CardioNerds Atrial Fibrillation Series Co-Chairs Dr. Colin Blumenthal (University of Pennsylvania Cardiology fellow) and Dr. Kelly Arps (Duke University Electrophysiology Fellow) join the 2023 atrial fibrillation guideline writing committee Chair Dr. José Joglar (UT Southwestern) and Vice Chair Dr. Mina Chung (Cleveland Clinic). They review the key takeaways from the 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation.  Audio editing by CardioNerds academy intern, student doctor Pace Wetstein.

This podcast was developed in collaboration with the American Heart Association. For more on these guidelines, access the AHA Science News AF Guideline landing page.

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

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CardioNerds co-founder Dr. Amit Goyal, series co-chair Dr. Colin Blumenthal, and episode lead Dr. Anushka Tandon to discuss pharmacologic anticoagulation options in atrial fibrillation with Drs. Ashley Lochman and Chris Domenico. The case-based review helps clarify some key concepts, such as when warfarin is preferred for anticoagulation, who may be a good DOAC (direct-acting oral anticoagulant) candidate, how to choose an appropriate DOAC agent, and how to manage anticoagulation therapy in patients already on antiplatelet therapies. Notes were drafted by Dr. Anushka Tandon. The episode audio was edited by student Dr. Shivani Reddy.

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This episode was planned and recorded prior to the release of the 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Please refer to this guideline document for the most updated recommendations.

We have collaborated with VCU Health to provide CME. Claim free CME here!

This episode is made possible with support from Glass.Health – The first digital notebook designed for doctors. Follow @GlassHealthHQ for the latest product updates!

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

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In which cases is warfarin preferred over DOACs in patients with atrial fibrillation?

What patient-specific factors should be considered when deciding whether someone is a good candidate for DOAC therapy?

What safety profile and bleeding risk considerations exist for warfarin versus DOACs?

What is the recommended anti-thrombotic approach for patients with indications for both antiplatelet therapy and anticoagulation (for example, patients with atrial fibrillation undergoing PCI)?

What’s the scoop on factor XI, which appears to be clinically important for thrombosis but not hemostasis, as a potential drug target? Might this be the future of anticoagulation pharmacotherapy?

Dr. Daniel Ambinder (CardioNerds Co-Founder), Dr. Kelly Arps (Series Co-Chair and EP fellow at Duke University), Dr. Stephanie Fuentes Rojas (FIT Lead and EP fellow at Houston Methodist), and Dr. Ingrid Hsiung (Cardiology Fellow at Baylor Scott & White Health) discuss situational assessment of stroke and bleeding risk with expert faculty Dr. Hafiza Khan (Electrophysiologist at Baylor Scott & White Health). In this episode, we discuss stroke and bleeding risk in specific situations such as prior to cardioversion, triggered episodes, and perioperatively. These are scenarios that are commonly encountered and pose specific challenges. Episode notes were drafted by Dr. Stephanie Fuentes. Audio editing by CardioNerds Academy Intern, Dr. Maryam Barkhordarian.

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This series is supported by an educational grant from the Bristol Myers Squibb and Pfizer Alliance. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

We have collaborated with VCU Health to provide CME. Claim free CME here!

Disclosures: Dr. Ellis discloses grant or research support from Boston Scientific, Abbott-St Jude, advisor for Atricure and Medtronic.

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

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How do we choose an imaging modality for excluding LAA thrombus exclusion prior to cardioversion?

What is the data behind the recommendation for uninterrupted AC following cardioversion and what is atrial stunning?

What is the approach of perioperative AC management in patients with atrial fibrillation?

What is the approach to AC in patients with triggered atrial fibrillation?

CardioNerds Amit Goyal, Dr. Colin Blumenthal, Dr. Kelly Arps and Dr. Justice Oranefo discuss mechanical stroke prevention in atrial fibrillation with Dr. Christopher Ellis, cardiac electrophysiology lab director and director of the left atrial appendage closure program at Vanderbilt University. There has been a significant increase in the number of patients undergoing left atrial appendage occlusion (LAAO). This trend is expected to continue with current and upcoming clinical data on this topic. In this episode we dive into the rationale behind LAAO and explore several historical facts. We then proceed to the current state of practice including currently available options, appropriate indications, post op care, and potential complications. Notes were drafted by Dr. Justice Oranefo. Audio editing by CardioNerds Academy Intern, student doctor Chelsea Amo Tweneboah.

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This series is supported by an educational grant from the Bristol Myers Squibb and Pfizer Alliance. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

We have collaborated with VCU Health to provide CME. Claim free CME here!

Disclosures: Dr. Ellis discloses grant or research support from Boston Scientific, Abbott-St Jude, advisor for Atricure and Medtronic.

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

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What are the types of LAAO device?

Left atrial appendage occlusion devices can be divided into epicardial closure and endocardial closure.

Epicardial techniques/devices include surgical ligation, Atriclip, and Lariat. These techniques require pericardial access (either by open thoracotomy or thoracoscopic access). The goals are complete exclusion and ischemic necrosis of the LAA.

LARIAT device

Atriclip device

Endocardial techniques include WATCHMAN FLX and AMULET devices. These techniques require the use of nitinol-based devices which are delivered into the LAA via a transeptal approach. These devices become endothelialized over time resulting in occlusion of the LAA.

AMULET device

WATCHMAN FLX

Who is the ideal candidate for surgical LAAO?

Several studies have evaluated the efficacy of surgical LAA occlusion. The most prominent being the LAOS III trial which randomized 4770 patients with atrial fibrillation and CHA2DS2VASC ≥ 2 undergoing cardiac surgery for other reasons to surgical LAAO vs no LAAO (3,4). The primary outcome of ischemic stroke or systemic embolization occurred in 4.8% of patients in the LAAO group vs 7% of patients in control group over an average follow-up of 3.8 years. Though patients were randomized to LAAO, there was no requirement to stop anticoagulation and this difference was seen despite 75% of patients continuing anticoagulation. Additionally, there was no significant difference in operation time and bleeding complications.

Based on these findings, LAAO should be considered in patients with atrial fibrillation undergoing cardiac surgery for other reasons regardless of the anticipated anticoagulation strategy.

This ability to perform surgical LAAO requires safe access to the pericardial space. For this reason, conditions that create pericardial adhesions (e.g., prior cardiac surgery, chest radiation or trauma, multiple prior ablations) can limit the ability to perform surgical LAAO.

Who is the ideal candidate for endocardial LAAO?

Several  randomized controlled trials and cohort studies have evaluated the utility of both the AMULET and WATCHMAN devices in stroke prevention with the most notable being the PREVAIL, PROTECT AF, and AMULET IDE trials (5,6,7,8,9,10).

