Introduction
Stroke risk reduction in NVAF with NOACs
Trial name | Trial design | No. of patients | Outcomes (annual rate vs. comparator,a %/y) | |||
---|---|---|---|---|---|---|
Stroke/Systemic embolism | All-cause mortalityb
| Major bleedingb
| Intracranial hemorrhageb
| |||
PROBE designd
|
N = 18113 Dabigatran 150 mg bid: n = 6076 | Dabigatran 150 mg: RR 0.66 (95 % CI 0.53, 0.82; p < 0.001 for superiority) | Dabigatran 150 mg: RR 0.88 (95 % CI 0.77, 1.00; p = 0.051) | Major bleeding: Dabigatran 150 mg: RR 0.93 (95 % CI 0.81, 1.07; p = 0.31) | Dabigatran 150 mg: RR 0.40 (95 % CI 0.27, 0.60; p < 0.001) | |
Dabigatran 110 mg bid: n = 6015 | Dabigatran 110 mg: RR 0.91 (95 % CI 0.74, 1.11; p < 0.001 for noninferiority) | Dabigatran 110 mg: RR 0.91 (95 % CI 0.80, 1.03; p = 0.13) | Dabigatran 110 mg: RR 0.80 (95 % CI 0.69, 0.93; p = 0.003) | Dabigatran 110 mg: RR 0.31 (95 % CI 0.20, 0.47; p < 0.001) | ||
Warfarin (adjusted dose, target INR 2.0–3.0): n = 6022 | ||||||
ROCKET-AF (rivaroxaban) [25] | Randomized, double-blind, double-dummy, noninferiority trial |
N = 14264 Rivaroxaban 20 mg/d: n = 7131 | HR 0.85 (95 % CI 0.70, 1.02; p = 0.07) | Major and CRNM bleeding: HR 1.03 (95 % CI 0.96, 1.11; p = 0.44) | HR 0.67 (95 % CI 0.47, 0.93; p = 0.02) | |
Warfarin (adjusted dose, target INR 2.0–3.0): n = 7133 | HR 0.88 (95 % CI 0.75, 1.03; p < 0.001 for noninferiority; p = 0.12 for superiority)e
| Major bleeding: HR 1.04 (95 % CI 0.90, 1.20; p = 0.58) | ||||
ENGAGE AF-TIMI 48 (edoxaban) [26] | Randomized, double-blind, double-dummy, noninferiority trial |
N = 21105 Edoxaban 60 mg once daily: n = 7035 | Edoxaban 60 mg: HR 0.79 (97.5 % CI 0.63, 0.99; p < 0.001 for noninferiority; p = 0.08 for superiority)f
| Edoxaban 60 mg: HR, 0.92 (95 % CI. 0.83, 1.01; p = 0.08) | Major bleeding: Edoxaban 60 mg: HR 0.80 (95 % CI 0.71, 0.91; p < 0.001) | Edoxaban 60 mg: HR 0.47 (95 % CI 0.34, 0.63; p < 0.001) |
Edoxaban 30 mg once daily: n = 7034 | Edoxaban 30 mg: HR 1.07 (97.5 % CI 0.87, 1.31; p = 0.005 for noninferiority; p = 0.10 for superiority)f
| Edoxaban 30 mg: HR, 0.87 (95 % CI, 0.79, 0.96; p = 0.006) | Edoxaban 30 mg: HR 0.47 (95 % CI 0.41, 0.55; p < 0.001) | Edoxaban 30 mg: HR 0.30 (95 % CI 0.21, 0.43; p < 0.001) | ||
Warfarin (adjusted dose, target INR 2.0–3.0): n = 7036 | ||||||
ARISTOTLE (apixaban) [24] | Randomized, double-blind, double-dummy, noninferiority trial |
N = 18201 Apixaban 5 mg bid: n = 9120 | HR 0.79 (95 % CI 0.66, 0.95; p < 0.001 for noninferiority; p = 0.01 for superiority) | HR 0.89 (95 % CI 0.80, 0.998; p = 0.047) | Major bleeding: HR 0.69 (95 % CI 0.60, 0.80; p < 0.001) | HR, 0.42 (95 % CI, 0.30, 0.58; p < 0.001) |
Warfarin (adjusted dose, target INR 2.0–3.0): n = 9081 | ||||||
AVERROES (apixaban) [32] | Randomized, double-blind, double-dummy, superiority trialg
|
N = 5599 Apixaban 5 mg bid: n = 2808 | HR 0.45 (95 % CI 0.32, 0.62; p < 0.001) | HR 0.79 (95 % CI 0.62, 1.02; p = 0.07) | Major bleeding: HR 1.13 (95 % CI 0.74, 1.75; p = 0.57) | HR 0.85 (95 % CI 0.38, 1.90; p = 0.69) |
Aspirin 81–324 mg/d: n = 279 |
Guidelines and quality measures for stroke risk reduction in AF
2012 AHA/ASA: Scientific Advisory [8] | 2012 ACCP [11] | 2012 ESC [7] | 2014 AAN [9]a
| 2014 ACC/AHA/HRS [10] | |
---|---|---|---|---|---|
Stroke risk | Guideline recommendations by stroke risk | ||||
Low | CHADS2 = 0 | CHADS2 = 0 | CHA2DS2-VASc = 0 | Clinicians might not offer anticoagulation to patients with NVAF who lack additional risk factors | CHA2DS2-VASc = 0 |
Aspirin, based on patient preference, estimated bleeding risk if anticoagulated, and access to high-quality anticoagulation monitoring | No therapy suggested rather than antithrombotic therapy | No antithrombotic therapy recommended | Clinicians might offer antithrombotic therapy with aspirin or no therapy at all | Reasonable to omit antithrombotic therapy | |
