Advances in Atrial Fibrillation Care: From Diagnostics to Anticoagulants

Atrial fibrillation is a major cause of life-threatening conditions such as cerebral infarction, prompting increased interest in anticoagulants for treatment and prevention. Warfarin, once the go-to therapy, has largely been replaced by non-vitamin K oral anticoagulants (NOACs), first developed around 2011 to overcome its limitations. Despite the recent rise in NOAC prescriptions, awareness remains low, with many patients only starting treatment after severe complications arise.

The "Korea Atrial Fibrillation Fact Sheet 2024," published by the Korean Society of Arrhythmia, highlights a notable increase in atrial fibrillation cases among elderly individuals. For those aged 80 and older, prevalence jumped from 7.4% in 2013 to 12.9% in 2022.

Hit News interviewed Professor Ki-Hong Lee, Medical Information Director at the Korean Society of Arrhythmia and contributor to the fact sheet, to discuss the state of atrial fibrillation in Korea, the role of NOACs, and treatment strategies for elderly patients.

"Atrial fibrillation is characterized by irregular heart rhythms due to multiple abnormal signals originating within the heart, disrupting the sinoatrial node's normal function. Instead of one signal per second, atrial fibrillation may cause the heart to receive over 250 signals per second. This irregularity can lead to cerebral infarction as blood clots form, which may travel to the brain and cause a stroke."

"The primary treatment for preventing cerebral infarction and stroke is anticoagulant therapy, which helps reduce the risk of clot formation. According to the 'Atrial Fibrillation Fact Sheet', recently published by the Korean Society of Arrhythmia, approximately 24% of cerebral infarctions are caused by atrial fibrillation, and 20% can be prevented with the use of anticoagulants alone.

In the past, warfarin was the most commonly used anticoagulant to prevent blood clots. However, it posed several inconveniences, such as the need for regular blood tests, dosage adjustments, and dietary restrictions. Some physicians prescribed aspirin as an alternative, but recent studies have shown that it is not effective in preventing cerebral infarction.

To overcome these limitations, non-vitamin K oral anticoagulants (NOACs) were developed, starting with the introduction of dabigatran (original brand Pradaxa) in 2011. Since then, other NOACs such as rivaroxaban (original brand Xarelto), apixaban (original brand Eliquis), and edoxaban (original brand Lixiana) have been sequentially introduced and are now widely used for the treatment of atrial fibrillation."

"The Korean Society of Arrhythmia decided to release its first fact sheet this past June to enhance its academic representation. Initial discussions began about 10 years ago, using foreign data as a reference. Professors Eue-Keun Choi and Jaemin Shin from Seoul National University Hospital, along with myself, took the lead in shaping the content and structure of the fact sheet.

This fact sheet involved over 30 contributing professors and contains key data and research results specific to Korea, adding to its credibility. We held numerous meetings to ensure the accuracy of the statistics and data, carefully reviewing them to clearly define terms. We plan to continue updates and further work on this project moving forward."

"The aging population and improved diagnostic technology, such as continuous heart monitoring and wearable devices, have contributed to this rise. These improvements enable the recording of heart activity not just in a clinical setting, but throughout daily life. Additionally, more convenient methods such as single-electrode devices that adhere to the skin, and wearable technology like smartwatches, have emerged.

These technologies have significantly improved the diagnosis rate of atrial fibrillation, and with growing awareness among healthcare professionals, opportunities to detect and treat patients early are also increasing."

"The fact sheet shows that 85% of patients who need anticoagulants after a cerebral infarction aren’t prescribed them at the time of diagnosis, and 51% delay treatment for six months or more. One reason is that many patients are unaware of the seriousness of atrial fibrillation and are reluctant to start complex treatment regimens.

Additionally, some physicians hesitate to prescribe anticoagulants due to concerns about potential side effects, such as brain hemorrhage or gastrointestinal bleeding. In some cases, aspirin is still mistakenly prescribed as a substitute, despite its ineffectiveness in preventing stroke."

"Lixiana has been shown to be both effective and safe, particularly in elderly patients. Data from the ENGAGE-AF trial and the ELDERCARE study support its use, even in patients over 80 years old with a high risk of bleeding. Its favorable safety profile and efficacy are reflected in both the New England Journal of Medicine and Korean NOAC guidelines."

"To better understand prescribing NOACs for elderly patients, let’s consider an example. Imagine a man in his 90s visiting the clinic. He has a history of cerebral hemorrhage and has undergone surgery for gastrointestinal issues. He walks slowly with a shuffle and is currently taking medication for high blood pressure and cerebral hemorrhage but not for diabetes.

If this patient has atrial fibrillation, prescribing the appropriate medication requires a highly cautious approach. Elderly patients are often frail, which raises the likelihood of side effects like bleeding when using medications. Moreover, after the drug is metabolized, it needs to be excreted, but due to natural decline in kidney function in older adults, the drug may not be eliminated efficiently.

This can lead to accumulation in the body, significantly increasing the risk of side effects in those over 90 years old with compromised kidney function. As a result, physicians often deliberate whether to adjust the dosage or even withhold the medication entirely for elderly patients.

In this context, drugs like Lixiana, which have clinical data specifically for elderly populations, are highly valued by healthcare providers. Lixiana has demonstrated efficacy even at lower doses, and its suitability for patients with reduced kidney function has been proven. Compared to warfarin and other medications, Lixiana offers clear advantages by providing robust safety and efficacy data, making it a favorable option for managing atrial fibrillation in older patients."

"In the case of NOACs, adherence to medication reaches 80% within the first year of treatment, but drops to 65% after one year.

Improving adherence requires a significant shift in patient awareness. Patients need to fully understand their condition and recognize the importance of treatment. While a lot of information is available on platforms like YouTube, much of it is unverified, raising concerns about its reliability. Since the public tends to consume information based on interest, there’s a higher chance they may encounter content lacking scientific evidence.

To effectively improve adherence, it’s essential to clearly communicate the importance of the disease and treatment to patients. They need to understand why it's crucial to continue their medication. I believe that to enhance the credibility of information on platforms like YouTube, healthcare professionals should contribute by providing scientifically based content.

Additionally, making medication easier to take is important. Reducing the frequency of doses is a key factor. For example, it can be inconvenient to take multiple doses while traveling, so reducing the intake to once or twice a day is beneficial.

The size of the medication also plays a role. Large pills can be difficult to swallow, leading patients to avoid taking them. Moreover, the packaging and labeling should be clear to ensure that patients can take the medication accurately without confusion."

"NOACs are expected to continue playing a key role in atrial fibrillation treatment. In fact, it will likely become unusual not to use them. I also believe there will be advancements in the diagnosis and management of atrial fibrillation. Recently, technology has been improving to predict and detect undiagnosed atrial fibrillation, and there are ongoing developments in the field of procedures as well. I hope these procedures will evolve to become easier, safer, and minimize recurrence. Lastly, since both treatment and management are crucial, I expect that a system capable of providing both aspects together will be established."