Pearls in anticoagulation

 

1. When and in whom should thrombophilia testing be done? Are the results going to change management? Why does the pt want the testing? Test at the appropriate time.

2. Middle of Stephan Moll's pyramid in whom testing is valuable- minor provoking factors--> travel, OCP ( recent start or change)

3. Estrogen and blood clotting

ASH strong recommendation : do not do blanket testing for thrombophilia just because they are about to start OCP. But if first degree family member with a VTE, recommend progestin based OCP.

Pregnancy planning: miscarriage, recurrent pregnancy loss ( other than APL) not improved with heparin for any other thrombophilia.

4. Do not test for thrombophilia during an acute clot or while inpatient.

5. Antiphospholipid inpatient testing: young patients with cryptogenic stroke. infection, pregnancy, malignancy can affect cardiolipin and beta2 microglobulin. Lupus anticoagulant is affected by all anticoagulants.

6. Valvular disease and anticoagulation: 

-oral anticoagulation : fresh bioprosthetic valve 5 % risk of clot over 3 months. 

- assess bleeding risk: CKD, NSAID

Rx oral VKA or DOAC 1-3 months. Followed by low dose ASA.

If high risk bleeding--antiplatelet rather than anticoagulant.

Historically aortic and mitral valve replacement risk was considered differently ( mitral higher risk). Antiplatelet only if high risk bleeding, otherwise even aortic bioprosthetic valve should get an anticoagulant.

RIVER Trial ( afib): In patients with atrial fibrillation and a bioprosthetic mitral valve, rivaroxaban was noninferior to warfarin

ENBALV trial edoxaban non afib population. Edoxaban was comparable to warfarin in preventing stroke or systemic embolism and intracardiac thrombus in patients with non-valvular atrial fibrillation (AFib) within three months after bioprosthetic valve surgery, 0.5% of patients receiving edoxaban experienced a stroke or systemic embolism compared with 1.5% of patients receiving warfarin. The incidence of major bleeding and clinically relevant bleeding was numerically higher in patients assigned to the edoxaban group compared with the warfarin group, however, no fatal bleeding or intracranial hemorrhage was observed with edoxaban. One fatal intracranial hemorrhage occurred in the warfarin group.

  Valvular versus non valvular: or rheumatic versus non rheumatic

In rheumatic valvular Afib-- use VKA not DOAC- Reference NEJM