant choice following MVrep in patients with atrial fibrillation (AF).
Results We identified 260 UK consultant cardiac surgeons from 36 units, of whom 103 (40%) responded, with 33 units (92%) having at least one respondent. The greatest consensus was for patients undergoing bioprosthetic AVR, in which 76% of surgeons favour initial antiplatelet therapy and 53% prescribe lifelong treatment. Only 8% recommend initial OAC. After bioprosthetic MVR, 48% of surgeons use an initial OAC strategy (versus 42% antiplatelet), with 66% subsequently prescribing lifelong antiplatelet therapy. After MVrep, recommendations were lifelong antiplatelet agent alone (34%) or following 3 months OAC (20%), no antithrombotic agent (20%), or 3 months OAC (16%). After MVrep for patients with established AF, surgeons recommend warfarin (38%), a direct oral anticoagulant (37%) or have no preference between the two (25%).
Conclusions There is considerable variation in the use of antithrombotic drugs after heart valve surgery in the UK and a lack of high-quality evidence to guide practice, underscoring the need for randomized studies.

Keywords: Aortic valve, anticoagulants, mitral valve, platelet aggregation inhibitors, warfarin, consensus