If antithrombotic therapy chosen, aspirin (75–325 mg/d) suggested rather than OAC or aspirin plus clopidogrelb
| |||||
Moderate | CHADS2 = 1 | CHADS2 = 1 | CHA2DS2-VASc = 1 | Not discussed | CHA2DS2-VASc = 1 |
Aspirin, based on patient preference, estimated bleeding risk if anticoagulated, and access to high-quality anticoagulation monitoring or adjusted-dose warfarin in appropriate patients | OAC suggested rather than no therapy. OAC suggested rather than aspirin alone or aspirin plus clopidogrel.b If OAC unsuitable or not desired, aspirin plus clopidogrelb suggested rather than aspirin alone | OAC therapy with adjusted-dose VKA (INR 2.0–3.0); a direct thrombin inhibitor (dabigatran); an oral factor Xa inhibitor (e.g., rivaroxaban, apixaban) should be considered, based upon an assessment of the risk of bleeding complications and patient preferences. For female patients aged <65 years with lone AF (CHA2DS2-VASc = 1 due to sex), no antithrombotic therapy should be considered | No therapy or OAC or aspirin may be considered | ||
High | CHADS2≥2 | CHADS2≥2 | CHA2DS2-VASc ≥2 | CHA2DS2-VASc ≥2 | |
Adjusted-dose warfarin in appropriate patients (in patients unsuitable for warfarin, aspirin plus clopidogrelb offers more protection against stroke than aspirin but with an increased risk of major bleeding) | OAC suggested rather than no therapy, aspirin alone, or aspirin plus clopidogrel.b If OAC unsuitable or not desired, aspirin plus clopidogrelb suggested rather than aspirin alone | OAC therapy with adjusted-dose VKA (INR 2.0–3.0); a direct thrombin inhibitor (dabigatran); an oral factor Xa inhibitor (e.g., rivaroxaban, apixaban) recommended, unless contraindicated | Clinicians should routinely offer anticoagulation to patients with NVAF and a history of TIA or stroke | OAC recommended (warfarin, dabigatran, rivaroxaban, or apixaban) | |
Treatment options | Guideline recommendations by agent | ||||
Adjusted-dose VKA | See recommendations by CHADS2 score | Patients with AF and mitral stenosis | INR of 2.0–3.0 likely reduces frequency and severity of ischemic stroke vs lower INR levels | Patients with mechanical heart valve (target INR 2.0–3.0 or 2.5–3.5 based on type and location of prosthesis) | |
Patients with AF and stable CAD | Patients with NVAF and CHAD2DS2-VASc ≥2 with end-stage CKD (CrCl <15 mL/min) or on hemodialysis | ||||
Patients with AF and ACS not undergoing stent placement (in combination with single antiplatelet for first 1–12 mo, after which treat as for patients with AF and stable CAD) | |||||
Dabigatran | 150 mg bid is an efficacious alternative to warfarin in patients with NVAF who have ≥1 additional risk factor for stroke and CrCl >30 mL/min | Recommended over adjusted-dose VKA in cases where OAC recommended | Probably more effective than warfarin for reducing risk of stroke or SE | Recommended for patients unable to maintain a therapeutic INR level with warfarin | |
Reduce dosage to 75 mg bid in patients with moderate renal impairment (CrCl 15–30 mL/min)c
| Dabigatran 150 mg bid recommended for most patients | Hemorrhage risk was similar overall between dabigatran 150 mg and warfarin; ICH was less frequent with dabigatran 150 mg than warfarin; GI bleeding more frequent with dabigatran 150 mg than with warfarin | May be considered in patients with renal impairment: 150 mg bid in patients with mild renal impairment (CrCl >30 mL/min); 150 mg or 75 mg bid in patients with moderate renal impairment (CrCl >30 mL/min); 75 mg bid in patients with severe renal impairment (CrCl 15–30 mL/min) | ||
• Dabigatran 110 mg bid recommended for: | |||||
• Elderly patients (aged ≥80 y) | |||||
