Antitachycardia Pacing (ATP) - How it Works, How to Improve 

I'm not sure about "millions" but thanks so much for the kind words! I'm so excited that these videos have been helpful for people to understand some fundamental principles of EP! I really appreciate your feedback!

I really appreciate your overly-generous words! I don't at all have Josephson's intellect, but at least I'm able to explain things in a teaching style that seems to resonate with those looking to establish (or re-establish) a strong foundation in EP!

Agreed!

Thank you so much for your most generous and kind comments! So glad you found the video helpful!

Glad it was helpful! Thanks for watching!!

Fantastic and thank you! It is so amazing that these videos have found an international audience, and that people have found them instructive and helpful! I appreciate you taking the time to give wonderful feedback!

Thanks so much! It seems this talk hit the intended mark 👍

Thanks so much! I'm thrilled you found this video helpful!

I can't tell you how satisfying it is to hear this type of great feedback from the international community! It really demonstrates the power of social media from an educational standpoint!

Thanks so much! I do like how this one came out - it's an important topic that people don't always think about in detail.

Ha! You are too kind!! Thanks for the vote of confidence! :)

I'm so glad you found this video helpful! I really enjoyed making it, and hope it helps many people better understand the concept and mechanism of anti-tachycardia pacing!

I'm really pleased with how this one came out! I think it helps people understand what ATP is trying to achieve.

Thanks for watching and for taking the time to give nice feedback!!

@@dr.joshuacooper-arrhythmia9917 Dear Prof. Cooper: I really learned the concepts of electrophysiology with your talks.

Oh my gosh, it is a spooky coincidence that you should ask this question. Literally two days ago I used surgical temporary epicardial wires to pace terminate an atrial flutter in our ICU. And then I was called last night by the ICU team because the patient went back into atrial flutter and they wanted instructions on how to do what I had done the previous day, which is basically your exact question. I think it has been a few years since I have used a temporary pacing system to do antitachycardia pacing, and here it happens to coincidently come up twice within 24 hours! Different pacing systems operate differently. We were using the Medtronic temporary pacing box, which has a rapid atrial pacing option in the menu on the bottom part of the screen, and one has to toggle between different menu functions in order to find this pacing option.

Thanks so much! Glad you enjoyed it! :)

Great question! In this algorithm, the S2 coupling interval is progressively shortened, so when S2 hits refractoriness, that implies that longer intervals had already failed (presumably because the S2 beat did not successfully propagate to the circuit and inter the excitable gap at the right place). And so, S2 needs to be prolonged again in order to capture, but that will likely be insufficient for VT termination without also adding an S3. And of note, the S2 beat will "prime" the interposed myocardial tissue by shortening its refractory period, thereby allowing an even shorter S3 coupling interval to capture and propagate to a greater degree than S2 was able.

@@dr.joshuacooper-arrhythmia9917 Thanks for the explanation!

Thank you so much for your comments and interest! It is not possible to manually program any random device to this scheme, as standard anti-tachycardia pacing has very specific programming options including burst pacing and ramp pacing but no option for s1s2 programming. With respect to the post-pacing interval, that refers to the time between the last paced beat and the first return sensed beat after that if tachycardia is ongoing. Please refer to my video on entrainment which goes into this concept in detail and I think you will find it extremely helpful!

@@dr.joshuacooper-arrhythmia9917 thank you very much! for both the video and your reply!

Yes indeed, ATP principles also apply to atrial reentrant arrhythmias! In fact, atrial ATP can be programmed in certain pacemakers and defibrillators. The main differences with atrial reentry include the size of the atrial flutter circuit (often large, occupying much of the chamber), the size of the excitable gap (often large), and the paucity of scar barriers in atrial reentry that are highly present in reentrant VT (often including the presence of a protected VT isthmus, embedded within a region of scar).

@@dr.joshuacooper-arrhythmia9917 thank you Dr Cooper for your prompt reply. Your video explanation makes it really easy to understand.