Based on the available data, these devices are indicated for stroke prevention in patients with non-valvular atrial fibrillation, a CHA2DS2VASC score ≥ 2 and an appropriate reason to seek a non-drug alternative to anticoagulation therapy. A classic example is a patient with recurrent GI bleeding despite multiple attempts to tolerate anticoagulation. These devices can also be considered in patients with high-risk professions suck as police officers or fire fighters.

Several individual factors also affect the feasibly of endocardial LAAO. A suitable LAA anatomy is necessary for safe device implant (13). Other important considerations are nickel allergy (consider formal allergy testing in patients with suspected nickel allergy), surgical repair of the atrial septum, and severe kyphoscolisis (making adequate transeptal access difficult).

There is no strong data comparing LAAO to DOAC in patients without high bleeding risk, however this question is being studied in 2 ongoing trials, CHAMPION AF (WATCHMAN FLX) and CATALYST (AMULET).

What are the complications of LAAO?

Surgical LAAO is safe and effective when there is complete occlusion of the LAA, however, historically ~ 20-30% are unsuccessful due to incomplete occlusion. More modern surgical techniques including confirmation with intra-operative transesophageal echocardiogram and the Atriclip have demonstrates a higher rate of success. Though the addition of a LAAO has not been shown to add significant time or risk to an already planned cardiac surgery, this requires a patient to already have an indication for surgery and carries the associated risks of that procedure.

Endocardial LAAO has the advantage of being minimally invasive, but procedural complications such as cardiac tamponade, bleeding, and stroke can occur. More recent data has shown a < 1% procedural risk with the WATCHMAN FLX device. Other post procedural complications of endocardial LAAO devices include peridevice leak (~ 10% incidence; leaks ≥ 3mm are associated with an increased risk of stroke) and device related thrombus (DRT; 2-3% incidence). Device embolism is rare but carries potentially devastating consequences (12).

What is the anticipated post operative care following LAAO?

Post operative care with surgical LAAO is predominently dictated by the primary indication for surgery. Due to the high incidence incomplete exclusion, an intra or post-operative TEE is necessary to document complete LAA occlusion. As for anticoagulation, there is no current randomized control trial data that supports using surgical LAAO as an alternative to AC. As previously discussed, a lower incidence of stroke was seen in the LAOS III trial, but this trial specifically studied using surgical LAAO as an adjunct to OAC, not as a replacement.

With endocardial LAAO, appropriate patient and device selection as well as adequate post-operative care is crucial to maximize safety and efficacy. Patients must be able to tolerate some degree of short-term anticoagulation with the goal to safely transition to single anti-platelet therapy while minimizing the risk of stroke and bleeding. This involves OAC for at least 45 days followed by aspirin monotherapy if no DRT or peridevice leak is seen on post-op imaging. DAPT (aspirin and clopidogrel) can be used instead of OAC in the early phase however there is not strong data for this strategy (11). Post-op imaging (TEE or CTA) is required approximately ~45 days, 6 months, and 1 year after the procedure.

In patients who have undergone LAAO, LAA imaging is recommended prior to cardioversion, however, in the absence of DRT or device leaks anticoagulation is not necessary post cardioversion (14,15).

The field of Cardiovascular Genomics has advanced tremendously over the past two decades, having a significant clinical impact and changing the perception of the role and scope of genetic testing in several cardiovascular domains.  To kickstart the Cardiovascular Genomics series, CardioNerds Dr. Sara Coles (FIT at Duke University), Dr. Colin Blumenthal (CardioNerds Academy faculty and FIT at UPenn), and Dr. Karla Asturias (CardioNerds Academy fellow and medicine resident at Pennsylvania Hospital) have a great discussion with Dr. James Daubert, a clinical electrophysiologist at Duke University, with a particular interest in inherited arrhythmia syndromes and sports cardiology. In this episode, we review basic concepts of cardiovascular genomics and genetics in electrophysiology while discussing when to (and when not to!) test our patients and their families and how to approach those results. Audio editing by CardioNerds academy intern, Pace Wetstein.

This episode was developed in collaboration with the American Society of Preventive Cardiology and is supported with unrestricted educational funds from Illumina, Inc. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

This CardioNerds Cardiovascular Genomics series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs.

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

Pearls • Notes • References

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Notes were developed by Dr. Karla Asturias:

What are some key basic concepts in clinical genetics?

How do we classify genetic testing results according to the American College of Medical Genetics and Genomics (ACMG) guidelines?

What types of genetic testing are available, and when do we use them?3

What is the role of genetic testing in the management of inherited cardiovascular diseases? 9

How do we approach patients with a confirmed or suspected diagnosis of an inherited cardiovascular disease? 1,3

Supplementary bibliography:

It’s another session of CardioNerds Rounds! In these rounds, Dr. Stephanie Fuentes (EP FIT at Houston Methodist) joins Dr. Hugh Calkins (Professor of Medicine and Director of the Electrophysiology Laboratory and Arrhythmia Service at Johns Hopkins Hospital) to discuss the nuances of atrial fibrillation (AF) management through challenging cases. As an author of several guideline and expert consensus statements in the management of AF and renowned clinician, educator, and researcher, Dr. Calkins gives us many pearls on the management of AF, so don’t miss these #CardsRounds! 

This episode is supported with unrestricted funding from Zoll LifeVest. A special thank you to Mitzy Applegate and Ivan Chevere for their production skills that help make CardioNerds Rounds such an amazing success. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds. Case details are altered to protect patient health information. CardioNerds Rounds is co-chaired by Dr. Karan Desai and Dr. Natalie Stokes. 