• Concomitant use of interacting drugs | |||||
• HAS-BLED ≥3 | |||||
• Moderate renal impairment (CrCl 30–49 mL/min) | |||||
Not recommended in patients with severe renal impairment (CrCl <15 mL/min) | Recommended over adjusted-dose VKA in cases where OAC recommended | Not recommended in patients with severe renal impairment (CrCl <30 mL/min) | Not recommended for patients with CrCl<15 mL/min | ||
Rivaroxaband
| 20 mg/d is a reasonable alternative to warfarin in patients with NVAF at moderate to high risk of stroke (prior history of TIA, stroke, or SE, or ≥2 additional risk factors) 15 mg/d may be considered in patients with renal impairment (CrCl 15–50 mL/min)c
| Recommended over adjusted-dose VKA in cases where OAC recommended | In patients with NVAF at high risk of cerebral or systemic embolism. Probably as effective as warfarin for prevention of cerebral and systemic embolism, with no difference in risk of major bleeding episodes except GI bleeding | Recommended for patients unable to maintain a therapeutic INR level with warfarin | |
May be considered in patients with renal impairment: 20 mg/d for patients with mild renal impairment (CrCl >50 mL/min); 15 mg/d for patients with moderate or severe renal impairment (CrCl 15–50 mL/min) | |||||
Rivaroxaban 20 mg/d recommended for most patients | |||||
Rivaroxaban 15 mg/d recommended for: | |||||
• HAS-BLED ≥3 | |||||
• Moderate renal impairment (CrCl 30–49 mL/min) | |||||
Should not be used in patients with severe renal impairment (CrCl <15 mL/min) | Not approved at time of guideline preparation | Not recommended in patients with severe renal impairment (CrCl <30 mL/min) | Associated with lesser frequency of ICH and fatal bleeding compared with warfarin | Not recommended for patients with CrCl < 15 mL/min | |
Apixabane
| As an alternative to warfarin or aspirin: 5 mg bid is relatively safe and efficacious in patients with NVAF who have ≥1 additional risk factor and ≤1 of the following additional criteria: age ≥80 y, weight ≤60 kg, or serum creatinine ≥1.5 mg/dL | Recommended over adjusted-dose VKA in cases where OAC recommended apixaban 5 mg bid | In patients with NVAF at moderate risk of embolism, 5 mg bid is likely more effective than warfarin | Recommended for patients unable to maintain a therapeutic INR level with warfarin | |
• 2.5 mg bid may be considered in patients with ≥2 of the additional criteria described abovec
| Apixaban 2.5 mg bid recommended for patients with renal impairment | Superiority is related to decreased risk of bleeding and reduced mortality, while its effect on reduction in risk of cerebral and systemic embolism is not superior to warfarin | 5.0 mg bid in patients with mild or moderate renal impairment or 2.5 mg bid in patients who meet dose reduction criteria (CrCl ≥1.5 mg/dL, ≥80 years of age, body weight ≤60 kg) | ||
Should not be used in patients with severe renal impairment (CrCl <25 mL/min) | Not approved at time of guideline preparation | Not recommended in patients with severe renal impairment (CrCl <30 mL/min) | Likely more effective than aspirin for decreasing risk of stroke or SE in patients with NVAF who have moderate risk of embolism and are not candidates for warfarin | No recommendation in patients with severe renal impairment or end-stage CKD | |
Edoxaban | Not approved at time of guideline preparation | Not approved at time of guideline preparation | Not approved at time of guideline preparation | Not approved at time of guideline preparation | Not approved at time of guideline preparation |
Other agents | Oral anticoagulation is likely more effective than clopidogrel plus aspirin, but ICH is more common | ||||
Triflusal plus acenocoumarol and moderate-intensity anticoagulation (INR 1.25–2.0) is likely more effective than treatment with acenocoumarol alone and conventional-intensity anticoagulation | |||||
