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What Do You Think 12

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What Do You Think 12

Author

Assoc Prof Harry Mond

Published

February 23, 2026

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84-year old cross-eyed diamond polisher with cataracts.

What do you think?

  • Sinus tachycardia, 100 bpm (arrows).
  • Late ventricular ectopic (red highlight)commencing at the peak of the P wave (blue arrow). Late ectopics, although still premature, are referred to as “end diastolic ventricular ectopics”and often occur with sinus tachycardia.
  • A second end diastolic ventricular ectopic (yellow highlight) occurs within the PR interval (green arrow) and is clearly a fusion beat.
  • A third end diastolic ventricular ectopic(blue highlight) occurs even later in the PR interval (purple arrow) and although a fusion beat, most of the ventricle has already been depolarized via the sinus mechanism.
  • Despite being very late, the ventricular ectopics are “interpolated”, with all the P waves non-concealed, nor are there compensatory pauses.
  • The end diastolic ventricular ectopics are in bigeminy.

 

Sinus tachycardia with bigeminal, interpolated, end diastolic ventricular ectopics infusion.

Here is another example of an end diastolic ventricular ectopic with possible fusion.

Sinus rhythm (red arrows) with an end diastolic ventricular ectopic (red highlight) in the PR interval (red stippled arrow).

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