What I think has been proven in studies is that someone throwing "benign" pvcs or pacs in a structurally normal heart has the same chance of developing a dangerous heart rhythm as the general population.
Your chances of throwing a malignant ectopic is the same as someone who doesn't get ectopics. We are all at risk for it. Then again, we are all at risk for getting struck by lightning.
Now like the others have said, if you have underlying illness in your heart, that's out the window.
Hope that makes sense.
These studies are failry recent and has changed the way docs approach treating PVCs. 10+ years ago they treated them as being dangerous and treated accordingly. Now, they send you home and tell you to make better lifestyle choices.
well they are normal but have the potential under the right circumstances i.e. previous MI, scaring, drugs, enlarged heart muscle, more possibilities than I can think of.. can trigger a domino effect of arrhythmias that "can" be (have the potential to) fatal. crappy example but it paints a picture, jumping on a trampoline when its done right, jumping too high happens some times and nothing happens, then jumping too high and recoiling into the near by tree can mess you up. PVCs can happen to anyone for no apparent reason (only speculative) and it doesn't have to mean an underlying condition, hell teenagers can have them. ya know. guess that's the easiest way of explaining what I meant
What I do understand is , "Both are common (60% occurrence), both are "normal" (benign) and both are capable of having the propensity to cause life threatening complications (arrhythmias i.e. SVT or V-FIB). "
So both are "normal" and "benign" but both are capable of causing life threatening complications. Now I am no English major but isnt that a oxymoron. How is something normal and benign but it could kill you?
Hello, and thanks for nice words and a very interesting reply. Just a thought first, I know what you mean by this "research mode" but I will strongly recommend you not to do this. The reason is, I've done it myself, and it won't do you any good, except if you're planning to be a cardiologist (I'm actually considering that, but not sure if I want 12 more years at school :)
Reading cardiology topics will, in most cases, produce more anxiety. It's very complicated stuff, that must be read in its right context. And I'm NOT good at that.
To the "what is most dangerous" I believe this can be estimated different ways. I believe a PAC easier than a PVC can be "productive" of other events (sustained arrhythmias, fibrillation, etc), though the consequences are less severe (Afib vs Vfib or SVT vs VT).
To classify the danger from PVCs, "Lowns scale" was used, it estimates the risk by the levels: No PVCs, rare PVCs, Occational PVCs, multifocal PVCs, couplets, and R on T (as you mention).
The R on T phenomenon is what I call the "king of cardiac neurosis". I believe, however, cardiologists disagree on how important this phenomenon really is, anyway it's rarely an issue except in hearts with severe conduction abnormalities or, of course, long QT syndrome, where they induce TdP. Anyway, in healthy hearts, I seriously doubt this is a common problem, and it rarely induces any problems if someone is unlucky enough to get one. They don't induce Vfib directly, but can probably cause both monomorphic VT and polymorphic VT (Torsades), that can possibly degrade to Vfib. Anyway, it's a very rare phenomenon.
I know I have PACs and I notice them, indeed. It's very different how well I notice them, though, and it's dependent on (among other things) my blood pressure. With high blood pressure, the "thud" beat (normal sinus beat after a PAC) is far more noticable. If my heart rate is low and blood pressure is low, the compensatory/noncompensatory pause after the PAC is more noticeable, creating the nasty, couple of seconds long, strange feeling in my chest. This is more noticeable with a PVC since the pause is longer.
Anyway, if you're not monitored on ECG, speculations about what the skipped beat was caused by is waste of time. You will never get an answer, and it doesn't really matter. If your heart is healthy, both are benign.
forgot the other occurances of pvcs...ooopsy
3) two consecutive PVCs = "pairs" or "couplets"
4) PVCs with the same pattern = monomorphic
5) PVCs with different patterns = polymorphic
Thank you for your reply, it very informative as well as stress relieving. And encouraged me to dig deeper. My disclaimer/apology for endless banter:
I get paranoid sometimes and need to research the heck out of something to set my racing mind at ease. An affect of my ADHD.
