1. Which patient is a good candidate for a novel oral anticoagulant (NOAC)?
a. Patients with Atrial Fibrillation with CHADS score at least 1, CHADS VASc at least 2
2. Which patients were NOT included in the clinical trials?
a. “Valvular” AF (mechanical prosthetic valve, mod or sev MS). Other valvular abnormalities were included (i.e. MR, AS, TR, bioprosthetic valves etc) and thus are appropriate for NOACS.
b. Creatinine clearance c. Stroke within 7-14 days
3. Which patients with atrial fibrillation should be treated with warfarin and not a NOAC?
a. Mechanical heart valves
b. Severe renal insufficiency (Creatinine clearance < 30ml/min)
c. Patients needing dual antiplatelet therapy d. Those who cannot afford a NOAC
4. How do I transition my patient from warfarin to a NOAC?
a. Stop warfarin b. Wait for INR to be approximately 2.0 or less and then start NOACs.
5. What labs need monitoring on NOACs?
a. Yearly: hemoglobin, renal and liver function
b. 6 month: renal function if CrCl 30-60 or if on dabigatran and >75 years or fragile
c. 3 months: if CrCl 15-30
6. How should follow up be scheduled?
a. New start in ED: follow up appointment in 1 week, then one month then three months with provider
b. Start in clinic: One month for visit then 3 months to assure adherence, answer questions
7. Is it possible to use the Duke Coagulation Clinic to help with initiating and monitoring patients on NOACs?
a. Yes, for patients who are already established with a provider in the Duke Health System. Service will include education, adherence, review of medications for interactions, and a follow-up visit in one additional month
b. Duke Anticoagulation clinic phone number:
8. How can I measure or improve adherence to a NOAC?
i. Do you have trouble taking your medication?
ii. What are the benefits of taking this medicine?
iii. Do you have trouble remembering to take your medication?
iv. Can you afford this medicine?
b. Engage family members who help assure adherence
c. Encourage use of pill organizers (not dabigatran because it needs to stay in the bottle)
d. If you can, check to see if refills are occurring that are necessary to assure supply needed
e. Ask patients to bring in their remaining medication
f. Re-educate on importance of strict adherence
g. Consider checking PT to see if elevated which would suggest use of novel agents
9. Can I measure the effect of a NOAC?
10. What do I do if my patient is scheduled for a procedure?
a. Determine the risk of the procedure
i. Low Risk of bleeding (ie pulling one tooth, cataract surgery): Stop for 2-3 half-lives (1-2 days)
ii. Moderate Risk: 4-5 half-lives (2-3 days)
iii. High risk: at least 5 half-lives (longer with dabigatran and CrCl <50) and check coagulation markers prior to procedure (aPTT for dabigatran and PT for rivaroxaban)
b. Resume after allowing hemostasis, usually the next morning. Remember that unlike warfarin, the effect is almost immediate and thus resuming too early can result in bleeding.
i. Decisions need to be made based on risk of bleeding and risk of stroke. Here are some examples of what might be reasonable for a typical patient.
1. If a patient is having a tooth pulled (low risk) and is on dabigatran with normal renal function, take the morning dose, skip the next two doses (evening and next morning), and have the tooth pulled that day, and restart the next morning.
2. If a patient on apixaban is having colonoscopy that might involve polypectomy (medium risk since not visible), take the evening dose and skip the next 3 doses, have colonoscopy, and resume that night if no polypectomy and next morning if polypectomy.
3. If a patient is having neurosurgery and is on rivaroxaban, take in the evening, skip next two evening doses, and have surgery next day only after checking to be sure PT is normal the next morning. Resume the next day or two or more days later depending on bleeding risk.
c. For procedure specific recommendations, please refer to procedures tab off the home page.
11. What do I do if a patient is bleeding and has been taking a NOAC?
i. Local measures
ii. Activated charcoal if taken within 2-4 hours
iii. Hemodialysis, at least for dabigatran, especially if with renal failure
iv. Replace blood products according to hgb, coagulation markers
v. Consider platelet transfusion if on antiplatelet drugs for severe bleeding
vi. For life threatening bleeding, obtain a hematology consult. With the consult, consider PCC (KCentra = 4-factor PCC) or activated factor VII.
vii. Time is on your side
12. How can I prevent bleeding in my high risk patients?
i. Avoid aspirin for most patients, except those with recent ACS (within one year)
ii. Avoid NSAIDs
iii. Consider PPI especially if history of upper GI bleeding
iv. Consider lower dosing of drug, if in “grey zone” for which dose to use
v. Apixaban has strongest evidence of lower bleeding risk versus warfarin
13. What if my patient has a stroke or an MI while taking a NOAC? What do I do?
i. For acute stroke, ICH risk may be increased (as it appears to be on warfarin). Some advocate to consider lytics if PTT is normal on dabigatran, INR normal on rivaroxaban, and/or if at least 24 hours since last dose of any of the three given 12 hour half-life.
14. How do I adjust doses for my patient with renal insufficiency?
i. Avoid all NOACS if creatinine clearance < 30
ii. Dabigatran: use 110 mg dose if creatinine clearance < about 40; in US, use another drug if <40, or use the 75 mg dose but no outcome trials to guide
iii. Rivaroxaban: use 15 mg dose if ClCr < 50
iv. Apixaban: use 2.5 mg dose if at least 2 of 3: creat ≥1.5, age ≥80, weight ≤ 60.
v. Warfarin if < 25 to 30, but benefit has not been shown to clearly outweigh risk in this group even with warfarin.
15. If my patient is taking aspirin and I start a NOAC, should I tell them to stop taking aspirin?
i. Use aspirin for recent ACS, recent CABG (one year)
ii. Avoid aspirin for most other patients
16. Is GI bleeding more likely on NOACS than warfarin?
a. Yes, at least for dabigatran and for rivaroxaban. GI bleeding with apixaban is similar or slightly lower than warfarin. GI bleeding location shifts with the NOACs to be more likely lower than it is with warfarin
17. If a patient is on aspirin and clopidogrel (or another P2Y12 antagonist), is it OK to use a novel drug?
a. For a patient on aspirin and clopidogrel, adding any oral anticoagulant (warfarin or any of the new drugs) increases bleeding substantially, around 4-fold in many studies. Since we have more experience with warfarin, until more data are available, most recommend warfarin (with target INR 2-2.5), low dose aspirin, and clopidogrel, for patients who need OAC and dual antiplatelet therapy. PPI is advisable as well in these patients, and use the “triple therapy” for the shortest necessary time.