Today’s indoor rowing session was a deliberately conservative 10K. It was 10K, because that’s the minimum distance I can row in a day for one of the two current Concept 2 challenges in which I’m participating. It was a laid-back pace, because I’m looking for confirmation that all negatively influential traces of the intravenous chemicals (received during the cardio PET scan on March 12) are completely flushed-out.
The session went well, so perhaps they are.
If you are wondering what the title reference to “sleeping heart trail” is about, that is mentioned, along with relevant images, below the screenshots of today’s rowing results. (It mainly has to do with a sleeping-heart rhythm graph the likes of which I’d never seen before and which I’m guessing was due to the after-effect influence of one or more of the injected compounds received during the cardio PET scan. )
Today’s 10K was done with some non-periodic variations in pace. It was uploaded to YouTube as a screen recording and is available at the following link: “Indoor Rowing 10K with variations 03172018“.
Now, for the Sleeping-Heart Trail part:
Below are graphs of heart rate samples taken during the nine most recent nights of sleep, before and after the cardio PET scan which was done the afternoon of March 12th. During the scan, there was first an injection of radioactive isotope solution, to highlight the heart, whose normal behavior was the focus of the first scan. That first scan lasted 14 minutes according to the technician.
After the first scan, there was an injection which was mainly if not exclusively a solution containing regadenoson. The effect of that second injection was to greatly dilate blood vessels and thereby cause the heart to beat faster in order to compensate for the corresponding reduction in blood pressure. The regadenosone effect was definitely noticeable but lasted only for about 3 minutes.
As another side effect, it cause my rate of respiration to increase, though breathing remained very shallow, as though I was almost not breathing except for the slight increase in frequency of the chest slightly expanding and contracting more than it had been before the injection.
An additional side effect was that near the end of the 3 minutes I could feel a light degree of perspiration as though all my skin which was directly exposed to the air had been dampened with a moist cloth.
The single most noticeable side effect during the three minutes was that I felt agitated and restless and had a strong urge to get off the horizontal platform and pace around the room, instead of laying still. I remained motionless by an act of will to resist that urge.
But… three nights later the sleeping heart graph was something I’ve never ever seen before: It was totally flat for the entire night, except once when it was abnormally high. Normally, my heart rate varies slightly during the night and either gradually tapers down to an overall slower BPM or gradually tapers up, from the beginning to the end of the total recorded sleep period. In other words, the heart rate graph during a night’s sleep usually has an average slope either up or down from beginning to end.
I suspect the abnormally straight-line regularity had something to do with the regadenoson, since it is the only chemical of which I’m aware which is directly related to heart behavior and which was included in the injections during the scan.
While rowing the next day after the ultra-regular all-night heart rhythm, I experienced one of the most irregular and excessively-high heart rhythm and BPM episodes of any ever experienced during an erg session. (See the post titled Revisiting Rowing Through A Heart Attack.)
Also on the night of the 14th-15th which is graphed above, there was an “elevated heart rate” notification from the Apple Watch for that night:
Another thought is, that whether or not the unusual heart behavior recently was due to the lingering presence of one or more of the injected chemicals, it may have been also related to the heart’s recovery from whatever it was that it experienced during the chemical stress test.
Happy and heart healthy rowing to you.