I think you’re right about a short run of bigeminy; as it was likely a PVC every other beat instead of 2 in a row, a couplet. I might disagree with you on one part though, the PAC. I know for certain what a PVC feels like because wearing the event monitor, I would press record when I would feel what I described the funny feeling (almost feels like it takes your breath away, or that when you feel it the initial response is to try and take a big breathe in) and the Hard ventricular contraction or thud after. Those events were recorded and the cardio said it was a PVC and not to be concerned there normal. So knowing what PVC's feel like and also from what learned while I shadowed a Telemetry unit (central monitoring unit) at a hospital for my physiology of EKG course; is that most people don't feel PAC's vs. PVC's one not necessarily more potentially dangerous than the other.
In a way it got me thinking and in research mode, a habit I’ve developed in undergrad to ease my mind when a subject concerns me. So I pulled out text books, medical dictionaries, the PDR you name it. Shot a few emails to an M.D. friend and a few college professors I keep in touch with, to better aid in confirming my hypothesis or finding it null. Here is what I found out:
*PACs Premature Atrial Contractions or Complex ({Contraction, referring better to the physiological or what’s happening.} Whereas the Complex, is more specifically referring to the beat and better describing how the wave looks on an EKG).
PACs are a result of abnormal electrical impulses that arise from the atria. Again, no cause for alarm just yet because 60% of normal adults experience them on a 24-hour Holter monitor. In serious instances the cause for concern is that PACs can initiate supraventricular tachycardia or SVT. In PACs the ectopic P wave is often hidden in the ST-T wave of the preceding beat.
Fig. 1.1
This figure Illustrates the obvious identification in the difference between PVCs and PACs on an ECG strip. (link to image fig 1.1)
http://www.pharmacology2000.com/Cardio/Cardio_risk/adult_cardiac_procedures/pvc1.gif
*PVCs are common arrhythmias, not necessarily associated with heart disease. They can occur singly or in 5 different variations;
1) Bigeminy - every sinus beat followed a PVC
2) Trigeminy - 2 sinus beats are followed by a PVC
3)
PVCs are normal and safe the biggest majority of the time. The consensus by multiple studies conclude they're prevalence to be > or = to 60% in men. By themselves, they are not associated with increased mortality/morbidity; however, in patients having previous myocardial infarction, and PVCs occurring at a rate >10/hr is associated with increased mortality. As stated before, PVCs are normal and benign mostly. Where one runs into complications, is when a PVC triggers an event like Ventricular Fibrillation or V-Fib for short. This is most commonly associated with very early cycle PVCs when the R-wave is on the T-wave. An example of R- on T-wave induction of V-fib is illustrated in the ECG strip fig 1.2 (link to Fig 1.2)
http://www.pharmacology2000.com/Cardio/Cardio_risk/adult_cardiac_procedures/R_on_T2.jpg
Both are common (60% occurrence), both are "normal" (benign) and both are capable of having the propensity to cause life threatening complications (arrhythmias i.e. SVT or V-FIB).
That's seems to be the word around the campfire any way. This is just what I found on the subject, And wanted to share it.
Sources:
WebMD
Taber's cylopedic medical dictionary
The Only Ekg Book You'll Ever Need (4th Edition)
PDR 2008 edition
Online figures from their respective links
I would have to agree with is_something_wrong,
There shouldn't be anything to worry about. Although it is really annoying and scary to feel irregular beats they are far from life threatening, especially since you are in your prime and in such good shape.
Should they become worst see you cardio. again and discuss treatments options. There are some meds that do not affect exercise performance and have a tendency to stop ectopic beats. Ex: Propafenone
Iane F.
It's important to know that if you should choose between PVCs at rest, or PVCs during exercise, you should definitely prefer PVCs at rest, as they are completely normal. What you are experiencing (from what you describe) is not a PVC couplet, it's a brief bigeminy run. You cannot even be sure this is PVCs, it's just as likely they are PACs.
PVCs (or PACs, that are more common in this setting) during exercise can in younger people be a sign of high anxiety levels or poor exercise condition, as your heart is at high stress levels and starts to create ectopic beats to help increase your heart rate.
If your heart is structurally normal, PVCs do not increase your risk of cardiac events.
By the way, it seems like in US, people always believe they have PVCs. In Europe, this seems different, and I've read from Norwegian cardiologists that "in younger people, far the most ectopic beats origin in the atrias, and it's usually more correct to name them "narrow complexed PACs" or "wide complexed PACs" than PACs or PVCs." Anyway, it's not easy to see if an ectopic beat is a PAC or a PVC on an event monitor, and I suspect that several of your ectopic beats actually are PACs, not that it really matters. In a structurally normal heart, both of them are benign.