Combination of low-dose aspirin and dose-adjusted VKA therapy probably increases risk of hemorrhage | |||||
Combination of clopidogrel and aspirin reduces risk of major vascular events but increases risk of major hemorrhage compared with aspirin alone |
CHADS2 score | |||||
---|---|---|---|---|---|
Scoring system | Stroke rates associated with CHADS2 score | ||||
Risk factor | Points | Risk score | Adjusted stroke rate (%/y)a, b (95 % CI) | Risk of stroke | |
C | CHF | 1 | 0 | 1.9 (1.2, 3.0) | Low |
H | Hypertension | 1 | 1 | 2.8 (2.0, 3.8) | Moderate |
A | Age ≥75 y | 1 | 2 | 4.0 (3.1, 5.1) | |
D | Diabetes | 1 | 3 | 5.9 (4.6, 7.3) | |
S2
| Prior stroke/TIA | 2 | 4 | 8.5 (6.3, 11.1) | High |
5 | 12.5 (8.2, 17.5) | ||||
6 | 18.2 (10.5, 27.4) | ||||
CHA2DS2-VASc score | |||||
Scoring system | Stroke rates associated with CHA2DSs-VASc score | ||||
Risk factor | Points | Risk score | TE rate during 1 year (% [95 % CI])c, d
| Risk of stroke | |
C | CHF/LV dysfunction | 1 | 0 | 0 | Low |
H | Hypertension | 1 | 1 | 0.6 (0.0, 3.4) | Moderate |
A2
| Age ≥75 y | 2 | 2 | 1.6 (0.3, 4.7) | |
D | Diabetes | 1 | 3 | 3.9 (1.7, 7.6) | High |
S2
| Prior stroke/TIA/TE | 2 | 4 | 1.9 (0.5, 4.9) | |
V | Vascular disease (prior MI, PAD, or aortic plaque) | 1 | 5 | 3.2 (0.7, 9.0) | |
A | Age 65–74 y | 1 | 6 | 3.6 (0.4, 12.3) | |
Sc | Sex category (female sex) | 1 | 7 | 8.0 (1.0, 26.0) |
Risk factor | Points | |
---|---|---|
H | Hypertension | 1 |
A | Abnormal renal and liver function (1 point each) | 1 or 2 |
S | Stroke | 1 |
B | Bleeding | 1 |
L | Labile INRs | 1 |
E | Elderly (age >65 y) | 1 |
D | Drugs or alcohol (1 point each) | 1 or 2 |
Risk score | Bleeds per 100 patient-years | Risk of bleeding |
0 | 1.13 | Low |
1 | 1.02 | Moderate |
2 | 1.88 | |
3 | 3.74 | High |
4 | 8.70 | |
5 | 12.50 |
Application of treatment guidelines to clinical practice
Hypothetical patient case 1: Balancing the benefit of thromboprophylaxis with the risk of bleeding
Case discussion
Criteria | Dabigatran [28] | Rivaroxaban [30] | Apixaban [29] | Edoxaban [27] |
---|---|---|---|---|
Anemia | Contraindicated | Contraindicated in patients with hemoglobin <10 g/dL | Contraindicated in patients with hemoglobin <9 g/dL | NA |
Bleeding risk | Contraindicated in patients with hemoglobin <10 g/dL and patients with active pathologic bleeding | |||
Can cause serious and sometimes fatal bleeding | ||||
Concomitant drugs affecting hemostasis can increase bleeding risk, including platelet aggregation inhibitors, heparin, fibrinolytic therapy, and chronic use of NSAIDs | Concomitant drugs affecting hemostasis can increase bleeding risk, including NSAIDs, heparin, aspirin, platelet aggregation inhibitors, other antithrombotic drugs, and fibrinolytic therapy | Concomitant drugs affecting hemostasis can increase bleeding risk, including platelet aggregation inhibitors, other antithrombotic drugs, heparin, thrombolytic agents, SSRIs, SNRIs, and chronic use of NSAIDs | Concomitant use of drugs affecting hemostasis may increase the risk of bleeding, including aspirin and other antiplatelet agents, other antithrombotic agents, fibrinolytic therapy, and chronic use of NSAIDs | |
Interruption for surgery/procedures | To reduce risk of bleeding, discontinue dabigatran 1–2 d (CrCl ≥50 mL/min) or 3–5 d (CrCl <50 mL/min) before invasive or surgical procedures | To reduce risk of bleeding, discontinue rivaroxaban at least 24 h prior to surgical or other invasive procedures | To reduce risk of bleeding, discontinue apixaban at least 48 h prior to elective surgery or invasive procedures with a moderate or high risk of unacceptable or clinically significant bleeding, and at least 24 h prior to elective surgery or invasive procedures with a low risk of bleeding or where the bleeding would be noncritical in location and easily controlled | To reduce the risk of bleeding, discontinue edoxaban at least 24 hours before invasive or surgical procedure |
