Monday, November 24, 2014

How often do you feel your own heart beating?

I would guess, not very often.

As long as things are working like they're supposed to, most of us can't even feel our heartbeat - unless we are intentionally taking our pulse or something. But most of us won't even do that unless we are monitoring our heart rate during cardiovascular exercise.

I think it's true for most people, and it is definitely true for me, that we become much more aware of our heartbeat when it starts going awry.  Heart palpitations is probably the most common way people become aware of this. Palpitations are common enough.  They can happen as the result of too many stimulants - caffeine, nicotine, speed or cocaine, etc. - or as the result of stress.  So most of us will experience then at one time or another during our adult lives.  Perhaps you have had them already.

I started having palpitations in my 30s - stress and caffeine.  Which is why I have been drinking mostly decaf coffee only for the last 15 years. And also one of the reasons I gave up Pepsi, which I used to drink once or twice a day.  God, I can't even imagine feeling that hyped up on caffeine now. One regular coffee or can of caffeinated soda, and I'm jittery all over for an hour. 

A few years ago, my palpitations were back, but even more alarming to me was that I was unable to do more than 20 minutes of intense cardio exercise in a class setting before I started feeling dizzy or coughing or being completely out of breath.  After a full work-up from my cardiologist, it was determined that there was nothing wrong with my heart.  No damage from chemo in 2008 or radiation in 2002 - and yes, damage from radiation therapy for breast cancer can show up decades later, so that really was something the cardiologist looked for.  Basically, then, there was no identifiable reason why my heart couldn't tolerate an elevated heart rate for more than 20 minutes; it just couldn't.  So... I either had to figure out how to take cardio classes and allow myself to let my heart rate drop more often during class, or I could just manage my cardio - and my heart rate - by exercising as an individual. 

Being an inherently lazy person, I chose the latter.  Which worked fine.  On my own, I never achieve the elevated heart rate that I can hit in an exercise class like kick boxing or Zumba, or even Group Power.  God, Zumba was a killer for me.  I could still do classes like spinning or group power, because it's so much easier to moderate my heart rate in those classes - you can choose your own level of exertion, set your own pace, nobody needs you to keep up with them, and noone is distracted by you if you slow down or hit pause.

So, all of that was manageable.  Did I still have the occasional episode of palpitations? Sure, but who cares. I already knew my heart was fine.

Why am I blogging about this, then?  I'll tell you why. A few months ago, I started noticing a change in the pattern of these palpitation episodes, and that pattern has only become more consistent and persistent. So this Wednesday I am heading back to the cardiologist for a stress echo evaluation.

The pattern goes something like this - first of all, you should know I have an average resting heart rate, somewhere around 72-75 beats per minute. Really, I just checked sitting here at my desk, but it's also all over my medical records. Anyway, here's the pattern: if my heart rate becomes elevated, say, over 88 beats per minute (which is the low end of the target zone for cardio fitness for a woman my age, by the way), it feels like it's racing, and then I start to have palpitations.  These palpitations will persist as long as my heart rate stays up, and then for several minutes afterward, until it settles back down to a resting rate.

The palpitations feel constant, but there is actually a pattern to them.  I had several episodes like this on Saturday, so I took out this stethoscope we have at the house, and I listened in on one of these episodes. I had just been down in the basement dealing with the laundry, and walked upstairs, when I felt the first palpitations. My heart rate was about 85 beats per minute - ba dum ba dum, ba dum ba dum, ba dum ba dum - after about 30 seconds, I had 3 irregular heartbeats - ba dum ba skip, ba dum ba skip, ba dum ba skip. The beat after each skip felt like my heart was flipping over or getting squeezed or something. Then my heart rate slowed down a little to around 80 - another 30 seconds, another 3 irregular heartbeats. Then my heart rate slowed to around 75 - another 30 seconds, another 3 irregular heartbeats. By then, I was back to my resting rate, and I had a full minute without any palpitations.  Then I put the stethoscope away, because noone wants me to obsess about this; that's just too much like my Dad.

So, which kinds of activities bring on these palpitations? Let's see - I walk about 1/2 mile from my car to my office, and then back again, every day; that brings them on.  When I walk up the 3 flights of stairs in my building at work, that brings them on. Or when I walk up a hill. Saturday, when I was rearranging the sunroom to put up the Christmas tree, that brought them on.  Vacuuming, that does it.  It's starting to feel like almost any activity does it. Many of these activities are also starting to cause some shortness of breath. Thus the doctor's appointment.