What a heart patient can expect at an electrophysiology appointment
Host Amber Smith: Upstate Medical University in Syracuse, New York, invites you to be The Informed Patient with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith.
If your heartbeat is too slow or too fast or irregular, you might be referred to see an electrophysiologist. Today, we'll talk about what to expect at an electrophysiology appointment with Dr. Kiran Devaraj. He's a cardiologist at Upstate who specializes in electrophysiology. Welcome to "The Informed Patient," Dr. Devaraj.
Kiran Devaraj, MD: Thanks for having me.
Host Amber Smith: I'd first like to ask you to explain the background of an electrophysiologist. You're all medical doctors who specialize in cardiology, and then you subspecialize in electrophysiology.
Is that right?
Kiran Devaraj, MD: Correct. Yes. Usually an adult cardiologist will train in adult medicine, or a pediatric cardiologist soul train in pediatric medicine, followed by subspecialty training in cardiology, and those who have an interest in heart rhythm problems will then go on and do additional subspecialty training in what we call clinical cardiac electrophysiology, which means that we treat heart rhythm problems for patients.
And our research colleagues are called a basic science electrophysiologist. They do more experimentation and cell-based research and molecular research. So my full title is a an adult clinical cardiac electrophysiologist, which is a bit of a mouthful for most patients.
Host Amber Smith: It is. Well, when someone's doctor, their primary care provider, flags an irregular or a fast or a slow heartbeat and says they need to see an electrophysiologist, how would you advise that person to prepare for that visit?
Kiran Devaraj, MD: Sure. So most of my referrals come from patients who already have, at a minimum, a primary doctor, but even a cardiologist.
So a lot of these patients have already had some form of testing. They might've had an electrocardiogram to look at, which is a basic test that a lot of patients are offered by their cardiologist or by their primary doctor. They may be offered a heart rhythm monitoring such as a Holter monitor that they wear for a few days to catch heart rhythm problems or event monitors, which are longer heart rhythm monitors. They can be worn for weeks at a time.
And then they may getother testing, too, before they come to see me. They may get things like an echocardiogram, which is an ultrasound of the heart, or a stress test to look for any signs of underlying coronary artery disease or heart rhythm problems.
Host Amber Smith: So would a person be referred to someone like you, if those tests that they've already undergone don't offer an answer? I'm imagining that it might be a little bit scary to be told, "Well, you know, we've gotten all these tests, and now we need you to go see this other specialist."
Kiran Devaraj, MD: If anything, it's the other way around. If the testing is abnormal, if it's not normal. So if it shows signs of a heart rhythm problem, then they'll typically see me. But if someone's having palpitations, but the arrhythmia testing is actually reassuring, so there's no signs of a heart rhythm problem on a Holter monitor or an event monitor, uh, they're less likely to be referred.
There are non-cardiac reasons why someone can have palpitations or racing heart rate. Common things include things like thyroid problems or anemia or anxiety. So typically that's why, when a patient sees their primary doctor for those kinds of symptoms, they won't just be looking for heart problems. They can also look for other problems, too.
Host Amber Smith: So what is the first visit with you typically like?
Kiran Devaraj, MD: It depends, partly because, as I stated earlier, a lot of patients already have, to some degree, been diagnosed before they see me, whether through their primary doctor or through their cardiologist. They've often already had testing like the electrocardiogram or the Holter monitor or the echocardiogram. Usually at that point, a lot of information's already been gathered. And so what I try to focus on for people who already have a diagnosed heart rhythm problem is to go over their symptoms and essentially to explain to people what's going on, how worried they should be about that problem and what are next steps, versus for people who don't have a diagnosed heart problem, like, say, they have a symptom, but they don't have any testing confirming a heart rhythm problem -- then we talk more about further testing.
Host Amber Smith: Of the dangerous heart rhythms that people may be walking around with, which ones require treatment most urgently?
Kiran Devaraj, MD: The urgent ones are usually people are headed to the hospital already. So the most common cause of dangerous heart rhythm problems is coronary artery disease in the U.S., in adults.
The incidence of coronary artery disease is 6% to 7% in the United States. And if left untreated, coronary artery disease can then lead to dangerous heart rhythm problems, like ventricular tachycardia and ventricular fibrillation. And those are somewhat common reasons why people end up in the hospital due to dangerous heart rhythm problems as a result of heart attacks and untreated coronary artery disease. So I see patients like that on a semiregular basis.
