Atrial fibrillation (also called Afib) is an interesting disease. I would say it's probably the most complicated cardiovascular disease. That probably stands in line with atherosclerosis, right? So when you really talk about atherosclerosis, a lot of work has been done in this space for decades.
Secondary prevention, primary prevention, tertiary prevention, and genetic melio risk factors are all factoring into the equation. Similarly, the exact same risk factors that you really talk about at risk are also potential contributors, for the most part, for the atrial population as well.
And it is not a case where it just comes and goes away once you try to tackle it one time or two times. It is a systemic disease that is driven by underlying risk factors.
Atrial fibrillation (also called Afib) is a lifestyle and genetic condition that must be constantly modified and worked on in order for us to truly master atrial fibrillation (Afib). And really, to get anything meaningful in terms of success and control is a concern in treatment.
So rhythm disorder affects anywhere from five to six million people in the United States right now. I think it is equally important. With a significant burden on quality of life, stroke, congestive heart failure, and increasing tendency towards dementia, I think it is equally important. By all measures, this is probably the most important cardiovascular condition that we are dealing with now as part of atherosclerosis.
When you talk about atrial fibrillation (also called Afib), right? So there are three fundamental things that we take into consideration. People are obviously protected from the risk of strokes, since atrial fibrillation (Afib) (irregular heartbeat or heart beats) is a thrombogenic situation that contributes a lot more to both ischemic and embolic strokes.
So oral anticoagulation (treatment) based on the risk factor profile and arrhythmia burden is an important facet of it. So you have a plethora of oral coags that are available for treatment. And then the next important part is that for those patients that have very rapid ventricular rates or heart rates, how do you really slow down the heart so that it doesn't impact or minimize the impact on cardiovascular physiology?
Cardiac emptying, ejection fraction, and all those are important when you are considering a patients treatment. This is where medications like beta blockers, calcium channel blockers, and the ACS come into play.
And then you talk about rhythm control, which is where restoring the sinus rhythm means suppressing atrial fibrillation (also called Afib) and allowing the sinus node to take over or take control back and restoring the rhythm with the help of a drug.
Or rate frequency, cryoablation, or catheter ablation in general, is something to think about. So there are three fundamental tens. The first is the rate control anticoagulation strategy with AV nodal blockers for stroke prevention. And rhythm control, either with an antilithic drug and or catheter ablation, first line, second line, depending on whatever you have access to, I think would be the three important things to think about.
So, it's a hand and glove experience, right? Our general cardiology colleagues see a lot of the disease. They're the purveyors of general cardiovascular care and treatment. Electrophysiologists are more focused on arrhythmia care. As a result, it is critical for both the general cardiology and electrophysiology teams in a given setting to collaborate closely.
Depending on who sees the patient first, the other team needs to get involved in this patients treatment. For example, imagine a scenario. My general cardiology colleagues see a patient with atrial fibrillation (also called Afib) (irregular heartbeat). They have done everything that they needed to do, like getting the patient on an anticoagulant treatment and making sure that their ventricular rates are properly controlled with the right doses of blockers.
They've already initiated a drug, but then they're also simultaneously thinking about how do we expedite this patient's care so that we can actually decrease the burden of arrhythmia and the complications of arrhythmia that come out of it, because the old school thinking that somehow if you put a patient on an analytical drug, you really don't need to do anything else, has really gone away, right?
Atrial fibrillation (Afib) is a chronic condition, and it is not a question of if a patient is going to fail an analytical drug treatment. It's a question of when a patient is going to fail a drug treatment. So when you know that you are inevitably going to fail, which is the analytical drug that you're going to use, then what's the point of actually waiting until the drug fails? So you really need to have a strategy in place while I'm going to use this antarctic drug as a bridge to temporize the situation. and get my patient back into normal rhythm so that they don't have to pay the price of not being in rhythm. But I'm also making a choice that would help my patient to really fix this arrhythmia in a more definitive, curative fashion, which is where the catheter ablation comes into place for treatment.
It's wonderful to see that a large number of our general cardiology colleagues are thinking along these lines right away. They use the acute bridge with their antilithic drug treatment to get them temporarily stabilized. And then send them over for a catheter ablation to an electrophysiologist, but for the conversations at least about catheter ablation and really getting these (af) patients taken care of so that they don't have to be on antilithic drugs the rest of their life, so that they don't have to be on anticoagulation the rest of their life.