Speaker disclosures: None

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Case #1 Synopsis:

A woman in her mid-60s presents with symptomatic paroxysmal atrial fibrillation (AF). An echocardiogram has demonstrated that she has a structurally normal heart. Her primary care doctor had started Metoprolol 50 mg twice a day but she has remained symptomatic. In office, an EKG confirms AF, but she converts to sinus while there. She is seeking advice to prevent further episodes and in general wants to avoid additional medications

Case #2 Takeaways

1. We discussed several potential options for treatment. Amongst the first things we discussed was amiodarone. In a patient of this nature without structural heart disease and under the age of 70, Dr. Calkins discussed that he would probably consider amiodarone as a 2nd line option. While amiodarone may be effective in maintaining sinus rhythm in comparison to other antiarrhythmic medications like sotalol, flecainide, and propafenone, it does have significant toxicity.
2. If antiarrhythmic drugs (AAD) were to be considered, we also discussed the options of dofetilide versus sotalol. Dofetilide typically requires inpatient initiation due to the risk of QT
    prolongation and Torsades. Since women tend to have longer corrected QT (QTc) intervals, high dose dofetilide may be more proarrhythmogenic in women. Though, Dr. Calkins noted that many patients don’t tolerate sotalol due to fatigue and generally dofetilide is well tolerated.
3. When it comes to the “pill in the pocket” approach, Dr. Calkins noted that its utility is more so in patients with persistent AF that is known to not stop on its own. For instance, an individual who has AF a few times a year that is persistent may benefit from flecainide or propafenone (“in the pocket”) instead of being brought in for an electrical cardioversion. In this scenario, the first time one of these agents is used, the patient ought to be closely monitored. For our patient, her episodes were too frequent and self-terminating for a “pill in the pocket” approach to be effective.
4. Current guideline recommendations for catheter ablation include a Class IA recommendation for patients with paroxysmal AF refractory to AADs, and a Class IIA recommendation as first-line therapy for patients with paroxysmal AF.
5. In the 2020 ESC Atrial Fibrillation Guidelines, catheter ablation is given a Class IA recommendation to improve symptoms of AF recurrences in patients who have failed or are intolerant of one Class I or III AADs. For patients who have failed or have been intolerant of beta blocker alone for rhythm control, catheter ablation is given a Class IIA recommendation. As first-line therapy in paroxysmal AF, catheter ablation is given a Class IIA recommendation as well.
6. Of note, three recent trials have demonstrated catheter ablation as first line therapy is reasonable and newer guidelines will reflect this. Specifically, EARLY-AF compared ablation (cryoablation) vs AAD (mainly with flecainide/propafenone) as a first line therapy. The cryoablation arm showed significantly less recurrence of AF at one year
   • The guidelines clearly state that aligning the treatment plan with the patient’s goals and risk tolerance are paramount. Catheter ablation does have potential complications such as pericardial effusion or access-related issues, though these are rare. Furthermore, as time has passed, catheter ablation success rates have improved.
   • Up and coming techniques such as electroporation may be game-changing with regards to success rate and safety. Waiting times for a procedure may be an issue, so one could consider an AAD, such as flecainide, as a standing dose awaiting the procedure.
7. Regarding predictors of success for catheter ablation, Dr. Calkins noted that the key factor was type of AF. With paroxysmal AF there is roughly 70-80% success rate with the 1st procedure, 50-70% with persistent AF, and 30-50% with longstanding persistent AF. Other predictors of success include BMI (higher BMI associated with a lower success rate and a higher rate of complications), left atrial size (with a linear dimension of ≥ 5.5 cm indicating less likelihood of success), age, and obstructive sleep apnea.
8. One of the questions that was raised was screening for structural heart disease before starting flecainide/propafenone. Typically, an EKG and TTE are done, and if they are not suggestive of structural heart disease, Dr. Calkins noted it would be reasonable to use these agents. With increasing age, there’s increased risk of subclinical CAD, though it is not in the guidelines to perform functional testing or anatomic imaging prior to starting these agents.
9. Finally, Dr. Calkins noted as an aside that in patients with sick sinus syndrome, management in the past has involved placing a permanent pacemaker (PPM) followed by AAD agents. However, catheter ablation may be a better option because it treats AF and improves the sinus rate because of its effect on the autonomic system, eliminating pauses that would have otherwise warranted a pacemaker. After ablation, the resting HR can improve 10-30 bpm and this can be a marker of successful catheter ablation.

Case #2 Synopsis:

A man in his mid-60s with a history of surgically placed bioprosthetic AVR, CAD with prior CABG, newly diagnosed ischemic cardiomyopathy with LVEF 20-25% with imaging revealing reversible ischemia in multiple coronary territories, presented to the clinic with dyspnea in the setting of persistent AF now 6 weeks after multi-vessel PCI. Other relevant information is that he appears congested in clinic and his EKG demonstrates a left bundle branck block (LBBB) with QRS at 172 ms. He seeks your opinion for management options.

Case #2 Takeaways

1. Dr. Calkins discussed that the only safe AAD in this circumstance would be Amiodarone, and that the risk of developing complete heart block (CHB) in a patient with LBBB placed on amiodarone is not high enough to preclude its use. One strategy would be to give this patient an amiodarone load followed by direct current cardioversion (DCCV). Following DCCV, if the patient maintains sinus rhythm, one could consider continuing with amiodarone at a lower dose or pursuing catheter ablation as a next strategy.
2. Dr. Calkins emphasized understanding the temporal relationship between AF and HF in patients with reduced ejection fraction. In patients with new-onset AF and reduced EF, aggressive rhythm control with catheter ablation would be warranted because there is a higher likelihood of improving the cardiomyopathy.
3. Another option to consider in patients with HFrEF and permanent atrial fibrillation that remain symptomatic or who have had hospitalizations with HF is AV node ablation with cardiac resynchronization therapy, though for a patient like this other viable treatment options remain to be tested. Regarding an ICD, the patient may recover their EF post-revascularization and implementation of guideline-directed therapy. Thus, with ischemic cardiomyopathy post revascularization, the decision to place an ICD should wait 90 days. Furthermore, the EF may improve with control of the AF.

Case #3 Synopsis:

A woman in her mid-80s with hypertension and recent COVID-19 pneumonia is admitted to the hospital with hypoxia, reduced LVEF and found to have AF with rapid ventricular response. The patient’s underlying conditions were treated and attempts at ventricular rate control were attempted but limited by blood pressure. A DCCV with amiodarone loading was also attempted but failed to maintain sinus rhythm. 

Case #3 Takeaways

1. Some feasible options in this circumstance include further loading with amiodarone and reconsidering another DCCV versus an AV node ablation with permanent pacemaker implantation if medical therapies are limited or failing.
2. Digoxin use for rate control alone in critically ill patients is typically discouraged. This is because we now know that its mechanism of action involves raising vagal tone and acutely ill patients typically have low vagal tone so it may not be helpful. However, in patients with rapid AF and HF, it is reasonable to use it. When used in combination with amiodarone, one may reduce the dose of digoxin in half given its drug-drug interaction

CardioNerds (Amit Goyal), Dr. Colin Blumenthal (CardioNerds Academy House Faculty Leader and FIT at the University of Pennsylvania), and Dr. Anjali Wagle (CardioNerds Ambassador and FIT at Johns Hopkins University), discuss the baseline assessment of stroke and bleeding risk in patients with atrial fibrillation (AF) with Dr. Elaine Hylek. Dr. Hylek is a professor of medicine at the Boston University School of Medicine and is the Director of the Thrombosis and Anticoagulation Service at Boston Medical Center. Stroke is a potentially devastating and preventable complication of AF. Understanding the balance between stroke and bleeding risk is crucial in determining who should be on anticoagulation. Join us to discuss this topic! In the next episode of the series, we will discuss situational risk assessment in the context of peri-cardioversion, peri-procedural status, triggered atrial fibrillation, and more. Audio editing by CardioNerds Academy Intern, Pace Wetstein.

