Atrial Fibrillation (AFib) Support Group
Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). Heart beats in a normal heart begin after electricity generated in the atria by the sinoatrial node spread through the heart and cause contraction of the heart muscle and pumping of blood.

One of the research centers for afib (Valley Hospital, Ridgewood, NJ) is only 5 miles from my home, but I'm not ready for an abalation yet. Periodically, I think about rhythm control. Then the episode stops and that idea seems less important.
Seriously, that is quite a story. You look like you are in great shape (from what is in the picture). 1 hour isn't too bad. I guess if your EP is aware of the increase, watching and waiting might be the best idea. You sound like the athlete healthy heart version of afib. I guess you know all about the vagal tone thing.
petey
"Possible mechanism of atrial fibrillation in
sportsmen
In sportsmen one may identify two factors that have
been clearly demonstrated to favor the occurrence of
atrial fibrillation: an increased vagal tone with bradycardia,
and a slight dilatation of the heart cavities.
We have observed such an enlargement of cardiac
cavities and left ventricular mass in our patients when
compared with healthy controls. Whether or not these
changes are due to chronic sport practice cannot be
established in our study. This apparent relationship
between prolonged sport practice and atrial fibrillation
had not been previously well established, perhaps
because cardiovascular evaluation in athletes is usually
performed at the time of maximal sport activity.
Our sportsmen were evaluated after many years of sport
practice, when some of them had already reduced their
activities to a very low level. Only after specifically
asking for their past sport activity did it become apparent
that these patients had been performing vigorous
exercise for many years. It is well known that the
incidence of atrial fibrillation increases with age. In our
patients, the risk factor of sport activity may have had
many years of exposure, as it occurs with other risk
factors, such as hypertension, leading to the appearance
of the arrhythmia."
That is a quote.
petey
Vagal tone is the degree of activity occurring within the parasympathetic nervous system, resulting in changes to the heart rate and other key functions. The vagus nerve, among many other things, inhibits the heart beat to keep the organ beating within a safe range. When the vagal tone increases or decreases, a patient will experience changes in heart rate, and these can sometimes become dangerous or even fatal.
When activity increases, patients experience bradycardia, where the heart slows down, because the inhibitory effect of the vagus nerve is stronger. Patients with decreased tone will develop tachycardia, a fast heart rate, because the nerve is not acting to suppress activity within the heart. This can be the result of a temporary situation, or a long term health problem. Sometimes, changes are not necessarily a sign of disease. Athletes, for example, have a higher vagal tone, and as a result will have a slow resting heart rate."
BTW, I see your birthday is coming up soon. 65. Hope you got your Medicare stuff in. Happy Birthday.