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Date of last update: 10/20/2017.

Forum Name: Cardiology Symptoms

Question: PVC every fourth beat- scared

 mnm1207 - Fri Sep 11, 2009 8:02 pm

I am 25 yr old female. I have had sinus tach for five yrs now, that really hasn't been helped. I recently had a thallium stress test that showed a blockage, which I went to duke for a 2nd opinion and had a cardiac mri. That showed no blockage and the dr did not recommend further tx. For the past two months I have had purplish nails, that no dr has been concerned about. They said my o2 is normal and not to worry. Last night I woke up with my heart racing and I was having pvcs every 4th beat. I called an emt and that is how I know. My heart was up to 161bmp, which happens often. The er sent me home wout any tests and said they were benign. Is that true? I always get pvcs, but not one every fourth beat. I am scared to sleep now. Will this lead to vtach?? What if I get a PVC at the wrong moment, doesn't that cause vtach? I am so scared and haven't been feeling right...which doesn't help. Oh and my nails aren't raynauds...I know that much. Any help would be great... A month ago according to the cardiac MRI, my heart was good. Could something change that fast?
 John Kenyon, CNA - Tue Oct 20, 2009 10:09 pm

User avatar Hi there -- While you may have something -- probably largely of nuisance value, but that remains to be seen -- going on, the PVCs are not the problem, and there are a tremendous amount of outdated notions still floating around about the matter. The fact is PVCs are almost never -- ever -- dangerous nor predictive nor diagnostic of anything. They are seen in most normal people, and so are almost always seen in those with heart disease. However, every fourth beat isn't really even "frequent" although if this went on for 24 hours you'd have had quite a few of them. It just doesn't matter and, in your case the reason they're happening is that your autonomic nervous system is causing them by trying to slow your heart's rate (the parasympathetic system, the vagus nerve, is the "brake" on the heart's rate, the sympathetic side the accelerator). The real problem here, if in fact there is one, is just why your heart is reaching unusually rapid rates for no apparent reason. It could be supraventricular tachycarida (SVT), it could be inappropriate tachycardia syndrome (ITS) or something similar. It's certainly worth pursuing, even though it's probably not dangerous in and of itself. It's exteremely bothersome at least. But the PVCs, no, that's just your body doing what's normal, and when the heart has something on the other side working against the brake (the accelerator pedal gets stuck while the brake is on) and PVCs naturally result from this. The goal needs to be to find what's causing the tachycardia, determine what's the best way to manage it, and get that program started so you can relax and feel better about this.

Regarding the positive nuclear scan/stress test, these are occasionally false positive, especially in women. Your problem isn't consistent, either, with cornonary artery disease. It could be consistent with some valvular abnormality, so an echocardiogram may well be in order, but even that seems unlikely. The purplish nail beds may well be a variation of normal, and as long as capilary refill (blanching with pressure on the beds followed by rapid recovery of color, even if its the "wrong" shade) is normal. I'm assuming that's been checked and you can even check this yourself by pressing on the end of one nail to see watch the bed blanch then the color return. If for some reason return of color takes more than 2 seconds, you may be suffering from dehydration, and this also could account for your increased heart rate, although routine blood work should have already exposed this.

The old notion that frequent or ill-timed PVCs has been largely discredited. Even in the setting of a frank heart attack half those who experience dangerous arrhythmias have not had that R-on-T phenomenon you're thinking of, that Ill-timed PVC. And half who have that phenomenon occur do not ever have a dangerous arrhythmia. Based on this knowlege we have essentially abandoned all but (unfortunately) the teaching of recognition of the phenomenon. Even having said that, there's no reason to assume any one of us -- and we all have PVCs from time to time -- might have an R-on-T PVC and if we did we'd be unaware if it anyway. In other words, no, those PVCs are not a cause for concern and in this case, in fact, show your body is trying to do things right. There's something else going on that would be useful to uncover. Holte

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