And then other common heart rhythm problems, like atrial fibrillation or SVT, those are a little bit more variable because you were talking about how serious these things are. Some patients with atrial fibrillation, we see them in the office. Some patients with severe symptoms get admitted to the hospital. It depends a little bit on the particular patient.
Host Amber Smith: It sounds like there's quite a range.
Kiran Devaraj, MD: There is, yes. The same heart rhythm problem can present very differently from patient to patient, which is why I'm being a little bit vague intentionally.
Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith, talking with Dr. Kiran Devaraj, a cardiologist who specializes in electrophysiology at Upstate.
If someone's heart rate is too slow, what might concern you, and what types of things would you be looking for?
Kiran Devaraj, MD: Sure. First, I want to state that normal is a loaded term when it comes to heart rate, as it is for a lot of other medical measurements, because what's normal for one person might actually be not normal for another person. Like for instance, a newborn baby, their resting heart rate could easily be 160 beats a minute, which for an adult is obviously very different.
And for a professional athlete, their resting heart rate may be 50 beats a minute or even 45 beats a minute, which would be considered too slow for a normal adult, but would actually be considered an entirely appropriate for a highly trained athlete. So with that in mind, I mean, technically the lower limit of normal for heart rate is 60, but as I just stated, it's considered acceptable for people to have heart rates in the 50s, particularly if they are athletes or if they have an underlying medical problem that might make their heart rate a little bit slow. Typically if people have heart rates in the 40s, that's considered somewhat more unusual, but even then, some athletes do have heart rates in the 40s.
And then in terms of symptoms, things to look out for would be things like fainting, passing out, having lightheaded spells. Those are signs that those slow heart rates are actually not allowing enough blood to reach the brain and therefore affecting cognition, or if you generally just feel tired and unable to have enough energy to do normal things like walk up flights of stairs and do normal activities of daily living, that's a sign that slow heart rates could be effecting your physical activity. And that's usually confirmed by things like an electrocardiogram to look at your resting heart rate, a Holter monitor to see what your heart rate ranges during an entire day, and then sometimes even a stress test to see what your heart rate does both at rest and with exercise.
Host Amber Smith: Is it normal for a person's heart rate to become slower as they age? And maybe they're not as active as they used to be, or maybe they do have some heart disease. Is it normal for the heart to kind of slow down?
Kiran Devaraj, MD: Yes, in a word. So your natural pacemaker is called your sinus node, and that typically governs your heart rate, in conjunction with your brain and your brain stem and a certain part of your nervous system, which is called your autonomic nervous system. And those heart rates governed by your natural pacemaker and your brain. Those do actually slow down with age. So typically people develop what's called sinus node dysfunction or slowing of their natural pacemaker, as they get older. It doesn't happen to everyone, but that's why it's the most common ages for a pacemaker implantation are older adults in their 70s and 80s, due to age-related sinus node dysfunction.
And then secondly, heart block, or AV (atrioventricular) block, is where the electrical system of the heart becomes aged and calcified. And the conduction system, the wires that control signals inside the heart, can sometimes fail and cause some slowing of the heart rate. And that also is most commonly in people in their 70s and 80s.
Host Amber Smith: I know it varies from person to person, but what about rhythms? Do you see rhythms that are too fast? A person whose heart is just beating too fast, constantly?
Kiran Devaraj, MD: Yeah. The two most common scenarios for that are superventricular tachycardia, which is often abbreviated down to SVT, and then atrial fibrillation. SVT is not just one heart rhythm problem; it's actually a family of different regular fast heart rhythm problems. SVTs, statistically speaking, most of them are due to some kind of abnormal loop or re-entrance circuit, as we like to call it, inside the heart. And that endless loop can allow the heart rate to go too fast. And whether that's 130 or 140 beats a minute, or sometimes even as fast as 250 beats a minute, that can cause someone palpitations and racing heart rate.
And while that sounds scary, SVT is actually considered a benign heart rhythm problem. It doesn't cause heart attack or stroke or heart damage. And people are usually treated for their symptoms, versus another rapid heart rhythm problem, which is called atrial fibrillation.
