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Thromboembolism

Risk of thrombosis or thromboembolism

Initial indication for anticoagulation Patients at relatively LOW risk of thrombosis Patients at relatively HIGH risk of thrombosis
  Use Low Risk Protocol for patients in this column Use High Risk Protocol for patients in this column
Stroke prophylaxis due to Atrial Fibrillation  NO stroke/TIA in past month Stroke/TIA in the past month
DVT/PE Index event (eg DVT/PE) requiring anticoagulation occurred > 3 months ago Acute thrombosis (DVT) in past 3 months (consider caval filter if VTE within previous 2 weeks)

Mechanical heart valve See table below		 Lower risk valves-discuss management with cardiologist, some individuals need to be managed as HIGH risk. Higher risk valves - manage as HIGH risk
Risk of thrombosis with mechanical heart valves
 

Lower risk mechanical valves Higher risk mechanical valves

Lone Mechanical Aortic valve - Modern type (post-1990 in most cases)
Lone Mechanical Mitral valve - Modern type bileaflet or tilting valve and no previous embolic event		 ≥ 2 mechanical valves- e.g aortic and mitral OR mitral and tricuspid.
Any older style mechanical valve in mitral, aortic or tricuspid position inserted pre-1990.
PLUS all of the following:
  • Normal left ventricular function
  • No previous embolic event
  • Sinus Rhythm
 Modern lone mechanical valve PLUS any of the following:
  • Impaired left ventricular function
  • Previous embolic event (esp < 3mths) relating to valve
  • Pro-embolic arrhythmia (eg atrial fibrillation)