PR interval decrease - good or bad? - Heart Disorders Message Board

flowergirl2day · 08-02-2007, 02:05 PM

Hi,

I would appreciate your input. I had an ECG done recently before treating a really bad edema and don't have a copy of the test result. I do know (from my physicians's notes) that besides the ever present Left axis deviation (there's a reason for that and it's nothing new), a marked decrease was noted in the PR interval. What does it mean?

Thank you,
Flowergirl

started04 · 08-03-2007, 11:02 AM

Quote:

Originally Posted by flowergirl2day

Hi,

I would appreciate your input. I had an ECG done recently before treating a really bad edema and don't have a copy of the test result. I do know (from my physicians's notes) that besides the ever present Left axis deviation (there's a reason for that and it's nothing new), a marked decrease was noted in the PR interval. What does it mean?

Thank you,
Flowergirl

Flowergirl, the PR interval relates specifically to the upper chambers, and the interval should be long enough (electrical activity) to provide a time lag to allow filling of the left ventricle.

A short interval can cause or be atrial fibrilation or very fast atrial contractions. A short interval finding with EKG should be correlated to clinical observations and history for arrythmia. There is a linear inverse relationship of a short interval PR and heart rate. If there is a fast heart rate due to stress, etc. there would be an expectation of a shorter PR interval. A respiratory condition and medication, etc. can abnormally increase heart rate and lower the PR interval. That could be an explanation if there is no history, etc. for arrhythmia.

My heart rate was around 115 resting with mild edema. Faster heart rate to compensate for less oxygen with each heart beat...shorter PR interval.

flowergirl2day · 08-03-2007, 12:25 PM

Many thanks for your informative post. You suggested the effect of my meds as a likely cause. I have been having problems with them lately. My HR is fast even now. With some justified reservations about the CCBs, I had to restart this drug at 1/2 my normal dose. No further swelling so far. Another possible cause for the drop in PR interval you mentioned, respiratory difficulties, is also present. As you suggest, a respiratory condition along with the meds can increase the heart rate, which then results in the decrease of the PR interval. In this context it makes perfect sense. Much appreciated, Kenkeith.

Flowergirl