Jeffrey Tabas, MD, on Anticoagulation Therapy for Patients With Atrial Fibrillation

In this podcast, Jeffrey Tabas, MD, discusses the challenge of when to initiate anticoagulation therapy and to which patients, which he also talked about during his session at the American College of Emergency Physicians 2021. 

For more parts of this series, visit our resource center for the American College of Emergency Physicians 2021 Scientific Assembly.

Additional Resource:

• Tabas J. Atrial fibrillation 2021: don’t miss a beat. Talk presented at: American College of Emergency Physicians 2021; October 25-28, 2021; Boston, Massachusetts. https://cdn.base.parameter1.com/files/base/ascend/hh/document/2021/10/ACEP21_DigitalProgram.616f40ccac5fc.pdf
• Writing Group Members, January CT, Wann LS, et al. 2019 AHA/ACC/HRS focused update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Heart Rhythm. 2019;16(8):e66-e93. https://doi.org/10.1016/j.hrthm.2019.01.024
• Kotalczyk A, Lip GY, Calkins H. The 2020 ESC guidelines on the diagnosis and management of atrial fibrillation. Arrhythm Electrophysiol Rev. 2021;10(2):65-67. https://doi.org/10.15420/aer.2021.07
• Atzema CL, Jackevicius CA, Chong A, et al. Prescribing of oral anticoagulants in the emergency department and subsequent long-term use by older adults with atrial fibrillation. CMAJ. 2019;191(49):E1345-E1354. https://doi.org/10.1503/cmaj.190747

Jeffrey Tabas, MD, is a professor of emergency medicine at the University of California, San Francisco’s School of Medicine, an emergency medicine physician at Zuckerberg’s San Francisco General Emergency Department, the director of faculty development for the Department of Emergency Medicine, and the director of Outcomes and Innovations for the UCSF Office of Continuing Medical Education.

TRANSCRIPT:

Amanda Balbi: Hello and welcome to a special series of Podcasts360. I’m your moderator, Amanda Balbi. In this 6-part series, we will be speaking with Dr Jeffrey Tabas, who is a professor of emergency medicine at the University of California, San Francisco’s School of Medicine, an emergency medicine physician at Zuckerberg’s San Francisco General Emergency Department, the director of faculty development for the Department of Emergency Medicine, and the director of Outcomes and Innovations for the UCSF Office of Continuing Medical Education.

He recently presented a session on atrial fibrillation at the American College of Emergency Physicians 2021 Scientific Assembly. In part 3 of this podcast series, he talks about rate control among patients presenting with atrial fibrillation in the emergency department.

Let’s listen in as he answers our questions.

Another challenge you spoke about during your session was about anticoagulation therapy, specifically which patients qualify for treatment. Can you talk a little more about that?

Jeffrey Tabas: I think it's important to lay out that practicing physicians are not world experts. Whenever we implement any recommendations, it's important to recognize that they need to be systematic and simple. The less systematic and the more complex they are, I think the more variability the less recommendations are followed and the potential for worse care of the patient. 

The way I like to approach problems like anticoagulation for atrial fibrillation, which is very complicated, is to try and boil it down. I also give a case for this. This was a tennis partner of mine about 50 years old, who kept looking at his heart rate on his smartwatch and he'd been diagnosed with intermittent atrial fibrillation. He didn't have any risk factors that needed anticoagulation but wanted to know about getting his heart rate controlled.

Well, it turned out that he was at work and through a massive clot and was rushed to the hospital and had thrombolysis for his clot and good recovery, but he was fortunate because he happened to get emergently to a stroke center. It was an unusual form of a clot. The posterior circulation, which doesn't give you the weakness of the arm or the facial droop; it just makes you unresponsive. Fortunately, it was a good center. They recognized this, they treated him, and he had a great recovery.

But it made me want to really focus on who needs anticoagulation. It's a very complicated issue. If you think about it, 1 out of every 3 people in their lifetime will have atrial fibrillation. And by age 80, about a quarter of us will be in atrial fib. All of us are significant risk for this. If you think about it, 5 million people in the US have atrial fibrillation, it puts you at high risk for stroke—like at least a 5-fold higher lifetime risk of stroke—than those without afib. Anticoagulation decreases that risk of stroke significantly.

We also know that about 40% of people who are at intermediate to high risk of stroke, are not anticoagulated. So, we have a ton of people who are risk of stroke; 20% to 30% of strokes come from atrial fibrillation. We can impact that, and there are a lot of people that we are not anticoagulating. 

I think it's important to look at the role of the emergency department in this. There is some research that suggests that when emergency providers, we typically don't initiate long-term medications from the emergency department, but there is some indication that when people initiate anticoagulation in the ED to appropriate patients, compared with telling them to see their doctors in outpatient and ask them about this, that there are higher rates of compliance and use of anticoagulation. There's a suggestion that initiating it from the emergency department is beneficial. 

This is analogous to treating patients who have opioid dependence with medically assisted treatment for opioid dependence. They found that, when they're seen in the emergency department and told to go to a clinic and start treatment like methadone or buprenorphine, they don't do as well as when that treatment is started in the ED, specifically buprenorphine. It makes sense. If you're in an emergency situation and the doctor says, “I'm worried about you. Here's a prescription that will help you,” it probably jolts you into activity a little better—at least a portion of patients that jolts them into activity a little better—than saying go back into the medical system and start getting treatment for this. That's one thought.

