My few readers--the ones I know of because they email me or speak to me directly--complain that I only post when I am complaining about my immanent demise. Of course, the whole idea of this blog originally (2011!) was to simplify my cancer experience to a single communication. And, it just evolved from there--but not very far--because I have had maybe a tad more than the normal difficulty of ageing gracefully. I am very thankful that I continue to age, given the alternative.
Today, I report on a followup to a procedure I had done a month ago. At that time, I believe I reported that I had a number of days in a row where my heart rate was constantly at 135 bpm or above. My iwatch won't do an ECG when the HR is above 120, so I had to guess that I was in a-fib or a-flutter during this period. I was unable to reduce the rate with anything I tried. The rhythm people at IMC suggested I come for a cardio-version which is the application of shock to the heart in order to get back into sinus rhythm. It was an out-patient procedure and it fixed me up just fine, as they say.
I have had no high heart rate since the procedure, and I was able to resume my former activity levels right away. Since then, I have monitored my heart rhythm by doing a daily ECG via the iwatch. I have only occasionally been graced with the conclusion "Sinus Rhythm". Almost all of the outcomes are "Inconclusive", to which the watch says to wit: if this outcome continues, see your heart guy. So, I was interested in what a full 12-lead ECG would show, since that is the first and usually the only thing they do other than vitals.
I had taken a reading at home before the appointment and got an Inconclusive. The 12-lead ECG was normal and the discussion with the PA was very informative. I am getting some extra heart beats, perhaps a ventricular contraction to get in sync with the auricle which has already beaten. These are really common and not of concern. In a signal detection analysis these extra beats would be considered noise, rather than signals, the signal being the sinus wave. I can see the extra beats strewn among the sinus waves on my iwatch. If there are several of them in the 30-sec sample then the watch concludes: "Inconclusive". If there are none or very few it will conclude: "Sinus Rhythm". Again, in signal detection terms, the Inconclusive conclusion could be considered a false negative. The iwatch is very conservative on this. If y'all know anything about signal detection (or inferential statistics for that matter) you will know that the cutoffs (ie criteria) for these inferences can be changed by external contingencies.
Well enough of that in-the-weeds stuff. Really all I have to do now is reset my own criteria. If I see enough sine waves in a 30-sec sample on the watch and I otherwise feel well (eg no rapid HR) then things are cool whether the watch says Inconclusive or not.
And that is where we are: things are cool.
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