And also, discussing strategies like left rachel appendage occlusion and left rachel appendage management really becomes an important piece and parcel, on the other hand. I get to see a patient with atrial fibrillation (also called Afib) (irregular heartbeat) first, right? Then I consider, okay, I know I can get them rhythm control catheter ablation.
But then my patient has all these risk factors that need to be appropriately managed. They have really uncontrolled hypertension. They have dyslipidemia that needs to be addressed. They have diabetes, they have congestive heart failure. All of these things are not in my area of expertise. My general cardiology colleagues have a lot more expertise in taking care of these things. And so a tight conducive collaborative effort between the cardiologists and That, I believe this is critical in truly managing conditions such as atrial fibrillation, which is truly a team sport rather than an individual one.
It's a symptom is an interesting question, right? So I would say about 80% of (af) patients have symptoms of some form, or most of them are driven by rapid heart rates. That is, you feel palpitations because your heart is racing so fast. People recognize it immediately and then try to seek help.
And then, in some cases, it's just shots of breath, fatigue, being tired all the time. These are a little bit subtle. Symptoms frequently lead to a significant pedal because PE patients do not recognize the symptoms of heart failure or fatigue that they are experiencing.
But they don't feel a rapid heart rate, and the only symptom they have is fatigue. Most of the people, they are of an age where they think, "I'm just getting old and that's the reason why I'm not able to do what I'm able to do." That's the reason why a lot of these (af)patients don't seek help right away.
And these are the people that I really worry about quite a bit. And these are the (af) patients that often end up in the hospital with a really bad episode of heart failure, right? Because they have not sought any clinical help until they're really broken down, right? Until their hearts really gave up to the point where they said, "I can't take this anymore and I'm developing congestive heart failure."
Or somebody is presented with a stroke. It's unfortunate. A large number of (af) patients that present with a stroke are the ones that have atrial fibrillation (also called Afib) (irregular heartbeat), which is relatively silent. That means, I have mild symptoms or no symptoms. The only thing they notice is the first presentation of stroke, which I think is a terrible thing.
And then you have scenarios where people have really readjusted their lifestyle to things, right? Human beings are very adaptable. If you think about it, We stop doing things that we're not able to do, and you slowly kind of decline. And this is a group of people that we need to be. Be extra careful about asking them pointed questions, especially if they have a higher risk profile and a family history of atrial fibrillation (Afib) (irregular heartbeat).
We have got to be asking them very specific questions. One particular symptom that I find extremely helpful is what I call "the climb botany." So there are (af) patients that say, "Gosh, I really don't have any symptoms from my AFib (irregular heartbeat)." But I get into trouble when I try to climb a staircase. This is very important because climbing stairs is a physical exercise that really tests your cardiac endurance in many ways.
So it's actually an important test in heart failure patients. It's an important test in coronary artery disease. And it's also a very important test even for atrial fibrillation (also called Afib) (irregular heartbeat(af)) patients who otherwise say that they don't have any effect. Now, this is how I uncover symptoms in a lot of my patients by asking one question about dyspnea upon climbing a staircase.
When you think of care equity, right? If you are fortunate enough to live in a major city with access to numerous medical care institutions with well-developed programs where you can seek help right away, your story is very different from that of patients who live in inner cities, rural areas, or other areas where access to care is significantly different.
So when you really take the patient into consideration and really talk about health equity, we have got to think about how we can educate our patients better, right? How do we empower them with the knowledge that they really need so that they can make better informed choices about their therapy? If you really look at interventions or definitive therapies offered in medicine, the socialness of health really plays an important role in this, right?
So if you are a woman, if you are a person of color, if you are from a lower socioeconomic status, if you are from the inner city, if you are a rural patient, your ability to seek a particular definitive curative therapy is many times lower than somebody who doesn't fit that profile. And it is becoming very well established in many aspects of medicine.
That also includes cardiology, and that also includes access to ablation. So, as doctors, what can we do to shift the paradigm? What can we do as hospitals, healthcare institutions, or professional societies like the Cardiology Society, or ACC, or others, as a society in general? What can we do? To address and mitigate these inequalities that tend to be inherent to what we do on a day-to-day basis, right?
Access to care is an important facet of that. We educate our patients really well, whether it is social media, whether it is at the primary care physician's office, whether it is in the cardiologist's office, or whether it is special months like the AFI awareness month, like September, where you really launch a mass campaign and really work with the social media giants like Google on Twitter, someday on Instagram, and on Facebook to really make education an important piece of what we do.
And then there is something that you can do to change the paradigm of health inequity, which is how do you really tweak little things in workflow, right? Hundreds of patients, thousands of patients that come through the emergency rooms or primary care physician's offices. And these patients don't have access to care once they leave that emergency room or they don't know what to do once they leave that emergency room.
