PVCs and Cold Weather Excercise

[KankRat]

Greetings.
I am a 42 year old runner and cyclist.  In winter I get PVCs severe enough that I feel faint if I get up fast enough.  I would call the palpitations pretty severe.  My resting pulse is already pretty low (high 30's)  When the skipped beats (or extra...whatever) start I really feel like ****.  I feel like someone is sitting on my chest.  And when they stop, sometimes suddenly, I feel like I'm drowning in oxygen.  Almost high. I can suppress them by running and sometimes they totally clear up afterwards.
The PVCs can last as long as 24 hours and longer.  The main thing I can see that triggers them is sustaining my heart rate at over 80% during winter.  I really only get them, the severe runs of PVCs in winter.
Caffein does not seem to trigger them, but defintley don't help.  I try to keep it down to one cup of coffee a day, but usually have several cups of green tea afterwards.  I drink red wine regularly but can't pin a connection down since I typically give up booze and caffein for Lent and still feel like **** unless it gets warm out for a good length of time.
I'm no where near dehydrated.  I pay attention to that and try to keep my urine the color of lemonade.
In 07 I had a 6 hour or so episode after a duathlon in June, In which I sustained 170bpm for an hour and a half ( my max is 185 bike, 188 running) and won 3rd in my age group.   Other than that, I felt great for months, in which time I rode my bike 3000 miles and trained for and ran the infamous '07 Chicago Marathon (3:31 in temps approaching 90F) with not a hint of a problem.
I've been thru a gammut of tests including a 64 slice scan. My electrophysiologist recommends I just live with it.  He has given his blessing to my endurence fun (though I doubt that he knows how hard I go).
The drugs were worthless.  This winter I've been doing only enough to keep from getting fat.  Staying on a treadmill or indoor bike trainer in <45F.  I feel occasonal PVCs.  But not too bad.  I wear an HRM and keep it pegged at <78% MHR.
the last thing I should mention is I'm an ex-fat smoker.  Quite smoking in '95. Dropped 50lbs in 04.
10,000 on the bike. 2 half marathons, 1 full marathon since.
I'm learning to live with this.  But just curious.  Anybody else have similar reactions to cold?
Mine are repeatable.  I have extreme tolerance to heat, my endurence buddies call me "the Reptile", but cold kicks my ***.

So Any feedback appreciated...

[sueinns]

Everyone appears to have certain triggers that are unique to them.  I ran this morning and it was minus 25 - felt fine except for some really cold toes.

Your body has to work harder to keep itself warm during the winter.  If you add that to working out at 80% (pretty intense), maybe it's just that extra bit needed to bring on the PVC's.

You had a 6 hr episode in June during a race in which you would have definitely pushed yourself.  A marathon, while very tough (speaking from experience), isn't a sprint so your heart wouldn't be at 80% for 3.5 hours.  

Maybe on cold days just stick to the treadmill or don't work so hard when you are outside.  I know, boring but at least it's an alternative.

[KankRat]

Holy Cow! I've been "bleeped" I only used the "C" word used to describe feces and the "A " word used to describe a donkey or "me bumm".  ;-)