Anticoagulation

Question 1

DVT/PE with reversible or time-limited risk factor

Answer 1

INR: 2.5 (2-3)

• Start warfarin on day 1 and continue parenteral anticoagulation (preferred is fondaparinux but can do LMWH or UFH) for at least 5 days and until INR >=2 for at least 24 h
• If using LMWH, do once-daily dosing

Question 2

First unprovoked PE or proximal DVT

Answer 2

INR: 2.5 (2-3)
If proximal DVT/PE and low-mod risk: extend duration
If proximal DVT/PE and high risk: 3 mths
If unprovoked isolated distal DVT: 3 mths
For recurrences of unprovoked VTE:
- low-mod risk: extend therapy
- high risk: 3 mths
DVT with cancer: extended therapy with LMWH (preferred) or warfarin

Question 3

Anterior MI & LV thrombus or high risk of LV thrombus (EF<40%, anteroapical wall motion abnormality) and no stent

Answer 3

First 3 months: warfarin + aspirin (75-100mg/d)
Switch to dual antiplatelets for up to 12 mths
Then single antiplatelet

Question 4

Anterior MI & LV thrombus or high risk of LV thrombus and BMS

Answer 4

Triple therapy for 1 mth (wafarin, aspirin, clopidogrel)
Next 2 months warfarin and single antiplatelet
For upto 12 mths, dual antiplatelets
Then single antiplatelet

Question 5

Anterior MI & LV thrombus or high risk of LV thrombus and DES

Answer 5

Triple therapy for 3-6 mths
Dual antiplatelets for up to 12 mths
Then single antiplatelet

Question 6

A.fib and low stroke risk

Answer 6

No therapy (or just aspirin 75-325mg/d)

Question 7

A.fib and int-high risk

Answer 7

Dabigatran recommended
If stable CHD (no ACS in past year) or mitral stenosis: warfarin alone
If pt doesn’t want anticoagulant: ASA/clopidogrel

Question 8

A.fib with low-int risk and stent placement

Answer 8

Dual antiplatelet (ASA/clopidogrel) x 12 mth
Then warfarin long term

Question 9

A.fib with high risk and stent placement

Answer 9

Triple therapy x 1 mth (if BMS)
Triple therapy x 3-6 mth (if DES)
Then warfarin + single antiplatelet for long-term

Question 10

A.fib, low risk, acute ACS, no stent

Answer 10

Dual antiplatelet x 12 mths

Then warfarin alone

Question 11

A.fib with low-int risk and stent placement

Answer 11

Dual antiplatelet (ASA/clopidogrel) x 12 mth
Then warfarin long term

Question 12

A.fib with high risk and stent placement

Answer 12

Triple therapy x 1 mth (if BMS)
Triple therapy x 3-6 mth (if DES)
Then warfarin + single antiplatelet for long-term

Question 13

A.fib, low risk, acute ACS, no stent

Answer 13

Dual

Question 14

Rheumatic mitral valve dx in sinus rhythm and LA diameter >55cm

Answer 14

Warfarin for long-term

Question 15

Elective direct current cardioversion of a.fib >=48h or unknown duration

Answer 15

LMWH (tx dose) or UFH at presentation
After can use dabigatran or LMWH (tx dose)
Don’t have to prolong duration (>=7 wks) if a.fib <48h and is cardioverted

Question 16

Rheumatic mitral valve disease with hx of systemic embolism, LA thrombus or a.fib

Answer 16

Warfarin for long-term

Question 17

Rheumatic mitral valve dx in sinus rhythm and LA diameter >55cm

Answer 17

Warfarin for long-term

Question 18

Mitral bioprosthetic heart valve

Answer 18

If sinus rhythm, do warfarin for 3 mths then ASA (50-100mg/d)
If aortic bioprosthetic valve and NSR then ASA
For bioprosthetic valves with risk factors then long-term warfarin

Question 19

Mitral mechanical prosthetic valve

Answer 19

INR: 3 (2.5-3.5)

Add ASA if low bleed risk