Sorry should add, 45 year old male pretty good lifestyle pretty active don't drink don't smoke.

Okay, welcome to the forum and I've read your posting and concerns.

Episodic atrial fibrillation is a common manifestation in otherwise healthy individuals and does not necessarily represent a clinical sign of cardiopathology. Indeed, your test results support entirely normal heart function and structural soundness. It is not uncommon for the presentation to arise nocturnally as well and unless sleep apnea is present, then the no underlying cause is to be considered.

The "thump" sensations are actually nothing more than benign vagus nerve-induced palpitations and originate from outside the heart by wayward stimulation of the vagus nerve as a consequence of stress or anxiety. You can more think of the events as a muscle twitch similar to that you might experience with an eyelid from time to time. Remember that the heart is as much a muscle as it is an organ and because it is so dynamic, any irregular nerve impulse being introduced into the cardiac cycle can be variable in sensation depending upon precisely when the signal intervenes i.e. atrial or ventricular.

The reason that the events compel a cough reflex is because the vagus nerve innervates many organs and structures in the body, including the larynx. When inappropriate evoked potentials, or nerve impulses travel along the vagus nerve, all of the terminal endings respond. Again, the heart's response is merely more dramatic because of its dynamic nature. The cough is induced by the same nerve impulse.

The events are incapable of causing you any harm and lack the capacity to induce any type of cardiac event whatsoever. Although they produce a strange sensation which is variable in presentation, they are nevertheless entirely benign and pass without subsequent effect.

You'll be just fine.

Best regards,

Rutheford Rane, MD (ret.)