Thursday, January 31, 2019

ECG Blog #160 (AV Block - AV Dissociation - Isorhythmic)

-----------------------------------------------------------
NOTE: My complete write-up of this case is found on the January 31, 2019 post on Dr. Smith's ECG BlogCLICK HERE — 
-----------------------------------------------------------

The Case: A previously healthy young man presented to the ED for shortness of breath and chest pressure that occurred ~3 hours earlier, when he suddenly felt his heart “skip a beat”, and then begin “racing”. He felt “lightheaded” (presyncopal) during the episode — with the “strong sensation of his heart beating”. He did not feel better until ~45 minutes later. Similar episodes had occurred over the past month — but none lasted as long. Of note, the patient is an active athlete. Figure-1 shows his initial ECG that was obtained in the ED.

P.S. There is a family history of a “junctional or other abnormal rhythm”.

Questions:
  • What is the rhythm in Figure-1?
  • Why is this not “isorhythmic” AV dissociation?
  • Might the fact that this patient’s mother is known “to have a junctional rhythm” have anything to do with this case?
  • Clinically — What would you do for this patient?

Hint:
  • Use of calipers is strongly advised for interpreting the rhythm!

Figure-1: The initial ECG in this case.
-----------------------------------------------------------
NOTE: My complete write-up of this case is found on the January 31, 2019 post on Dr. Smith's ECG Blog — CLICK HERE — 
-----------------------------------------------------------