And this is where the ER to EP concept that we developed and worked upon as a pilot project really fits in very nicely in eliminating some of those health inequity related factors by leveling the playing field and taking away the hurdles and barriers to care in a significant fashion. Any opportunity that you have, if you as a patient come into a medical healthcare delivery system and you have a diagnosis of atrial fibrillation (also called Afib) (irregular heartbeat or heart beats), how can we facilitate that patient's care and really put them through rapid transit so that they get into the hands of a neurophysiologist for definitive care and get help right away, rather than going through the roundabout process of having to make an appointment with a primary care physician.
And then the primary care physician has to refer this patient to a cardiologist, and the cardiologist then has to refer the patient to an electrophysiologist, which typically consumes anywhere between nine to 12 months of that patient's process flow. While we are We are trying different medications and trying to figure out what works and what doesn't work while we are exploring these options.
So how do we really eliminate these barriers and then provide straight, easier access to definitive care by putting them in the hands of the electrophysiologist when you have an opportunity to do that? So that's exactly where the emergency room meets electrophysiology as a concept and really makes a huge impact on patient care, right?
We spend millions of dollars inventing new catheters and new energy ablations and different things to really change the needle with a very small game. But when you look at the process flow, you can eliminate a lot of these inequities in care and improve access to care by streamlining the process with a very simple order.
So Lira Pure Electrophysiology services and eliminate the barriers. The moment they step into the ER or into a private care physician's office, how can you get them into the hands of an electrophysiologist who can see them and provide them with definitive care? That's essentially a winner. And we have very clearly shown that in our study.
I think there are trials that we are working on multiple fronts. There are clinical trials that we're looking at a molecular level, whether you're talking about the new antilithic drugs or gene therapies for those patients who are genetically prone. Or you talk about newer forms of energy and new forms of catheters.
Pulsed field ablation is an exciting area that is really at the forefront right now. There are probably about 15 to 20 companies that have some form of pulsed field ablation technology or other that they're working on. And then you have therapies in the left atrial appendage management for stroke mitigation.
And then you have the whole area of risk factor modification. This is an area where the medical establishment has historically lagged behind, particularly in the Western world, particularly the United States. We haven't really done a good job with the primary prevention or secondary prevention, of really tackling the risk factors, whether it is exercise, obesity, or obstructed sleep apnea, and really getting aggressive with it and really creating a comprehensive Therapeutic opportunities, I think, are the next area. There's a lot of work that's coming out. And then, right, you have the whole social perspective of what we have done with ERPP, right?
I think removing barriers to access to care is an important facet that has to be worked upon. So it's actually wonderful to see that you have clinical work or research that's going on from a micro-molecular level all the way up to workflow processes and things like that. There are various people that are working on these concepts and a lot more exciting work that I think is going to come through.
I say atrial fibrillation (Afib) (irregular heartbeat or heart beats) is a chronic disease. We have great morbidity and mortality, and we really need to work together, and rather than worry about the territoriality of who's in charge of what, it doesn't really matter who sees this patient first. Isn't early intervention preferable to late intervention?
Thinking about the old at the age of a stitch in time saves nine. The longer we wait to get patients back into rhythm, the more difficult it is to care for these patients in the future, and the cost is quite high. He was working together as a team, keeping the patients in. At the heart and front and center of what we do, I think this is the most important thing for us to do.
I was always fascinated by medicine. I was probably inspired by my family doctor back in India. This guy literally saved my life from malaria, which was about to kill me. Right? Talk about dying from the most preventable causes of things in life, right? And that really was, I would say, a propelling factor in my personal desire and journey towards becoming a doctor.
And I was always fascinated by the intricacies of the human heart and just the critical nature of what cardiology meant. So, in medical school, there were many mentors who were inspiring cardiologists who clearly provided me with mentorship and inspiration. And then, during my implementation years, I always imagined myself as a plumber and an interventional cardiologist.
But then I changed my mind in my very first clinical rotation in cardiology as a cardiology fellow. I was given the opportunity to rotate through EP very early in my very second month. And the mentors there that I met were just incredible. And this was right around the time when radiofrequency ablation for atrial fibrillation (also called Afib) was really coming to the forefront in a big way.
