Reversal Agents in the Era of NOACs

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

New oral anticoagulants - possible extension to other indications (Review)

Anticoagulant treatment is necessary in various conditions, with curative or preventive purposes. Until recently, the only oral anticoagulants available have been vitamin K antagonists. To overcome the disadvantages of the antivitamin K oral anticoagulants, new oral anticoagulants (NOACs) have been developed and included in clinical trials. After more than 60 years of using vitamin K antagonists, the introduction of NOACs represent a medical breakthrough, with promising prospects. Due to their promising results and better safety profile, NOACs have become an appealing alternative to vitamin K antagonists in a short period of time. NOACs have been approved for the prevention and treatment of venous thromboembolism and for the prevention of stroke in patients with nonvalvular atrial fibrillation. Starting with postoperative venous thromboprophylaxis after hip replacement surgery, NOACs have been approved also for other clinical situations. Rivaroxaban is the first oral anticoagulant approved to be used in combination with an antiplatelet agent to prevent atherothrombotic events in adults with coronary artery disease and/or peripheral artery disease. However, further investigation is needed to establish which group of patients would benefit most from this medical approach. Furthermore, preliminary studies have shown that NOACs seem to be a reasonable choice of anticoagulation for patients with cancer, but further studies are expected.

Intake of NOAC is associated with hematoma expansion of intracerebral hematomas after traumatic brain injury

PURPOSE

Novel oral anticoagulants are increasingly replacing vitamin K antagonists in the prophylaxis of thromboembolism as they are associated with lower incidence of spontaneous intracerebral hematomas and they do not require drug level monitoring. However, management dilemmas are apparent in patients on novel oral anticoagulants who have developed intracerebral hematomas after traumatic brain injury, since clinical experience with their reversal strategies is limited.

METHODS

We retrospectively studied 90 patients with traumatic intracerebral hematomas undergoing treatment at the surgical intensive care unit of the BG University Clinic Bergmannsheil in Bochum between 2015 and 2018. We analyzed potential prognostic factors for their radiological (expansion of intracerebral hematoma) and clinical (patients' outcome) course, in particular the role of novel oral anticoagulants.

RESULTS

71.1% of patients were male; mean age was 67.3 years. Hematoma's expansion occurred in 35.9% of our patients, whereas 62.2% of our cohort showed a favorable outcome, defined as Glasgow Outcome Scale 4 and 5. Intake of novel oral anticoagulants was associated with a higher rate of hematoma's expansion compared to patients on vitamin K antagonists (p = 0.05) or to patients with normal coagulation status (p = 0.002). A younger age (p < 0.001) was identified as the sole independent prognostic factor for a more favorable outcome, after excluding our cases, who underwent a cardiopulmonary resuscitation.

CONCLUSIONS

Our data showed a higher rate of hematoma's expansion in patients with traumatic intracerebral hematomas on novel oral anticoagulants vs. vitamin K antagonists and recommend the consideration of prophylactic reversal of the novel oral anticoagulants at admission. Larger prospective trials are warranted to conclude whether the current specific reversal protocols are safe and effective.

A Narrative Review of Nonvitamin K Antagonist Oral Anticoagulant Use in Secondary Stroke Prevention

The prevalence of atrial fibrillation (AF), the most common cardiac arrhythmia, increases with age, predisposing elderly patients to an increased risk of embolic stroke. With an increasingly aged population the number of people who experience a stroke every year, overall global burden of stroke, and numbers of stroke survivors and related deaths continue to increase. Anticoagulation with vitamin K antagonists (VKAs) reduces the risk of ischemic stroke in patients with AF; however, increased bleeding risk is well documented, particularly in the elderly. Consequently, VKAs have been underused in the elderly. Alternative anticoagulants may offer a safer choice, particularly in patients who have experienced previous stroke. The aim of this narrative review is to examine available evidence for the effective treatment of patients with AF and previous cerebral vascular events with non-VKA oral anticoagulants, including the most appropriate time to start or reinitiate treatment after a stroke, systemic embolism, or clinically relevant bleed. For patients with AF treated with oral anticoagulants it is important to balance increased protection against future stroke/systemic embolism and reduced risk of major bleeding events. For patients with AF who have previously experienced a cerebrovascular event, the use of oral anticoagulants alone also appears more effective than low-molecular weight heparin (LMWH) alone or LMWH followed by oral anticoagulants. Available data suggest that significant reduction in stroke, symptomatic cerebral bleeding, and major extracranial bleeding within 90 days from acute stroke can be achieved if oral anticoagulation is initiated at 4-14 days from stroke onset.

Oral anticoagulant use in cardiovascular disorders: a perspective on present and potential indications for rivaroxaban

BACKGROUND

Four non-vitamin-K-antagonist oral anticoagulants (NOACs) have been approved for use in various cardiovascular indications. The direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors apixaban, edoxaban and rivaroxaban are now increasingly used in clinical practice. For some of these agents, available data from real-world studies support the efficacy and safety data in phase III clinical trials.

OBJECTIVES

This review aims to summarize the current status of trials and observational studies of oral anticoagulant use over the spectrum of cardiovascular disorders (excluding venous thrombosis), provide a reference source beyond stroke prevention for atrial fibrillation (AF) and examine the potential for novel applications in the cardiovascular field.

METHODS

We searched the recent literature for data on completed and upcoming trials of oral anticoagulants with a particular focus on rivaroxaban.

RESULTS

Recent data in specific patient subgroups, such as patients with AF undergoing catheter ablation or cardioversion, have led to an extended approval for rivaroxaban, whereas the other NOACs have ongoing or recently completed trials in this setting. However, there are unmet medical needs for several arterial thromboembolic-related conditions, including patients with: AF and acute coronary syndrome, AF and coronary artery disease undergoing elective percutaneous coronary intervention, coronary artery disease and peripheral artery disease, implanted cardiac devices, and embolic stroke of unknown source.

CONCLUSION

NOACs may provide alternative treatment options in areas of unmet need, and numerous studies are underway to assess their benefit-risk profiles in these settings.