Hi Donna. Thanks for writing in. I am a qualified and certified cardiologist. I read your mail with diligence. What you have described in pounding from within on your chest is because of volume overloaded ventricle. Usually ectopic beat
(a beat coming too soon after the first) is followed by compensatory pause
during which blood accumulates. This leads to thump in the following beat. If it occurs frequently or distressing, you need to see a doctor who after thorough physical examination may also find some leakage of valve contributing to volume overload. Then a Holter and/or echocardiography
with Doppler examination shall be advised after doing an EKG and chest x-ray. These investigations will establish the exact cause and magnitude of the problem. Usually, here we are dealing with treatable condition so I see no reason to panic yes of course there is cause for concern. Good Luck.
With Best Wishes.
Dr Anil Grover,
MBBS, MD (Internal Medicine) DM (Cardiology)