At my very first AHA (American Heart Association) meeting in 2002, there was this massive meeting of the minds in a large lecture hall, with some of the space's thought leaders at the time discussing how they could actually curate atrial fibrillation (Afib), right? Leave it alone, just control it, atrial fibrillation (Afib) (irregular heartbeat or heart beats). I think that was a very fascinating experience to really see as the pulmonary veins get isolated, the atrial fibrillation (Afib) terminates, and then you have fibrillating pulmonary veins with normal sinus rhythm in the atrium of the heart. That's a very fascinating experience.
And that was a day I thought, oh gosh. I really need to be one of those docs that are sitting on this podium. and really be able to be part of this journey of understanding, innovating, and fixing atrial fibrillation (Afib). And that's my journey.
Dr. Dhanunjaya Lakkireddy is the medical director of the Kansas City Heart Rhythm Institute at HCA Midwest Health. Dr. Lakkireddy performs the sinus node sparing hybrid ablation technique to cure symptomatic, drug-resistant inappropriate sinus tachycardia (IST).
He specializes in electrophysiology, complex arrhythmia management (atrial fibrillation (Afib) (irregular heartbeat or heart beats), atrial flutter, ventricular tachycardia, supraventricular tachycardia), heart ablation, left atrial appendage closure; ablation, pacemaker and other device implantation and management, cardiac resynchronization therapy & pulmonary artery pressure sensors in heart failure, premature ventricular contractions, syncope, adult congenital and inherited heart disease. He's a leader in electrophysiological research and instruction and a university professor. Dr. Lakkireddy earned the Professional Leader of the Year award from the Asian Chamber of Commerce, the Prevention Magazine Integrative Medicine Award, and the Ingram's Heroes in Health Care Award. His honors mostly recognize his clinical research. He still leads clinical studies and investigations internationally. His electrophysiological research has appeared in 350 journals. Dr. Lakkireddy is also editor-in-chief of Journal of Atrial Fibrillation (Afib) and deputy editor of Journal of Interventional Electrophysiology. He reviews for more than 30 scientific journals, including the American Heart Journal, American Journal of Cardiology, Clinical Cardiology, Heart Rhythm Journal, and Journal of Interventional Cardiac Electrophysiology. Kansas ACP Governor. He's active in cardiology groups. He chairs the ACC Electrophysiology Council and is on the HRS Program Committee. He speaks in national and international heart conferences. Dr. Lakkireddy works for HCA Midwest Health in Kansas City, Missouri, and Overland Park, Kansas.
We are all aware that implantable defibrillators are the most effective kind of treatment now available to prevent sudden cardiac arrest. But because of the difficulties that are connected to leads, namely transvenous leads, there has been an interest in developing systems that do not utilize, that do not need transvenous leads, the potential difficulties linked with leads.
Valvular regurgitation, injury issues connected to extraction when it is necessary, and venous thromboembolism are all possible outcomes. Then there is the danger that is connected with the implantation, such as a pneumothorax. There, the existing subcutaneous system is highly successful; but, because of the distance between the ex and the subcutaneous system, it is not possible to achieve the same level of effectiveness.
The medical device is larger and sends eighty gems to the heart. Additionally, it has a larger size. The idea behind the Extravascular Implantable Cardioverter Defibrillator (EV ICD system) was to have a system that is not in the heart to eliminate all of the complications associated with the leaded system and to place the lead behind the sternum so that it's in a juxtaposition to cardiac tissue so that the amount of energy needed for delivering defibrillation therapy would be lower. This was accomplished by placing the lead behind the sternum.
Pacing for the treatment of atrial flutter can be both provided and paused. It is possible to provide both prevention and pacing. Because of this, the extravascular system was developed to perform this function, and an important study has shown that this is indeed the case. It was easy to carry out while remaining risk-free.
Regarding the effectiveness and security of an extra vascular EV ICD (system) clinical trial, you could say that. Participants in the EV ICD (system) trial were required to have either a class 1 or class 2 indication for the use of a defibrillator. Patients who had undergone bypass surgery in the past or who had thoracic abnormalities or a history of pericarditis in the past were not allowed to participate in this initial pivotal study because these conditions could make it difficult to insert a lead. The goal of the clinical study was to show that the tool worked, which was both the reason for using it and the reason for the study.
and that it was safe Its effectiveness was defined as the ability to successfully terminate ventricular tachycardia arrhythmias, and its safety (endpoint) was related to any major complications that were associated with the implant operation or follow-up through six months. The results of the test showed that the medical device was, in point of fact, quite successful, as the researchers had hypothesized.
The percentage of patients for whom successfully delivering defibrillation therapy was performed was 98.7%, which was significantly higher than the pre-defined performance goal of 88%. And in a similar fashion, the safety threshold with EV ICD system or procedure associated issues at six months was 90, and freedom from was 92.6%, which was higher than the pre-specified performance objective of 79%.
