Inverted P wave

I am a 48 year old male, 160 lbs, in generally good health. I was given an EKG test for heartburn-type pain. The doctor noticed what he called an inverted P wave which was not on the test given when I was 40. He sent me for a stress test, imaging, and echocardiogram. All normal. I was told not to worry, that it might go away or is just the new normal for me.

What exactly is it, and should I ask my doctor before starting up my usual summer exercising program?

[fwilson]

It all depends on which lead the P wave was located in.

Usually, it means your heartbeat did not initiate in the sinus node.

For example, an inverted P wave in Lead II, II, or avF, would usually represent a junctional rhythm.