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This series is supported by an educational grant from the Bristol Myers Squibb and Pfizer Alliance. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

We have collaborated with VCU Health to provide CME. Claim free CME here!

Disclosures: Dr. Hylek discloses grant and research support from Medtronic and Janssen, and honoraria and/or consulting fees from Boehringer Ingelheim, and Bayer.

Enjoy this Circulation 2022 Paths to Discovery article to learn about the CardioNerds story, mission, and values.

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Notes drafted by Dr. Anjali Wagle

1. Why do strokes happen in atrial fibrillation? Why is reducing stroke risk so important?

Atrial fibrillation is associated with a significantly increased risk of stroke. The mortality of strokes related to AF have been estimated to be around 25% at 30 days in early studies which included either persistent or permanent AF, though of note, these studied were biased towards larger strokes since the diagnosis was based on physical exam and not high resolution imaging.

AF promotes thrombogenesis through Virchow’s triad which includes:

In atrial fibrillation, patients usually have a dilated left atrium and decreased blood flow through the atrial appendage which contribute to thrombogenesis.

Multiple risk scores have been derived (i.e., CHA2DS2VASc) for estimation of stroke risk in patient with AF to identify whom to treat with anticoagulation to reduce the stroke risk.

2. How were CHADS2 and CHA2DS2VASc (CV) created and validated?

The CHADS2 score was derived in 2001 by Gage et al from data including hospitalized patients with nonrheumatic AF who were not prescribed warfarin at hospitalized discharge. The CHADS2 score assigns one point to congestive heart failure, hypertension, age ≥ 75 years, and diabetes mellitus and two points to a previous history of stroke or transient ischemic attack (TIA) for a total of 6 points. Stroke rate per 100 patient-years rose by a factor of 1.5 for each 1-point increase in the CHADS2 score.

However, it was found that there were several limitations associated with the CHADS2 score including that more than half of the patients were classified as moderate risk, making it unclear if antiplatelet or anticoagulation should be used in this population. Additionally, there were other “minor” risk factors (female sex, CAD, age 65-74) that were not included in the score.

In 2010, Lip et al proposed the CHA2DS2VASc score that included these three additional factors: female gender, vascular events, and age 65-74. These additions to the original CHADS2 score allowed the CHA2DS2VASc score to reclassify patients in the moderate risk group into either the high or low risk groups (CV <1 or >2), making the decision of when to start anticoagulation easier.

Some weaknesses of the CV score include that the individual factors are binary. For example, one point for diabetes does not discriminate risk based on if the patient’s A1c is 14 vs. 7. Similarly, the score is static and assumes the risk from each risk factor doesn’t change over time even though the endothelial dysfunction caused by a specific disease state isn’t fixed. Additionally, the C-statistic for the CV score is only 0.6 with newer scores that are more accurate including such as GARFIELD-AF (but these newer scores are less user friendly). That being said, the score still does a very good job of differentiating between high and low risk patients, which is the most important clinical question when deciding if someone needs anticoagulation.

3. Which populations were not studied in the validation of the CV score?

Many of these studies have woefully low enrollment of racially diverse populations. Additionally, patients with amyloidosis, moderate-severe MS, and HOCM have a baseline higher risk of stroke were excluded from these studies. Patients with bioprosthetic valves were also excluded from the original derivation though there is now limited data showing use of the CV is reasonable.

4. How does AF burden affect stroke risk? Is there a temporal association between AF and stroke?

Early trials did not find a temporal association between AF and stroke, though these trials often used physical exam definitions for stroke and current technology like implantable loop recorders (ILRs) didn’t exist to monitor 24/7. More modern studies like the TREND and KP-RHYTHM trials showed that stroke risk is related to AF burden. Longer episodes of AF seem to clearly be associated with stroke, but shorter episodes of AF aren’t as temporally related to stroke. In the LOOP trial use of ILRs to detect episodes of AF longer than 6 minutes led to a 3-fold increase in AF detection and initiation of AF, but did not reduce the number of strokes. This could indicate that there is some amount of AF that doesn’t require AC or that short runs of AF are associated with atrial myopathy that could be causing the strokes. It remains unclear what is the “chicken and egg” in this scenario.

5. How can we assess bleeding risk for patients with atrial fibrillation? How can we use these scores in our clinical practice?

Developed and published in 2010 by Pisters et al., the HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile INR, elderly [age >65], medication predisposing to bleeding, excessive alcohol use) score aimed to create an easy to calculate and clinically meaningful score to estimate bleeding risk. It was validated using 3,978 patients from the Euro Heart Survey on AF and had good predictive accuracy (C-statistic 0.72). Of note, the score uses the less severe ISTH definition for a major hemorrhage, which doesn’t require as severe bleeding as the TIMI major bleeding definition.

Many of the factors that go into the score are dynamic (for example HTN is SBP > 160 and not a history of HTN). The intention was to alert the provider of potentially modifiable factors that could be addressed to lower bleeding risk (such as better BP control). This would reduce the patients HAS-BLED score and therefore their bleeding risk. There is no absolute cutoff where anticoagulation in AF would be considered prohibitive.

6. What is the approach for patients with borderline stroke risk with a CV of 1 in men or 2 in women?

Patients with a CV of 1 have between a 0.6% and a 0.9% risk of stroke/TIA/systemic embolism in a given year. That means even with a CV of 1 they have close to a 1/100 risk of an event in a given year. Given the high mortality and morbidity with embolic strokes and the lower incidence of major bleeding with modern DOACs, should have shared decision-making conversation with patients about starting AC at this risk level. One can consider other risk factors not in CV like LA function, appendage morphology, AF burden etc to help as tie breakers.

