Novel anticoagulants in atrial fibrillation stroke prevention

Abstract

This review article evaluates novel oral anticoagulants in comparison with warfarin for thromboembolism prophylaxis in patients with atrial fibrillation (AF). AF is the most frequently diagnosed arrhythmia in the United States. The most serious side effect of AF is stroke. Warfarin has several decades of proven efficacy in AF-related stroke prevention but the drug's numerous drawbacks make its implementation difficult for practitioners and patients. The difficulties of warfarin have prompted the development of alternative anticoagulants for AF-related stroke prevention with better efficacy, safety, and convenience. The oral direct thrombin inhibitor, dabigatran, and the oral factor Xa inhibitors, rivaroxaban and apixaban, have been evaluated in a large phase III trial. Dabigatran, rivaroxaban and apixaban were shown to be noninferior compared with warfarin in the prevention of stroke. Dabigatran and apixaban were found to be statistically superior to warfarin. All three may also have a better safety profile than warfarin. In conclusion, novel anticoagulants have a different pharmacologic profile compared with warfarin that may eliminate many of the treatment inconveniences. Practitioners must also be aware of the disadvantages these new drugs possess when choosing a management strategy for their patients. Drug selection may become clearer as these new drugs are used more extensively.

Oral Anticoagulation Therapy for Elderly Patients With Atrial Fibrillation

“…3 Many have attributed bleeding risks particularly to warfarin therapy, raising expectations that a new generation of antithrombotic agents would offer safer anticoagulation. 4 Yet, although the selective direct factor inhibitors such as dabigatran, apixaban, rivaroxaban, and edoxaban provide advantages in administration, they do not eliminate bleeding risks. In the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) Trial a direct thrombin inhibitor, dabigatran, was compared with warfarin.…”

New oral anticoagulants for Atrial Fibrillation

“…13,22 Dabigatran is formulated as encapsulated pellets with a tartaric acid core to enhance its oral absorption and to ensure consistent and pharmacologically desirable concentrations. 23 Crushing or breaking the capsules and administration via a nasogastric (NG) tube should be avoided, because pellet administration outside of the capsule can increase bioavailability by up to 75%. 13,23 In patients with AF, dabigatran 150 mg is taken twice daily with or without food.…”

“…23 Crushing or breaking the capsules and administration via a nasogastric (NG) tube should be avoided, because pellet administration outside of the capsule can increase bioavailability by up to 75%. 13,23 In patients with AF, dabigatran 150 mg is taken twice daily with or without food. A reduced dose of 75 mg is recommended if the patient's creatinine clearance (CrCl) is 15 to 30 mL/ minute.…”

Inhibitory Effect of Triterpenoids from Panax ginseng on Coagulation Factor X

“…Selective inhibition of FXa was unable to affect the pre-existing thrombin level, and activation and aggregation of the platelets reduced the risk of bleeding when compared with traditional anti-coagulants [ 2 ]. In addition, FXa plays a vital role in amplifying the process, and is endued with the ability to produce more than one thousand thrombin molecules [ 2 , 4 ]. Furthermore, currently available FXa inhibitors approved by Food and Drug Administration such as rivaroxaban, apixaban and epibaxaban, have been reported to still demonstrate flaws including bleeding risks, narrow clinical applications and drug-drug interactions [ 2 ].…”