Perioperative anticoagulation

Question 1

Describe the patients at HIGH thrombotic risk on anticoagulant therapy

Answer 1

MECHANICAL HEART VALVES

• Any mitral valve prostheses
• Mechanical aortic valve prosthesis
• Recent stroke/TIA < 6/12

ATRIAL FIBRILLATION

• CHA2DS2-VASc score 7 -9
• Recent stroke/TIA < 3/12
• Rheumatic valvular heart disease

VTE

• Recent < 3/12
• Severe thrombophilia (protein C/S def | Antithrombin | Antiphospholipid | multiple abN

Question 2

Describe the patients at MODERATE thrombotic risk on anticoagulant therapy

Answer 2

MECHANICAL HEART VALVE
- Bileaflet Aortic Valve Prosthesis + another RF: AF/HPT/Prior CVA/TIA/DM/CHF/Age>75 yrs

ATRIAL FIBRILLATION
- CHA2DS2-VASc score 4 - 6

VTE

• 3 - 12 months
• Nonsevere thrombophilia (factor V leiden)
• Recurrent VTE
• Active cancer

Question 3

Describe the patients at LOW thrombotic risk on anticoagulant therapy

Answer 3

MECHANICAL HEART VALVE
- Bileaflet Aortic Valve Prosthesis without other RF

AF
- CHA2DS2-VASc score 0 - 3

VTE
- > 12 months and no other RF

Question 4

Describe the timing of bridging for patients with high risk thrombosis

Answer 4

HIGH RISK THROMBOSIS
Preoperative and postoperative bridging
Stop Warfarin 5 days before: INR < 1.5 -2.0
Start LMWH day -3 prior to surgery
Stop LMWH after morning dose day -1
Surgery: day 0
Start LMWH and Warfarin day + 2 (low bleeding risk)
Start LMWH and Warfarin day +3 (high bleeding risk)
Stop LMWH when INR is therapeutic