CardioNerds (Dr. Kelly Arps, Dr. Colin Blumenthal, Dr. Dan Ambinder, and Dr. Teodora Donisan) discuss the screening, detection, and diagnosis of atrial fibrillation (AF) with Dr. Ben Freedman. AF is frequently undiagnosed and its first manifestation can be a debilitating stroke. European and American guidelines differ slightly with regards to guidelines for AF screening in asymptomatic individuals. There are multiple methods available to screen for AF; the setting and the clinical scenario can help guide the choice. Consumer-led screening has its own challenges, as it can detect AF in a younger population where we should prioritize aggressive management of risk factors and comorbidities. There is uncertainty regarding the minimum AF burden that increases thromboembolic risk, however a high CHAD2S2-VASc score remains the strongest predictor of stroke risk independent of AF burden. Perioperative AF associated with non-cardiac surgery has increased risk of future stroke and adverse cardiac outcomes and should likely be treated as a new diagnosis of chronic AF.   

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This series is supported by an educational grant from the Bristol Myers Squibb and Pfizer Alliance. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

We have collaborated with VCU Health to provide CME. Claim free CME here!

Disclosures: Dr. Ben Freedman disclosed that he has received grant or research support from Pfizer.

Pearls • Notes • References • Guest Profiles • Production Team

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1. “Stroke is a poor early sign of AF.”  
   1. AF remains frequently undiagnosed and there remains uncertainty about the optimal target population and screening methodology.  
2. “We have to tailor AF screening to the purpose we’re using it for”  
   1. If in a primary care setting, check the pulse. If the goal is to exclude high-risk AF –  handheld ECG for heart rhythm snapshots are appropriate. If the goal is to identify or exclude AF with a high level of certainty, continuous monitors are necessary for greater sensitivity. 
3. Consumer-led screening is performed by (mostly young) individuals using commercial monitors and smart watches, facilitating earlier recognition of paroxysmal AF in this population. In these cases, we should prioritize aggressive management of risk factors and comorbidities to reduce the risk of progression to persistent AF. 
4. There is no specific cutoff for AF duration which has been identified to predict elevated stroke risk; AF is likely both a risk factor and a risk marker for stroke, suggesting an underlying atrial myopathy. 
5. Non-cardiac surgeries and procedures can be considered “AF stress tests.” If AF occurs in these settings, it is usually more clinically significant and has a higher risk of stroke and death than AF associated with cardiac surgeries. 

Notes drafted by Dr. Teodora Donisan and reviewed by Dr. Kelly Arps

1. Why is it important to screen for AF and who should be screened? 

AF is frequently undiagnosed and its first manifestation can be a debilitating stroke or death. Let’s go over a few numbers: 

• 15% of people with AF are currently undiagnosed and 75% of those individuals would be eligible for anticoagulation.1   
• 10-38% of individuals with ischemic strokes are found to have AF as a plausible cause, and the true proportion may be even higher, given difficulties in detecting intermittent AF.2 

Current guideline recommendations:  

• European guidelines: opportunistic screening for AF is recommended for individuals ≥65 years old.3 

• American guidelines: AF screening is recommended in patients with cryptogenic strokes and those with device-recorded atrial high-rate episodes.4 

Opportunistic screening for AF can be done by checking the pulse or noticing the irregular heart rate on blood pressure monitors. When AF is found by opportunistic screening at a single time point, it is usually persistent AF. Continuous ambulatory heart rhythm monitoring can identify shorter episodes of paroxysmal AF, perhaps earlier in the AF disease course.  

In patients with unexplained stroke we have different ways to search for occult AF: 

• In the hospital: all patients should have 72h of ECG monitoring. There is evidence that nurse-led ECG surveillance detects more paroxysmal AF earlier and more frequently than 24-hour Holter recordings.5  
• After discharge: if clinical suspicion for occult AF is high (e.g., cerebral imaging concerning for cardioembolic source, evidence of left atrial enlargement, elevated BNP), consider more prolonged monitoring via cutaneous patches, multiple Holter recordings, or implantable cardiac monitors. 

2. What tools are currently available to screen for AF? 

There are multiple tools available for AF screening: pulse palpation, oscillometry, and ambulatory heart rhythm ECG monitoring with external or subcutaneous devices. Handheld ECG devices are very convenient options, as they can diagnose AF in 30 seconds directly, whereas other methods such as oscillometry would ultimately require ECG confirmation. 

• If in the office for a quick screen: check the pulse; 
• If you’re looking for high-burden AF: handheld one-time ECG; 
• If you’re looking to identify or rule out AF with a high degree of certainty: continuous monitoring with transcutaneous patch or implantable monitor. 

3. How should commercial monitor/smart watch data be incorporated into clinical practice? 

We need to be aware of the population who have access to and more often use these modern technologies; use is unequally distributed around the world and across the age span.6 These devices are most often used by people who are 35-40 years old, not the typical population for whom AF screening may be more impactful. If we do identify AF in these younger individuals, starting anticoagulation may not be indicated. It is important, however, to emphasize more aggressive management of risk factors and comorbidities (e.g., weight loss, diet, exercise, alcohol reduction, hypertension control, screening for and treating prediabetes and diabetes, screening for obstructive sleep apnea, and assessing thyroid function) to reduce the risk of AF progression. 

4. How much atrial fibrillation is clinically relevant? 

There is uncertainty regarding the minimum AF burden that increases the thromboembolic risk above an individual’s baseline risk, with studies exploring durations of ≥ 5 minutes to ≥ 24 hours.7,8 Several studies show that there isn’t a clear temporal relationship between device-detected high-rate episodes and strokes either, with only a small number of patients experiencing arrhythmia in the month before a stroke.9 

• The CHA2DS2-VASc score is very important when discussing thromboembolic risk: if it is low, then the risk of stroke is low; if it is high, risk of stroke is higher, even if there is a low burden of AF. 
• AF is likely both a risk factor and a risk marker for stroke, suggesting an underlying atrial myopathy. This would explain why a specific cutoff point for AF duration is not necessarily relevant to predict stroke risk. 

5. How should clinicians approach peri-operative AF? 

Perioperative AF is associated with increased perioperative morbidity, higher stroke rates, more readmissions, and lower survival.10 The significance of AF is different depending on the type of surgery: 

• With AF after cardiac surgery (which involves opening the pericardium and direct irritation of the atria), the incidence of perioperative AF is greater (20-30%). Roughly 25% of patients with AF after CABG experience asymptomatic recurrent AF episodes during the first month after the procedure.11 Many individuals with AF after cardiac surgery do not go on to have chronic AF. 
• With AF after general surgery, the chance of chronic AF and future risk of adverse events are significantly elevated, as AF should not be a direct result of the procedure itself and instead likely represents a previously undiagnosed atrial myopathy. Consider noncardiac procedures as an “AF stress test”.   

