NIRCO med‎ > ‎periop‎ > ‎assessment‎ > ‎01 cardiovascular‎ > ‎thrombotic risk‎ > ‎

mechanical heart valves

Epidemiology (1):
  • Prevalence: overall rates of thrombosis (with and without bridging therapy) are 1.2% among patients with mechanical heart valve.
  • Risk factors:
    • Low annual risk (<5% thromboembolism/y): bileaflet aortic-valve prosthesis without atrial fibrillation, prior stroke or thromboembolic event, or known intracardiac thrombus.
    • Moderate annual risk (5-10% thromboembolism/y): bileaflet aortic-valve prothesis with atrial fibrillation. The assessment of a patient's individual risk-benefit tradeoff for discontinuation of antithrombotic agents is particularly important in patients of this group.
    • High annual risk (>10% thromboembolism/y): any mitral-valve prosthesis, any caged-ball or tilting-disk aortic-valve prosthesis, multiple mechanical heart valves, or stroke, TIA, or cardioembolic event.
References:
  1. Current Concepts: Management of Antithrombotic Therapy in Patients Undergoing Invasive Procedures. NEJM. 2013;368(22):2113-2124: full text | pdf.