#EPeeps Are you looking for something to do while visitags turn red?

Here’s an idea+it even involves looking at much beloved squiggly lines: transmural RF effect in vivo!

Pic: LAPW 1st site
GA, Agilis, CS pacing 600ms, 5ml/kg IPPV
2mm stability, CF 100% min 1g, ACCURESP off.

Pic: corresponding CARTOREPLAY EGMs at RF onset (see red line indicating annotation start at the bottom)

Top to bottom:

BS ECG
MAP1-2 bipole 1.33 mV scale
MAP1 unipolar EGM 3.45mV scale clearly RS morphology
CS pacing

Don’t worry, it’s about to get exciting #EPeeps

Just over 4s into this 25W application (remember, lower power at left-sided LAPW sites), final unipolar EGM morphology clearly changes to pure R.
Ok, ~5% of cases have artifact making the exact timing of first transmural transition less clear, but honestly, it’s usually as shown.

To prove this wasn’t a fluke, this was the first of 3 consecutive (and thereafter to the end of RF at this site) pure R EGMs.

Q: Could this be of value to you, or are you happier with tag colour change?

Interesting here to reflect on the work of a pioneer in the field of practical application of unipolar EGM morphology change during PVI - Agustín Bortone. Using 30W and at pure R+5s, *all* atrial lesions were transmural.
Q: true, or too good to be true?!
https://www.ncbi.nlm.nih.gov/m/pubmed/26092576/

What’s that? You want proof that this first site I ablated demonstrated pure R change from then on?

I can go one better.

Here’s transition to tag 2: abrupt motion->2nd “stability site” annotation w/o “lost” RF, 4.5mm away (pic 1), with pics2+3 showing immediate+ongoing pure R

The R-sided sites are really cool but I’m worried many will have disengaged, still thinking I’m making this all up. I’ll post these if anyone’s interested.

Meanwhile, final Q: are you happy watching colour change alone, or could you+your patients gain from observing physiology?