The use of new oral anticoagulants (NOACS) as an alternative to vitamin K antagonists to prevent stroke in patients with non-valvular atrial fibrillation (AFib) has shown several potential benefits, including fewer food and drug interactions, an improved efficacy/safety ratio, and no need for regular monitoring, among other things. However, the use of NOACS requires that both physicians and patients learn how to use these drugs effectively and safely in clinical practice, and to date little unified guidance on specific clinical situations exists. In addition, as with any new class of drugs, there are many areas where continued research and clinical trials are needed.

In a first attempt to coordinate a unified way of addressing NOAC use among physicians, the European Heart Rhythm Association  has released a “practical guide” focused on 15 specific clinical scenarios ranging from starting the drugs to treating AFib patients with cancer. Specifically, the guide addresses:

1. Practical start-up and follow-up scheme for patients on NOACs
2. How to measure the anticoagulant effect of NOACs
3. Drug-drug interactions and pharmacokinetics of NOACs
4. Switching between anticoagulant regimens
5. Ensuring compliance of NOAC intake
6. How to deal with dosing errors
7. Patients with chronic kidney disease
8. What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding
9. Management of bleeding complications
10. Patients undergoing a planned surgical intervention or ablation
11. Patients undergoing an urgent surgical intervention
12. Patients with AFib and coronary artery disease
13. Cardioversion in a NOAC-treated patient
14. Patients presenting with acute stroke while on NOACs
15. NOACs vs. vitamin K antagonists in AFib patients with a malignancy

To date dabigatran (Pradaxa), rivaroxaban (Xarelto) and apixaban (Eliquis) are the three NOACs approved for use in the U.S. and Europe. The guide stresses the importance of patient education when it comes to patient compliance and also provides a comprehensive table on measures to enact in case of bleeding that divides bleeds into non-life-threatening and life-threatening categories.

"This guide is a much-needed first step in answering the many questions cardiologists, surgeons and other health professionals are asking about NOAC use," said Richard Kovacs, MD, FACC, who is heading up the American College of Cardiology's (ACC's) new Anticoagulation Initiative. "Our data show a definite gap in care when it comes to meeting guideline recommendations for prescribing anticoagulants. A unified approach to defining optimal use could go a long way in helping to close these gaps."

According to Kovacs, the ACC's Anticoagulation Initiative hopes to build on the work of the EHRA work group, through the development of resources and tools for physicians and patients. The College recently launched an Anticoag Evaluator mobile app to help providers calculate stroke and bleeding risk and identify anticoagulant options. In addition, several AFib education programs are already underway and a shared-decision making tool for patients and providers will be available later this year. In addition, the Anticoagulation Initiative work group has plans to bring together key U.S. stakeholders to further flesh out answers to some of the biggest NOAC questions this fall.

"The EHRA acknowledges that there are still gaps, unaddressed questions and areas of uncertainty/debate," said Kovacs. "Hopefully we can all work together to continue this productive discussion and provide additional guidance moving forward.

Meanwhile, a study published May 2 in Circulation  found that in AFib patients, the benefits of apixaban compared with warfarin on stroke or systemic embolism, bleeding and mortality appeared similar across the broad range of centers’ and patients’ predicted quality of International Normalized Ratio control.

Keywords: Vitamin K, Uncertainty, Coronary Artery Disease, Stroke, Neoplasms, Follow-Up Studies, Morpholines, Pyrazoles, Pyridines, Benzimidazoles, Embolism, Pyridones, United States, Patient Compliance, Renal Insufficiency, Chronic