Skipped heartbeats that take my breath away, but all my tests are normal...

[MadMax222]

I'm a 34 year old male 6'0 ft 230lbs with high blood pressure and obstructive sleep apnea. Currently I'm on lisinopril 20 mg for the blood pressure and a CPAP alternative for the sleep apnea. Coffee drinker, but trying to cut back. Anyway, here's my story:

For the last several months I've been experiencing episodes of strange heartbeat activity. Every now and then my heart will skip beats after every third or fourth beat and when these skipped beats occur I can feel them literally taking my breath away. Not to the point where I'm keeling over or close to passing out but definitely noticeable. I've had 2 ekgs, an echocardiogram, 2 week holter monitor, and treadmill stress test and none of the results were abnormal. My cholesterol, thyroid, potassium, and magnesium levels are within the normal range as well. This has been an increasingly frustrating and stressful time for me as I'm trying to get into the habit of exercising regularly and making healthy lifestyle changes but these episodes are making me question whether it's safe for me to be working out.

I understand that the occasional skipped heartbeat is more often than not harmless, but what's really concerning me is the slight shortness of breath that accompanies them. Could all these tests be missing something serious? If not then what non heart related issues can possibly be causing this?

[MadMax222]

Forgot to mention I had a chest x-ray that was normal as well