So, the EV ICD (system) trial proved that the extravascular implantable cardiac device (ICD) needed it, but it still met its safety (endpoint) and performance (to help prevent sudden cardiac death) standards.
A few aspects of the EV ICD (system) trial that, upon further consideration, might prove to be fascinating Before anything else, this apparatus is positioned so that the lead is underneath the sternum, which is not a location. An electrophysiologist is a typical specialist that cardiologists access. Therefore, the demonstration that an experienced electrophysiologist could be effectively trained to perform the procedure was an important factor to take into consideration. This demonstration required a training program with cadavers and animal labs, and the first few cases had to be done in front of a cardiac surgeon.
Frequently, not in an operating room setting, but rather in the controlled atmosphere of an EP lab. In point of fact, investigation revealed that to be the situation. However, that is a significantly different form than what I was expecting. So, in the manner that the implant procedures are carried out in the process suite, there is a tunneling instrument that is moved forward once the sternum has been dissected and brought closer to xIPHi.
In addition, this tunneling tool resembles a metallic rod, which can be seen on fluoroscopy, and it is positioned directly behind the ship's stern. Additionally, it is observed in the lateral fluoroscopic view, which enables one to see quite clearly where it is situated in relation to the sternum. After it has been put into place, it is removed, and in its place, a standard sheet is left for the deployment of a lead.
The lead was successfully deployed in the substernal position, and the success rate for doing so in this new location was 99%. They were all practically effortlessly put into action without a hitch. To demonstrate, once more, both the safety and effectiveness of the medical devices, as well as the fact that these new sorts of medical devices could be administered by cardiologists, was an essential component of the EV ICD (system) trial that needed to be tested.
Since you asked about my interest in cardiovascular medicine, I've always been interested in the field. My interest in physiology began early on, particularly in the physiology of the cardiovascular system. In fact, I was initially matched in an anesthesia program; however, I discovered that the care of patients with cardiovascular disease, the opportunity to make a difference, the opportunity to manage acute and chronic disease, and truly advance science was so appealing that I decided to switch to that instead.
I consider it a great honor to be able to work in the field of cardiovascular medicine and to take part in fascinating studies that test out innovative treatments and technology that can improve patient outcomes in novel ways. We couldn't even let a man try to imagine what I was working toward in my training.
When you first get a very robust and optimistic signal, there are a few things that you should keep in mind, including the fact that we still need to identify them in more general populations. It is put to use. In the United States, the medical device is now going through the process of getting approval from the government.
Even if it does occur, I believe that we will continue to grow as learners as we always have done with extra experience. Who stands to gain the most? How effective are the treatments for avoiding SL heartbeats, and how frequently can we apply them? Will it help prevent sudden cardiac death and help cardiac rhythm? These are the anti-bradycardia pacing therapies. And, the early indications are that they are typically extremely well tolerated. However, it is unclear how well they are tolerated, in which patients, and whether or not there are other implant techniques that could make pacing more or less well tolerated. Therefore, I believe that there is a great deal of nuance to be learnt about how we might most effectively use the new tool.
In conclusion, the extravascular implantable cardioverter defibrillator (ICD) was shown to be both safe and efficacious in this prospective worldwide EV ICD (system) clinical trial. In addition, this is an early experience, but it is a promising one that shows that we now have a new tool in our arsenal to prevent sudden cardiac death to administer antitachycardia pacing and pause prevention pacing. This is applicable to patients who have not undergone a sternotomy in the past.
Paul Friedman, MD—About The Author, Credentials, and Affiliations
Dr. Paul Friedman is not only a professor of medicine at the Mayo Clinic in Rochester, Minnesota, but also the head of the department of cardiovascular medicine there. He is board-certified in cardiovascular medicine and cardiac electrophysiology by the American Board of Internal Medicine (ABIM), and he is an engaged participant in the Maintenance of Certification process.
Before joining the Mayo Clinic, Dr. Friedman worked there as the director of the Cardiac Implantable Device Laboratory. He is a licensed electrical engineer with substantial experience in both scientific research (> 250 original scientific articles) and creativity (> 40 issued patents; dubbed Minnesota's Top Inventor). He has been awarded the title of Minnesota's Top Inventor. In addition to writing over sixty book chapters and serving as the director of five different national and international conferences, he is also the editor of seven different textbooks. He participates in a significant number of educational conferences both as a lecturer and as a visiting professor.