Give this information, we should strongly consider anticoagulation after identifying AF associated with non-cardiac surgeries or procedures, when indicated by the CHA2DS2-VASc score. We should start anticoagulation in individuals with AF associated with cardiac surgeries only if there are other risk factors or clini

Opportunistic screening for AF can be done by checking the pulse or noticing the irregular heart rate on blood pressure monitors. When AF is found by opportunistic screening at a single time point, it is usually persistent AF. Continuous ambulatory heart rhythm monitoring can identify shorter episodes of paroxysmal AF, perhaps earlier in the AF disease course.  

In patients with unexplained stroke we have different ways to search for occult AF: 

• In the hospital: all patients should have 72h of ECG monitoring. There is evidence that nurse-led ECG surveillance detects more paroxysmal AF earlier and more frequently than 24-hour Holter recordings.5  
• After discharge: if clinical suspicion for occult AF is high (e.g., cerebral imaging concerning for cardioembolic source, evidence of left atrial enlargement, elevated BNP), consider more prolonged monitoring via cutaneous patches, multiple Holter recordings, or implantable cardiac monitors.  

1. Turakhia MP, Shafrin J, Bognar K, et al. Estimated prevalence of undiagnosed atrial fibrillation in the United States. PLoS One. 2018;13(4):e0195088. 

2. Friberg L, Rosenqvist M, Lindgren A, Terént A, Norrving B, Asplund K. High prevalence of atrial fibrillation among patients with ischemic stroke. Stroke. 2014;45(9):2599-2605. 

3. Hindricks G, Potpara T, Dagres N, et al. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS): The Task Force for the diagnosis and management of atrial fibrillation of the European Society of Cardiology (ESC) Developed with the special contribution of the European Heart Rhythm Association (EHRA) of the ESC. Eur Heart J. 2021;42(5):373-498. 

4. January CT, Wann LS, Calkins H, 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. J Am Coll Cardiol. 2019;74(1):104-132. 

5. Yan B, Tu H, Lam C, et al. Nurse Led Smartphone Electrographic Monitoring for Atrial Fibrillation after Ischemic Stroke: SPOT-AF. J Stroke. 2020;22(3):387-395. 

6. Turakhia MP, Desai M, Hedlin H, et al. Rationale and design of a large-scale, app-based study to identify cardiac arrhythmias using a smartwatch: The Apple Heart Study. Am Heart J. 2019;207:66-75. 

7. Glotzer TV, Hellkamp AS, Zimmerman J, et al. Atrial high rate episodes detected by pacemaker diagnostics predict death and stroke: report of the Atrial Diagnostics Ancillary Study of the MOde Selection Trial (MOST). Circulation. 2003;107(12):1614-1619. 

8. Healey JS, Connolly SJ, Gold MR, et al. Subclinical atrial fibrillation and the risk of stroke. N Engl J Med. 2012;366(2):120-129. 

9. Freedman B, Camm J, Calkins H, et al. Screening for Atrial Fibrillation: A Report of the AF-SCREEN International Collaboration. Circulation. 2017;135(19):1851-1867. 

10. Bianco V, Kilic A, Yousef S, et al. The long-term impact of postoperative atrial fibrillation after cardiac surgery. J Thorac Cardiovasc Surg. 2022. 

11. Ha ACT, Verma S, Mazer CD, et al. Effect of Continuous Electrocardiogram Monitoring on Detection of Undiagnosed Atrial Fibrillation After Hospitalization for Cardiac Surgery: A Randomized Clinical Trial. JAMA Netw Open. 2021;4(8):e2121867. 

Dr. Ben Freedman serves as Director of External Affairs at the Heart Research Institute and Leader of its Heart Rhythm and Stroke Prevention Group, Honorary Professor of Cardiology at The University of Sydney, Charles Perkins Centre. He formed the AF-SCREEN International Collaboration in 2015, which now has over 190 members from 38 countries, including some of the most prolific names in AF research. In 2011 he was awarded the Order of Australia Medal for service to medicine as a clinician, educator, and researcher.

Teodora Donisan @TDonisan is an internal medicine resident at Beaumont Hospital and rising cardiology fellow at Mayo Clinic. She completed medical school at the Carol Davila University of Medicine and Pharmacy, in her home country of Romania. After medical school, she worked as cardiology resident in Bucharest for 2 years, followed by a research rotation in interventional cardio-oncology at The University of Texas MD Anderson Cancer Center. Teo is passionate about medical education and loves the rush of the cardiac intensive care unit. She dreams of photographing wildlife in all National Parks in the United States.

Atrial fibrillation may reach pandemic proportions in the next 2-3 decades. Factors that drive this phenomenon have been studied in predominantly White populations, leading to a significant underrepresentation of certain racial/ethnic groups in atrial fibrillation epidemiological studies. Most atrial fibrillation epidemiology studies suggest that the non-Hispanic Black population has a lower incidence/prevalence of atrial fibrillation, despite a higher risk factor burden (“Afib paradox”). At the same time, non-Hispanic Blacks have worse outcomes compared to the White population and underrepresented populations and women are less likely than White men to receive optimal guideline-based therapies for atrial fibrillation.

In this episode, CardioNerds Dr. Kelly Arps (Co-Chair Atrial Fibrillation series, Cardiology fellow at Duke University), Dr. Colin Blumenthal (Co-Chair Atrial Fibrillation series, CardioNerds Academy House Faculty Leader for House Jones, Cardiology fellow at the University of Pennsylvania), and Dr. Dinu-Valentin Balanescu (CardioNerds Academy Faculty for House Jones, rising internal medicine chief resident at Beaumont Hospital), discuss with Dr. Larry Jackson (cardiac electrophysiologist and Vice Chief of Diversity, Equity, and Inclusion in the Division of Cardiology at Duke University) about atrial fibrillation epidemiology and health equity, challenges and possible solutions to improving diversity in clinical trials, and race/ethnicity/sex/gender differences in the detection, management, and outcomes of atrial fibrillation. Audio editing by CardioNerds Academy Intern, student doctor Akiva Rosenzveig.

This CardioNerds Atrial Fibrillation series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Kelly Arps and Dr. Colin Blumenthal.

This series is supported by an educational grant from the Bristol Myers Squibb and Pfizer Alliance. All CardioNerds content is planned, produced, and reviewed solely by CardioNerds.

We have collaborated with VCU Health to provide CME. Claim free CME here!

Disclosure: Larry R. Jackson II, MD, MHs, has the following relevant financial relationships:
Advisor or consultant for: Biosense Webster Inc.
Speaker or a member of a speakers bureau for: Biotronik Inc.; Medtronic Inc.

