Max Heart Rate not returning to expected rate after cessation of Flecainide

Male 57, Exercise Induced PVCs 1999-2005, Full Time PVCs, 2006-2010.  14,000 per 24 hours.  Controlled by Flecainide.  Max heart rate in 2005 was 176, in 2006 after starting Flecainide was 150.  Stopped taking Flecainide 6 weeks ago.  No PVCs 98% of time.  Max heart rate now 160.  In 2005 I was a very good runner.  In 2006-2010 I was just average runner.  Why hasn't heart rate returned to 170 range?

[itdood]

max heart rate declines as we age.  163 is your predicted max.  You are bumping up against the max, I see no problems.

It does look like flec had some affect on your max rate.  You've aged 5 years since your comparison.  Whether you took flec or not your max heart rate was going to come down.  Couple that with your lowered training level and you could account for the drop.

Back in '05 when you were hitting 176 you were about 8 bpm over predicted max.  You are now 3 under predicted max.

Are you hell bent on training at a hyper level?  If you are you should give that a second thought.  Hyper training athletes tend to have  a higher incidence of arrhythmia, in particular, a-fib as they age.  The incidence of a-fib is something like 20% higher for highly conditioned athletes as they age compared to the general population, if i recall correctly.    What this tells me is that the stress on the heart may have benefits for CAD but it has negative impact on rhythm.  Everything in moderation as they say.

[parkrunner]

My maximum heart rate should not decline by 16 bpm in just 5 years.  I've never been average.  My max bpm has always been 5 to 8 bpm higher than the "catch-all" 220 minus age except while taking Flecainide.  Even when I was 16 my max rate was 215.