Severely increased left atrial volume, and PACs

[hoovlet]

I am a healthy, fit, and very active 47 year old woman--healthy lifestyle and diet, runner, and I ride my bike for transportation. Resting HR of 52. PACs started a few weeks ago, so got a Holtor which reported over 4000 PACs/24 hours (that was half of what they had been previously), sleeping HR went as low as 41. Had an echocardiogram the other day, and everything was normal, except: "severely increased left atrial volume." Mysteriously, left atrial *size* (i.e., diameter) was normal. My appointment with the cardio doc is not for over a week, and in the meantime, my PACs have returned after a run (I took a break from running and PACs had subsided) and I'm quite concerned about this apparent result. I have examined the scientific literature and it seems that severely increased volume is indeed concerning and predicts all kinds of dire events. However, I came across no reports of increased volume without increased diameter, so the results are confusing.

The cardiologist I will see took a quick look at the results at the request of my doctor, and he said that since everything else was normal, the "severely increased LA volume" was "likely a mistake." But I sit here with my four year old, feeling these intense PACs, worried that it is, in fact, not a mistake and I have some worrisome condition.

Question: does anyone know if it is possible to have a severely increased left atrial volume with normal left atrial "size," i.e., diameter? Can this have anything to do with "athlete's heart"? I only run about 12-15 miles a week and don't bike more than a few miles a day, so I don't think I'm so well trained as to have athlete's heart (as far as I can tell).  I assume that many of you feel as I do--in the dark, with disturbing chest sensations, and scared of some sort of sudden death or stroke that will leave me unlike the woman I am now.

Thank you!

[hoovlet]

Hi Jerry,

This was my first post, so I appreciate such a rapid and sensible reply! In answer to your question, evidently everything (I assume including valves) was normal on my echo. I'm going to try to carry on normally until my appointment! I'll let you know how it turns out.

Thanks!

[Jerry_NJ]

I vote the warning is a mistake... I can't understand either how one can have more volume and no diameter change.  The diameter is the only measurement in an echo that I know of that check on chamber size, the diameter implies a volume.

No concern either I think about exercise, that works your ventricles not atrium chambers --- yes both operate at a higher rate but the ventricle does all the work.

A leaky mitral valve can cause left atrium size increase, suppose the corresponding valve in the RH side can cause the same.  An echo checks all valves, how do yours "look"?

I have added your post to my watch list so I can follow along, in the meantime I say go on with life it doesn't sound like you have anything to worry about, check yes,worry no.