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1. Atrial fibrillation confers an enormous public health burden. It is estimated that it will reach pandemic proportions over the next 30 years, with potentially 100-180 million people worldwide suffering from this condition.
2. Large epidemiological atrial fibrillation registries have very small populations of underrepresented groups. More diverse enrollment in clinical trials is essential and may be obtained by increasing diversity among research staff, principal investigators, and steering committees, and use of mobile/telehealth technologies to remove bias related to differences in presentation. The CardioNerds Clinical Trials Network specifically aims pair equitable trial enrollment with trainee personal and professional development.
3. Most atrial fibrillation epidemiology studies suggest that the non-Hispanic Black population has lower incidence/prevalence of atrial fibrillation, despite higher risk factor burden. This “paradox” is likely due to a multifactorial process, with clinical differences, socioeconomic factors, and genetic factors contributing.
4. Underrepresented populations are less likely than White patients to receive optimal guideline-based management of atrial fibrillation. Though there is a higher incidence of intracranial bleeding on vitamin K antagonists in this population, they are less likely to receive optimal anticoagulation for stroke prevention with direct oral anticoagulants. Also, despite overall worse outcomes, they are less likely to be prescribed rhythm control strategies or offered catheter-based ablation despite known data with improved outcomes with early rhythm control.
5. Gender-based differences in atrial fibrillation epidemiology, management, and outcomes also exist. Compared to men, women have a lower incidence/prevalence of atrial fibrillation but are more likely to be symptomatic. They are also more likely to receive rate instead of rhythm control strategies and suboptimal stroke reduction therapies Overall, women have worse outcomes than men. 

“I want to differentiate [equitable care] from equal care. I think this idea of equity means that we have to take into account the myriad of differences that we see between people of different races, ethnicities, genders, sexes, regions, whether they’re citizens or not, whether they’re disabled or not […] and make sure that we’re thinking about those in terms of prescriptions and discussion and communication, and offering our patients therapy, […] it’s not [enough] to offer different people the same therapy because they may have different barriers that may prevent them from uptaking that therapy or utilizing that.”

Drafted by Dr. Dinu-Valentin Balanescu and reviewed by Dr. Colin Blumenthal.

1. What factors contribute to the atrial fibrillation epidemic and where do we expect to be over the next 20-30 years?

• The current global prevalence of atrial fibrillation is unclear. It is estimated that over the next 30 years, the prevalence of atrial fibrillation may reach pandemic proportions, with potentially 100-180 million people worldwide suffering from this condition.1
• Factors that drive this increase:
  • Classic: heart failure, coronary artery disease, hypertension, diabetes, tobacco use, obesity.
  • Novel risk factors: obstructive sleep apnea, metabolic syndrome, left ventricular hypertrophy, left atrial enlargement.
  • Novel markers (inflammatory, biochemical): B-type natriuretic peptide, CRP.
• Many of the above factors have been determined by studying predominantly White populations.

2. There is conflicting data regarding the incidence of atrial fibrillation across race and ethnicity, with most studies suggesting a higher incidence in the non-Hispanic White population compared to non-Hispanic Black or Hispanic individuals, while some suggest a similar prevalence. How is this discrepancy explained?

• The discrepancy may stem from various rates of clinical detection, rather than incidence or prevalence, of atrial fibrillation between different race/ethnicity groups (“ascertainment bias”).
• Conflicting data persists even when detection is adjusted for. A cohort of the MESA study showed that the prevalence among race and ethnicity was similar when the diagnosis was made using Holter monitor data.2 Data from the ASSERT trial suggest that when using implantable loop recorders, the incidence of atrial fibrillation among the non-Hispanic Black population was lower than a European White population.3
• There is a substantial need for further study on the epidemiology of atrial fibrillation across race/ethnicity.

3. Non-Hispanic Black populations have a higher risk factor burden for atrial fibrillation than White patients, but as described above most studies demonstrate a lower incidence – how is this “paradox” explained?

• The “atrial fibrillation paradox” is a double paradox, as Dr. Jackson explains: despite a higher risk factor burden, non-Hispanic Blacks have a lower incidence/prevalence of atrial fibrillation. At the same time, non-Hispanic blacks have worse outcomes compared to the white population.4
• This is likely due to a multifactorial process, with clinical differences, socioeconomic factors, and genetic factors contributing.5 Specifically:
  • Ascertainment bias. Certain racial/ethnic groups may have access issues preventing them from seeking medical attention for rhythm assessment and/or may be less likely to be prescribed rhythm monitors for objective assessment. Additionally, it has been shown that the non-Hispanic Black population has more paroxysmal symptoms, which could lead to difficulties in diagnosis.
  • Survival bias. Non-Hispanic Whites have a longer life expectancy compared to underrepresented racial/ethnic groups, which may lead to a greater risk of developing atrial fibrillation over time.
  • Genetic/epigenetic differences. Stronger European ancestry within non-Hispanic Blacks is associated with a higher risk of atrial fibrillation. Genome-wide association studies suggest that non-Hispanic Blacks may have protective genes compared to whites.

4. What are barriers to the diagnosis of atrial fibrillation in understudied populations and how can inclusion in research studies be improved?

• Large epidemiological registries have traditionally included very small proportions of underrepresented groups. A more diverse enrollment in clinical trials is essential.
• Clinical trial participation of marginalized populations may be achieved by:
  • Using mobile/telehealth technologies to recruit and follow patients.
  • Increasing diversity and heterogeneity among research staff, principal investigators, steering committees, which has been shown to improve study diversity.
• From a clinical standpoint, barriers may be removed by:
  • Educating patients on atrial fibrillation, its complications, its treatments, and its outcomes.
  • Involving family and other social communities as part of decision-making support.

• The CardioNerds Clinical Trials Network specifically aims pair equitable trial enrollment with trainee personal and professional development

5. How are race and ethnicity associated with the workup for atrial fibrillation and the use of specialized diagnostic equipment?

• Clinicians should have a high index of suspicion for atrial fibrillation while understanding the racial/ethnic/gender differences in presentation and management.
• Patients from various racial/ethnic/gender groups may present with different symptoms of atrial fibrillation. For example, non-Hispanic Blacks are more likely to be more symptomatic, but also more paroxysmal. They are also more likely to have a have lower quality of life.6
• If clinical index of suspicion is high, ambulatory monitoring should be pursued.

6. What are the differences in management between White and black patients when it comes to rate versus rhythm control, anticoagulation, and procedures?

