Walking and pondering

The backlots of McMasters Beach on this morning's walk.

I walked about 10km this morning in misty, drizzly, and almost autumnal weather along some less-travelled roads and trails around nearby McMasters Beach.  Walking gives more time to look at your surroundings, and I've enjoyed a closer examination of the forests and properties that I often pass more cursorily on the run.  It's all relative, of course, with walking better than running, and running better than biking, if you want to absorb your environment.  All are better than driving.

The gravestone of Allan McMaster, the first European
settler in the area named after him.

Another advantage of walking, for me at least, is that it is the best time for thinking.  I'm a stroller rather than a power walker, and the gentle perambulation seems to stimulate my analytical brain cells.  As I walked this morning, experiencing no breathlessness or heart palpitations, I wondered about the chances that my heart problems were behind me.  If not, how would the return of the Atrial Flutter (AFl) be triggered?  By running too hard?  And if it was triggered, would it suddenly be as debilitating as it was before the Cardioversion, or would the onset be slower?  What were the chances of reversion, and what were the risk factors?  Wouldn't the cells through which my heart was passing the errant electrical pulses still be there, just a dormant pathway waiting to be reactivated by stress or some other trigger?

Umbrellas were optional on a drizzly morning walk.

There was lots to think about, inconclusively, and I returned home to do some more Googling.  Nothing I could find gave me more certainty, but there were clues.  One study in particular, of men a similar age to me, found that 55% had recurrent AFl within six months of their Cardioversions.  Underlying heart disease, previous episodes of AFl, and enlarged left atriums all seemed to be statistically significant factors in those who reverted.  I'm not conscious of previous AFl events, and my cardiologist found no evidence of heart disease, but he did find "mild Left Atrial dilatation".

Cockrone Lagoon on an autumnal morning.

Other studies have found enlarged left atrial size to be more common in long-term endurance athletes, than others of a similar demographic, and that this seemed to be associated with great incidence of Atrial Fibrillation (AF) and AFl.  So, it seems reasonable to assume I remain at significant risk of reversion.  The great unknown for me, though, is whether the enlarged left atrium was the key factor in the development of my AFl, or was it the Pulmonary Embolism (PE) placing undue pressure on the heart's function that was the trigger.  Although I'm probably stuck with the enlarged left atrium, the PE should be gone soon, if not already.  Does that mean there's a good chance I won't have the problem again?  Probably not, but only time will tell, although there will never be a point at which I can say there is no further risk.