The other thought is probably a lot of physicians don't anticoagulant because it's a complicated assessment. There's something called the CHA2DS2-VASc score. So, right away that's complicated. It's not a simple pneumonic, and it's even more complicated because there's this bizarre statistical phenomenon where a woman, just from being female, gets 1 point and a male gets no points. That's because when, in higher risk patients, women have higher risk of stroke. If you are old and have heart failure, you're at a fairly high risk of stroke and you're at even higher risk of stroke as a woman, but that does not impact initiation of anticoagulation; Those factors don't affect risk at the lower end. 

So, they've added this very complicated calculation where men get 0 points without risk; women get one point. You are only supposed to anticoagulate if a man has 1 point or a woman has 2 points. Are you confused? Yes, you are. That's crazy! It's insane! Really, I mean it's insane for a practicing physician to have to use 2 different cut-off levels for 2 different values that don't have impact.

The way I approached this is…in the old days, we used to talk about lone Afib. Lone Afib was a patient who was younger than 65 years who did not have high blood pressure, diabetes, or heart failure, and who did not have vascular disease—that means a previous stroke, MI, or peripheral vascular disease, and they definitely didn't have valvular disease. Patients with valvular disease are at the highest risk of stroke, by far. Any patient with valvular disease or a valve replacement needs to be on anticoagulation if they’re in atrial fibrillation.

They're the highest risk of all. So, if you were young (I'm going to call “young” less than 65, as I approach the age of 65), if you don't have comorbidities like high blood pressure, diabetes, or heart failure, and you don't have previous vascular or thromboembolic disease, you have lone Afib and you don't need to be anticoagulated—whether you're a man or woman. If you have any of those, there's pretty good evidence that you should be anticoagulated. 

The guidelines from the American College of Cardiology and Heart Association say definitely anticoagulate someone with 2 of those and consider anticoagulation in someone with 1 of those. However, the European Society of Cardiology, which was published in 2020, says it's a fairly good recommendation to anticoagulate anyone with 1 of those. I think that's the best. 

I mean, realize that if they just have 1 thing, if they just have hypertension and they're young and they have any significant concerns for bleeding, like they say play ice hockey or something, you may want to not anticoagulate them; they're borderline. But if they don't have concerns, they will benefit from anticoagulation. Basically, the only patients who shouldn't be considered for anticoagulation are the patients with lone Afib, the ones who have none of those.

People are not going to like that I'm calling it lone Afib because that's an old term that they got rid of, but I will tell you that is the best way for doctors to think about this. Lone Afib you don't need to be anticoagulated; everyone else should probably be anticoagulated or at least have the discussion about the risks and benefits of anticoagulation.

To do this from the emergency department, we know that patients have better compliance, you don't want to just initiate a prescription, because you need to make sure you're initiating prescription and someone who can get follow-up, that their insurance will cover the anticoagulant, that there’s support from your system to then go evaluate the patient, that you've considered they're bleeding risks, that you've had this discussion.

But at least it pushes you to think about this more, to push your organization to develop an integrated approach. One of the things that the European society guidelines really emphasize is an integrated approach to all patients with atrial fibrillation. They recommend all of them should have an ECHO of their heart, all of them should have assessment for anticoagulation and need for stroke risk and bleeding risk. I think that is great to bring back to your shop.

You will consider carefully that patient who presents you with atrial fibrillation whether they need to be anticoagulated and, at the very least, strongly encourage them if they have any of these risk factors. Some of the things that both society guidelines say shouldn't be a consideration is the burden of atrial fibrillation, meaning if they have it intermittently or persistently that they're still at risk. There is an increased risk the more atrial fibrillation you have. But the risk is significant enough that, if you pop in and out of atrial fibrillation even occasionally, you're at risk for stroke.

Less not take that into account as much. Maybe you're right on the borderline of deciding, and you have rare atrial fibrillation, you might wait. But they've also commented that in the first 4 months of patients who are low risk, they often convert to higher risk. So, if you reassess them at 6 months, they then are now either older past the cutoff where they have high blood pressure now, or they converted from prediabetes or diabetes or…there's something that has changed that now puts them in a risk category.

So, again, this is a very preventable disease. Stroke is a very preventable disease, and we need to get better at recognizing the high-risk patients and anticoagulating them and decreasing their risk.

Amanda Balbi: I think that was so helpful. It blows my mind that the percentage of people with Afib or high risk for a fib is so high, and yet the prescriptions are so low.

Jeffrey Tabas: It's mind boggling. I don't know if that's more mind boggling or the fact that the calculation for this is so complicated. I think it's more mind boggling that the fact that it's so complicated…and I bet that explains at least a third of patients who don't get prescriptions. I mean, I don't know. I'm not going to do that research, but I can just tell you from experience in medicine for the past 30 years, that's the case. I know it's the case.

Amanda Balbi: Well, especially if you think about it, who sees the patients more often? The primary care provider, you know?

Jeffrey Tabas: Yes, exactly. It isn’t the Afib specialist.

Amanda Balbi: Thank you so much for speaking with me today. And for our listeners, stay tuned for the subsequent parts of this series.