• With regards to anticoagulation:
  • Black patients are less likely than white patients to be prescribed anticoagulation or, if prescribed, are significantly less likely to be prescribed a direct oral anticoagulant (DOAC).7
  • Underrepresented populations have a higher risk of intracranial hemorrhage while on a vitamin K antagonists (VKA) compared to whites. DOACs overall have a lower risk of intracranial hemorrhage and should preferentially be prescribed over VKAs.8
  • Pivotal trials comparing DOACs to VKAs have had a very low enrollment of Hispanic and non-Hispanic black populations, so it is possible the benefit is even greater in this population.
• With regards to rhythm control strategies:
  • Black patients are less likely to receive rhythm control therapies (whether cardioversion, medical, or invasive) and more likely to receive rate control therapy.8
  • Black patients have a better response to catheter ablation of atrial fibrillation compared to white patients. This treatment may be preferred in underrepresented populations to improve outcomes compared to medical therapy alone.9

7. What are gender-based differences in AF epidemiology and management and are there underlying differences in the electrical conduction system between men and women that affect management decisions?

• Compared to men, women:
  • Have a lower incidence and prevalence of atrial fibrillation.
  • Are more likely to be symptomatic.
  • Are more likely to receive rate control strategies as opposed to rhythm control strategies.
  • Are less likely to receive stroke reduction therapies (e.g., anticoagulation or left atrial appendage closure).
  • Have worse outcomes: higher risk of stroke, QTc prolongation and torsades de pointes, heart failure, and mortality.10,11
• These differences may be due to:
  • Autonomic differences (especially in the 2nd-5th decades of life).
  • Differences in the effects of sex hormones. Estrogen can affect the differential expression of ion channel subunits, ion channel function, inhibits the hERG K channel. Certain sex hormones may also impact action potential duration and alter calcium metabolism.

8. Are the differences in the diagnosis, work-up, and treatment of atrial fibrillation among racial/ethnic/gender groups associated with differences in outcomes?

• Underrepresented groups have worse outcomes compared to the White population: higher risk of stroke, heart failure, and mortality.12
• Differences in the management of atrial fibrillation among racial/ethnic/gender groups contribute to these worse outcomes, e.g., lower rates of stroke prevention therapies and rhythm control strategies (patients in sinus rhythm had a 50% reduction in mortality in the AFFIRM trial).9
• The field needs to progress in a way that teaches clinicians to understand barriers in optimal care faced by certain racial/ethnic/gender groups.

9. Dr. Larry Jackson – what makes your heart flutter about electrophysiology and studying health inequity?

• The chance to provide equitable care.
• Equitable care is different from equal care. Equity implies acknowledging the differences between people of different races, ethnicity, genders, regions. These factors should be taken into account when offering therapies to our patients.
• It is not practical to offer different patients the same therapy, as they may have different barriers preventing them from utilizing that therapy.
• Optimal communication and assessment of patient goals with a focus on race/ethnicity/gender leads to better more personalized care.

1. Martinez C, Katholing A, Wallenhorst C, Granziera S, Cohen AT, Freedman SB. Increasing incidence of non-valvular atrial fibrillation in the UK from 2001 to 2013. Heart. Nov 2015;101(21):1748-54. doi:10.1136/heartjnl-2015-307808

2. Rodriguez CJ, Soliman EZ, Alonso A, et al. Atrial fibrillation incidence and risk factors in relation to race-ethnicity and the population attributable fraction of atrial fibrillation risk factors: the Multi-Ethnic Study of Atherosclerosis. Ann Epidemiol. Feb 2015;25(2):71-6, 76.e1. doi:10.1016/j.annepidem.2014.11.024

3. Lau CP, Gbadebo TD, Connolly SJ, et al. Ethnic differences in atrial fibrillation identified using implanted cardiac devices. J Cardiovasc Electrophysiol. Apr 2013;24(4):381-7. doi:10.1111/jce.12066

4. Mendys P, Jackson LR, 2nd, Solimon EZ, Howard G, Ferdinand K. The atrial fibrillation paradox -connecting hypertension to atrial disease and stroke. Am J Prev Cardiol. Dec 2021;8:100284. doi:10.1016/j.ajpc.2021.100284

5. Essien UR, Kornej J, Johnson AE, Schulson LB, Benjamin EJ, Magnani JW. Social determinants of atrial fibrillation. Nat Rev Cardiol. Nov 2021;18(11):763-773. doi:10.1038/s41569-021-00561-0

6. Norby FL, Benjamin EJ, Alonso A, Chugh SS. Racial and Ethnic Considerations in Patients With Atrial Fibrillation: JACC Focus Seminar 5/9. J Am Coll Cardiol. Dec 21 2021;78(25):2563-2572. doi:10.1016/j.jacc.2021.04.110

7. Ugowe FE, Jackson LR, 2nd, Thomas KL. Racial and ethnic differences in the prevalence, management, and outcomes in patients with atrial fibrillation: A systematic review. Heart Rhythm. Sep 2018;15(9):1337-1345. doi:10.1016/j.hrthm.2018.05.019

8. Golwala H, Jackson LR, 2nd, Simon DN, et al. Racial/ethnic differences in atrial fibrillation symptoms, treatment patterns, and outcomes: Insights from Outcomes Registry for Better Informed Treatment for Atrial Fibrillation Registry. Am Heart J. Apr 2016;174:29-36. doi:10.1016/j.ahj.2015.10.028

9. Meschia JF, Merrill P, Soliman EZ, et al. Racial disparities in awareness and treatment of atrial fibrillation: the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. Stroke. Apr 2010;41(4):581-7. doi:10.1161/strokeaha.109.573907

10.     Schnabel RB, Pecen L, Ojeda FM, et al. Gender differences in clinical presentation and 1-year outcomes in atrial fibrillation. Heart. Jul 2017;103(13):1024-1030. doi:10.1136/heartjnl-2016-310406

11.     Westerman S, Wenger N. Gender Differences in Atrial Fibrillation: A Review of Epidemiology, Management, and Outcomes. Curr Cardiol Rev. 2019;15(2):136-144. doi:10.2174/1573403×15666181205110624

12.     Magnani JW, Norby FL, Agarwal SK, et al. Racial Differences in Atrial Fibrillation-Related Cardiovascular Disease and Mortality: The Atherosclerosis Risk in Communities (ARIC) Study. JAMA Cardiol. Jul 1 2016;1(4):433-41. doi:10.1001/jamacardio.2016.1025

Dr. Larry Jackson is a cardiac electrophysiologist and assistant professor of medicine in the Division of Cardiology at Duke University Medical Center. Dr. Jackson is also an expert researcher, focusing on analyzing racial and ethnic disparities and the impact of social determinants of health on arrhythmia care.

Dr. Dinu Balanescu. Dinu is an internal medicine resident and upcoming chief resident at Beaumont Hospital in Royal Oak, Michigan. He also serves as House Faculty for House Jones in the CardioNerds Academy.