Drug interactions | Avoid concomitant use with P-gp inducers (e.g., rifampin) | Avoid concomitant use with combined P-gp and strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) or inducers (carbamazepine, phenytoin, rifampin, St. John’s wort) | Reduce apixaban dosage to 2.5 mg bid or avoid concomitant use with strong dual inhibitors of CYP3A4 and P-gp (e.g., ketoconazole, itraconazole, ritonavir, or clarithromycin) | Co-administration with anticoagulants, antiplatelet drugs and thrombolytics may increase the risk of bleeding |
For patients with moderate renal impairment (CrCl 30–50 mL/min), dabigatran dose may be reduced to 75 mg bid when administered concomitantly with the P-gp inhibitor dronedarone or systemic ketoconazole. Dose adjustment not required with P-gp inhibitors (verapamil, amiodarone, quinidine, and clarithromycin) | For patients with CrCl 15–50 mL/min, rivaroxaban may be used concomitantly with combined P-gp and weak or moderate CYP3A4 inhibitors (e.g., amiodarone, diltiazem, verapamil, quinidine, ranolazine, dronedarone, felodipine, erythromycin, and azithromycin) only if the potential benefit justifies the potential risk | Avoid concomitant use with strong dual inducers of CYP3A4 and P-gp (e.g., rifampin, carbamazepine, phenytoin, St. John’s wort) because such drugs will decrease exposure to apixaban | Avoid concomitant use with rifampin | |
Avoid concomitant use with P-gp inhibitors in patients with severe renal impairment (CrCl 15–30 mL/min) | No dose reduction is recommended in patients taking concomitant P-gp inhibitors | |||
Hepatic impairment | Large intersubject variability but no evident consistent change in exposure or PD in patients with moderate hepatic impairment | Avoid use in moderate and severe hepatic impairment or with any hepatic disease associated with coagulopathy | No dose adjustment necessary in patients with mild hepatic impairment | Use of edoxaban in patients with moderate or severe hepatic impairment is not recommended as these patients may have intrinsic coagulation abnormalities. No dose reduction is required in patients with mild hepatic impairment |
No dosing recommendations available for patients with moderate hepatic impairment because of lack of clinical experience with apixaban in these patients | ||||
Not recommended in patients with severe hepatic impairment | ||||
Renal elimination | 80 % [69] | 36 % [68] | 50 % [57] | |
Renal impairment | Contraindicated in patients with CrCl <15 mL/min; reduce dosage to 75 mg bid if CrCl 15–30 mL/min | Avoid use in patients with CrCl <15 mL/min | Reduce dosage to 2.5 mg bid in patients with serum creatinine ≥1.5 mg/dL and either age ≥80 years or body weight ≤60 kg | Reduce edoxaban dose to 30 mg qd in patients with CrCl 15-50 mL/min. Not recommended in patients with CrCl<15 mL/min |
5 mg bid in patients with ESRD maintained on hemodialysis. Reduce dose to 2.5 mg bid in patients with ESRD aged ≥80 years or body weight ≤60 kg | ||||
Reversal antidote | In progress; none approved for use | In progress; none approved for use | In progress; none approved for use | In progress; none approved for use |
Tested reversal strategiesa
| Dialysis [54] | PCC (Cofact) [50] | rFVIIa [51] | rFVIIa [56] |
aPCC (FEIBA®) [55] | aPCC (FEIBA®) [53] | aPCC (FEIBA®) [51] | aPCC (FEIBA®) [56] | |
PER977 (when available) [76] | Andexanet alfa (when available) [52] | Activated charcoal [71] | PPSB-HT [56] | |
PER977 (when available) [76] | ||||
PER977 (when available) [76] |