Background: Several authors investigated the propagation of the atrial impulse inside the Kock’s Triangle (KT) during sinus rhythm (SR) and tachycardia. However, a thorough knowledge of the origin and significance of multicomponent potentials referred to as slow pathway (SP) potentials, is still lacking. Purpose: Purpose of the present study was to evaluate the conduction velocities (CVs), signal characterization and find out the origin, distribution, and timing of the SP potentials recorded in the KT. Methods: The 3-D KT geometry was created during both SR and tachycardia from the basket mapping catheter and a m apping System. The KT was divided into eight distinct regions moving from an antero-septal to postero-septal areas and bounded by tricuspid annulus (TA) anteriorly and tendon of Todaro (TT) posteriorly. The fast pathway (FP) and the SP were localized. Each area was characterized in terms of distribution and timing of Jackman (JP) and Haissaguerre (HP) potentials, CV and signal amplitude. Results: 20 consecutive successful SP ablation cases of AVNRT were included. The mean number of acquired points of RA was 6000±1100 (mean RA mapping time=12±5 minutes); 275±63 points were acquired inside the KT over a mean KT area of 29±3 mm2. Both JPs and HPs were detected in 100% of pts during SR, whereas they were less frequently recorded during tachycardia (90% and 95%, respectively). The mid-septal regions bounded by TA anteriorly and TT posteriorly showed higher prevalence of JP as compared to antero-/mid-septal regions across TT both in SR and tachycardia (77.4% vs 4.8% during SR, p<0.0001; 84.1% vs 0% during tachycardia, p<0.0001, respectively). HPs seemed to have variable distribution across KT (50% of these potentials recorded in antero- to mid-septal regions across TT for SR, 52.3% for tachycardia). The median signal voltage was 0.44[0.2-0.9] mV during SR and 0.5[0.22-0.895] mV during tachycardia. The mid-septal region was the area of lowest voltage compared to other regions (0.2[0.1-0.7] mV vs 0.5[0.4-1.5] mV for SR, p<0.0001; 0.2[0.15-0.6] mV vs 0.6[0.4-1.5] mV for tachycardia, p<0.0001, respectively) and it had a mean voltage lower than 50% of mean voltage of KT in 81% of the cases for RS and 86% for tachycardia. The mean CV was 0.45±0.2 m/s during SR and 0.46±0.2 m/s during tachycardia. The mid-septal region was the area of mean lowest CV compared to other regions (0.33±0.1 m/s vs 0.5±0.2 m/s for RS, p<0.0001; 0.35±0.1 m/s vs 0.5±0.2 m/s for tachycardia, p<0.0001, respectively). Conclusions: The genesis of the JPs, although not perfectly known, might be explained by wavefront collision in the lowest area of the KT that may generate a low-high-type double potential. These potentials seem to be associated with slow conduction areas and low signal-amplitude areas, whereas HPs seem to have variable distribution across KT.
Characterization of multi-component potentials inside the Kock's Triangle with ultra-high density mapping system
L. Segreti;MG. Bongiorni;F. Piccolo;
2019-01-01
Abstract
Background: Several authors investigated the propagation of the atrial impulse inside the Kock’s Triangle (KT) during sinus rhythm (SR) and tachycardia. However, a thorough knowledge of the origin and significance of multicomponent potentials referred to as slow pathway (SP) potentials, is still lacking. Purpose: Purpose of the present study was to evaluate the conduction velocities (CVs), signal characterization and find out the origin, distribution, and timing of the SP potentials recorded in the KT. Methods: The 3-D KT geometry was created during both SR and tachycardia from the basket mapping catheter and a m apping System. The KT was divided into eight distinct regions moving from an antero-septal to postero-septal areas and bounded by tricuspid annulus (TA) anteriorly and tendon of Todaro (TT) posteriorly. The fast pathway (FP) and the SP were localized. Each area was characterized in terms of distribution and timing of Jackman (JP) and Haissaguerre (HP) potentials, CV and signal amplitude. Results: 20 consecutive successful SP ablation cases of AVNRT were included. The mean number of acquired points of RA was 6000±1100 (mean RA mapping time=12±5 minutes); 275±63 points were acquired inside the KT over a mean KT area of 29±3 mm2. Both JPs and HPs were detected in 100% of pts during SR, whereas they were less frequently recorded during tachycardia (90% and 95%, respectively). The mid-septal regions bounded by TA anteriorly and TT posteriorly showed higher prevalence of JP as compared to antero-/mid-septal regions across TT both in SR and tachycardia (77.4% vs 4.8% during SR, p<0.0001; 84.1% vs 0% during tachycardia, p<0.0001, respectively). HPs seemed to have variable distribution across KT (50% of these potentials recorded in antero- to mid-septal regions across TT for SR, 52.3% for tachycardia). The median signal voltage was 0.44[0.2-0.9] mV during SR and 0.5[0.22-0.895] mV during tachycardia. The mid-septal region was the area of lowest voltage compared to other regions (0.2[0.1-0.7] mV vs 0.5[0.4-1.5] mV for SR, p<0.0001; 0.2[0.15-0.6] mV vs 0.6[0.4-1.5] mV for tachycardia, p<0.0001, respectively) and it had a mean voltage lower than 50% of mean voltage of KT in 81% of the cases for RS and 86% for tachycardia. The mean CV was 0.45±0.2 m/s during SR and 0.46±0.2 m/s during tachycardia. The mid-septal region was the area of mean lowest CV compared to other regions (0.33±0.1 m/s vs 0.5±0.2 m/s for RS, p<0.0001; 0.35±0.1 m/s vs 0.5±0.2 m/s for tachycardia, p<0.0001, respectively). Conclusions: The genesis of the JPs, although not perfectly known, might be explained by wavefront collision in the lowest area of the KT that may generate a low-high-type double potential. These potentials seem to be associated with slow conduction areas and low signal-amplitude areas, whereas HPs seem to have variable distribution across KT.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
