Palpitations and PVCs: Why Worry?

 

Matthew F. Watto, MD: Welcome to The Curbsiders. I'm Dr Matthew Frank Watto, here with America's primary care physician, Dr Paul Nelson Williams. This was a classic podcast episode, where we talked about palpitations with Dr Josh Cooper. Tell me, Paul, what was your favorite take- home point from our conversation?

Paul N. Williams, MD: We talked about premature ventricular contractions (PVCs). We often think of PVCs as a symptom of a sick heart, and not as actually causing cardiac pathology. We see them on an EKG and we think, That's weird. So we check the patient's electrolytes to make sure we're not missing something, then we go on our merry way and assume that we've done the most that we can. Dr Cooper was sharing with us that a PVC burden > 10% can actually lead to cardiomyopathy. PVCs are often dismissed in the setting of normal electrolytes and a bare-bones workup, and not thought about further. But they probably warrant investigation by someone who deals with them all the time, whether we're talking ablation or medications or other options. Since our podcast, I've been taking PVCs more seriously than I had up to that point.

Watto: Me too. When I read a Holter report, I look at the PVC burden. If it's < 1%, it's not as worrisome as if it's 10%. Dr Cooper told us that the heart beats 100,000 times a day. So, 10% would be 10,000 PVCs a day, and that can be enough to cause cardiomyopathy, which is scary. 

Sinus tachycardia is another thing that people tend to write off: Oh, it's just sinus tachycardia. I'm terrified of sinus tachycardia. If I have a patient in clinic with a heart rate of 115 beats/min at rest, I'm worried. Why is their heart rate 115 at rest? Maybe it's because you walked in the room and you're America's primary care physician — just to be in your presence gives them tachycardia. But you need to figure that out. There are so many reasons for that. I don't know about you, Paul, but I do investigate. 

Williams: From time to time, I will ask a trainee about a patient's tachycardia, and they will say the patient is always tachycardic. That is the least reassuring thing you could say — it sounds really bad. So I agree with you. It's not unusual to be a little bit tachycardic when you're at the doctor's office or in the presence of greatness. But do your due diligence and make sure you aren't missing some underlying cause.

Watto: Dr Cooper mentioned the common things that can cause tachycardia: anxiety, pain, dehydration, or a medication the patient is taking. You might need to check a TSH to make sure it's not hyperthyroidism. I once diagnosed Graves disease before I even examined the patient because I walked in and the heart rate was 125 at rest and the patient was kind of tremulous. I thought, I bet this person has hyperthyroidism and it ended up being Graves disease.

There's also a diagnosis of exclusion — I don't know that I've ever made it — but it's basically idiopathic inappropriate sinus tachycardia. Depending on how long that goes on, if it's fast enough, it can lead to cardiomyopathy. So, I wouldn't just throw a beta-blocker at that. Investigate it, make sure you're confident about why this tachycardia is happening and is it happening outside your office? If so, it might be worth sending them to cardiology. 

Let's say you are working up a patient who came in with palpitations. If you find PVCs, that's probably what the patient is feeling. Or maybe you find sinus tachycardia. But what if you find nothing? What do we do then? 

Williams: I really liked Dr Cooper's framing of this. Their symptoms mean that something is going on. You can have a conversation saying that you've done a very thorough cardiac workup, and you are fairly certain that the symptoms are not coming from their heart, and that's good news. That means their heart, at least, is not going to kill them. 

But even if this is something like anxiety, anxiety is a medical condition that warrants evaluation and appropriate treatment. So rather than saying, Well, don't worry, this is nothing to worry about, we need to acknowledge that the symptoms are present, something is causing them, and we need to figure out what to do next. Dr Cooper then makes his best guess and connects them with whatever specialist that requires. He may even send them back to their primary care doctor, who might be best equipped to manage it. But rather than saying Don't worry, everything's fine (because that doesn't mean their symptoms are gone), we should tell the patient that their symptoms are probably not cardiac, and we will figure out what to do next to find out what is causing the symptoms. 

Watto: In my experience, a lot of patients who come in with palpitations are really looking for reassurance. They have a sense that it's probably nothing too serious, because in some cases it's been going on for years. It's kind of a fleeting feeling, and they have never passed out or anything — they can exercise. They just want you to say, Maybe this is nothing. And once you get that monitor data and you can correlate their symptoms with their rhythm and show them that it's just sinus rhythm, many patients are reassured by that, and I am too. But if it isn't, you can offer them anxiety treatment, like Dr Cooper said. Patients don't like it when you just blame everything on anxiety, so taking them through it and showing them that you are taking it seriously helps. You can still offer treatment even if you don't find a dangerous cardiac rhythm. 

If you want to hear more about palpitations, because we did discuss a lot more in our podcast with Dr Cooper, then click here. 

https://www.medscape.com/viewarticle/palpitations-and-pvcs-why-worry-2024a1000904