Usefulness of entrainment mapping using the activation sequence of the last captured excitation in complex dual‐loop atrial tachycardia

Abstract

The PPI is obtained from the pacing site only, but the last captured beat could be obtained from all electrodes. It is advantageous to use the information from all available electrode recordings to determine the dynamic relation between complex dual-loop reentrant circuits.

Is proximal coronary sinus involved in the circuit in some cases of ECG “typical” atrial flutter?

“…A point in common, among these studies, is the presence of fragmented low‐voltage APs variably and extensively located between septal CTI, CS ostium, and proximal CS (all sites within the circuit at entrainment maneuvers at RF successful sites). Fibrosis due to age, structural HD, previous CTI RF ablation, and LA enlargement appears to favor these AFLs. In our patients, fibrosis of the mid‐IAS could explain why activation front emerging from CTI enters the proximal CS instead of IAS, maybe involving CS‐LA connections, and emergs in the RA using other connections than CS.…”

“…A diseased or enlarged LA or iatrogenic post‐RF LA scarred zones might play a role in the genesis of some AFL . CTI‐dependent RA AFL is quite common after RF ablation for AF.…”

“…The ensemble of these reports is not homogeneous [19][20][21][22][23][24][30][31][32][33][34] and various re-entry patterns can be conceived in these "CS AFLs." The Eustachian ridge is not a fixed barrier, permitting a circuit re-entry in a dissociated CTI.…”

“…Some authors described, or at least suggested, a proximal CS and maybe left atrium (LA) involvement in the circuit of some cases of typical AFL or iatrogenic recurrent AFL after successful CTI radiofrequency (RF) ablation, implying a nonexclusive CTI location of a part of the circuit. Globally, these AFLs are considered episodic or very uncommon.…”

“…Anisotropic conduction [16][17][18] due to cross-over and interlacing trabeculae at this site could occur in this area and leads to a conduction delay of the lower CTI septum and maybe of the CS close to it. Some authors described, or at least suggested, a proximal CS and maybe left atrium (LA) involvement in the circuit of some cases of typical AFL or iatrogenic recurrent AFL after successful CTI radiofrequency (RF) ablation, [19][20][21][22][23] implying a nonexclusive CTI location of a part of the circuit. Globally, these AFLs are considered episodic or very uncommon.…”