That's more common as people get older. That typically happens to people in their 60s and 70s and 80s. The typical incidence starts to be about 10% in people in their 60s, and that's associated with common things like high blood pressure and being overweight and snoring and sleep apnea and a variety of different heart and lung problems. And atrial fibrillation is more medically serious because that's actually associated with a risk of stroke, and the risk of stroke is the find based on other clinical risk factors.
Host Amber Smith: If someone comes to you with an irregular heart rhythm, or it's too fast, or it's too slow, how do you determine whether that is caused by a medication that they're taking?
Kiran Devaraj, MD: That's a great question. It mainly comes down to figuring out the timeline of symptoms. Most commonly, if they started a medicine recently, whether it was a few weeks ago or a few months ago, and then the patient may not have connected it for themselves, that their symptoms started after the medication was given.
And then we walk through those kinds of timelines. And that's most common with things like antidepressants can cause slow or fast heart rates; some other psychiatric medications can do that. Oral contraceptives are a common reason why people cannot feel racing heart rates. Honestly, I see all kinds of medication side effects that I happen to diagnose in daily practice (chuckles).
Host Amber Smith: You mentioned the word "pacemaker" when we were talking about the slow heart rhythms. Are pacemakers only for when the heart's too slow, or are they sometimes used if the heart's too fast?
Kiran Devaraj, MD: Yeah. The purpose of a pacemaker: It's a medical device that's implanted in the body, and typically there's at least one or more wires, which are implanted inside the heart, to regulate the heart rate to prevent it from being too slow. So in that sense, the pacemaker is primarily a treatment for slow heart rhythm problems. The main reason why it would be offered to someone with a fast heart rhythm problem is that if they're having a fast heart rhythm problem, and for some reason they can't get the right medicines, they need to slow their heart rate down. So they need a pacemaker to prevent any slow heart rates and to allow them better medical therapy. But yes, the pacemaker is mostly for people with slow heart rhythm problems.
Host Amber Smith: So do electrophysiologists install the pacemakers?
Kiran Devaraj, MD: Yeah, historically. Well, I mean, pacemakers have been around now for almost 50 years. When they originally came out, they were typically implanted via open-heart surgeries. A lot of the first pacemakers were implanted by surgeons. And that slowly evolved. It started to be more cardiologists were doing them. And then my field, cardiac electrophysiology, is actually a relatively young, and it was essentially born by the fact that these pacemaker systems became more complicated.
And we were learning about all of these different heart rhythm problems, and they require more specialized treatments. So that's how my field was born in the last 30-40 years.
Host Amber Smith: How long does the pacemaker last, if you install one for someone today? Do they last many years, or do you have to change batteries?
Kiran Devaraj, MD: There's two components to a pacemaker system. There's the actual peacemaker itself, which houses the electronics and the battery for the device. And then there are the pacemaker wires, which are implanted in the body permanently. The typical lifespan for a pacemaker is eight to 12 years, and that's governed by the battery life.
And, by contrast, there's a different kind of device that we implant that's called an implanted cardioverter-defibrillator; the battery life on those devices is a little bit lower, more like five to 10 years. And then the wires that go with a pacemaker, the lifespan of those devices is a little bit more variable.
The pacemaker wires can break down over time, which is rare. I tell people it happens about 1% to 2% per decade at first, but typical pacemaker wires can last 20, 30 years. And that's partly based on just most of the modern pacemaker wireshave only been around for 20 or 30 years (chuckles).
Host Amber Smith: So while someone has a pacemaker, they continue to have checkups with you as long as they have the pacemaker?
Kiran Devaraj, MD: Yes. Usually if you have a pacemaker, you have a cardiologist or a cardiac electrophysiologist who has the monitor of the device. The best analogy that I give to patients that it's like owning a car; you have to take it in for regular maintenance. So, checkups to make sure that it's working properly. And then the service is essentially replacing the battery, as I said, eight to 12 years for pacemakers and five to 10 years for defibrillators.
Host Amber Smith: This has been very interesting. I appreciate you making time for this interview, Dr. Devaraj.
Kiran Devaraj, MD: It was great to be here. Thanks for having me.
Host Amber Smith: My guest has been Dr. Kiran Devaraj, a cardiologist specializing in electrophysiology at Upstate.
The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe. Find our archive of previous episodes at upstate.edu/informed.
This is your host, Amber Smith, thanking you for listening.