Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Mar 30;25(3):989-999.
doi: 10.1093/europace/euac257.

Scar conducting channel characterization to predict arrhythmogenicity during ventricular tachycardia ablation

Paula Sanchez-Somonte  1   2   3 , Paz Garre  1   2 , Sara Vázquez-Calvo  1   2 , Levio Quinto  1   2 , Roger Borràs  1   2 , Susanna Prat  1   2 , Jose T Ortiz-Perez  1   2 , Martin Steghöfer  4 , Rosa M Figueras I Ventura  4 , Eduard Guasch  1   2   3 , José Maria Tolosana  1   2   3 , Elena Arbelo  1   2   3 , Josep Brugada  1   2 , Marta Sitges  1   2   3 , Lluís Mont  1   2   3 , Ivo Roca-Luque  1   2   3
Affiliations

Scar conducting channel characterization to predict arrhythmogenicity during ventricular tachycardia ablation

Paula Sanchez-Somonte et al. Europace. .

Abstract

Aims: Heterogeneous tissue channels (HTCs) detected by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) are related to ventricular arrhythmias, but there are few published data about their arrhythmogenic characteristics.

Methods and results: We enrolled 34 consecutive patients with ischaemic and non-ischaemic cardiomyopathy who were referred for ventricular tachycardia (VT) ablation. LGE-CMR was performed prior to ablation, and the HTCs were analyzed. Arrhythmogenic HTCs linked to induced VT were identified during the VT ablation procedure. The characteristics of arrhythmogenic HTCs were compared with those of non-arrhythmogenic HTCs. Three patients were excluded due to low-quality LGE-CMR images. A total of 87 HTCs were identified on LGE-CMR in 31 patients (age:63.8 ± 12.3 years; 96.8% male; left ventricular ejection fraction: 36.1 ± 10.7%). Of the 87 HTCs, only 31 were considered arrhythmogenic because of their relation to a VT isthmus. The HTCs related to a VT isthmus were longer [64.6 ± 49.4 vs. 32.9 ± 26.6 mm; OR: 1.02; 95% CI: (1.01-1.04); P < 0.001] and had greater mass [2.5 ± 2.2 vs. 1.2 ± 1.2 grams; OR: 1.62; 95% CI: (1.18-2.21); P < 0.001], a higher degree of protectedness [26.19 ± 19.2 vs. 10.74 ± 8.4; OR 1.09; 95% CI: (1.04-1.14); P < 0.001], higher transmurality [number of wall layers with CCs: 3.8 ± 2.4 vs. 2.4 ± 2.0; OR: 1.31; 95% CI: (1.07-1.60); P = 0.008] and more ramifications [3.8 ± 2.0 vs. 2.7 ± 1.1; OR: 1.59; 95% CI: (1.15-2.19); P = 0.002] than non-arrhythmogenic HTCs. Multivariate logistic regression analysis revealed that protectedness was the strongest predictor of arrhythmogenicity.

Conclusion: The protectedness of an HTC identified by LGE-CMR is strongly related to its arrhythmogenicity during VT ablation.

Keywords: Ventricular tachycardia; cardiac magnetic resonance; conducting channel; heterogeneous tissue channel; scar.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: I.R.L. and J.M.T. have served as consultants for Boston Scientific and Abbott Medical.L.M. and J.B. report activities as consultants, lecturers, and advisory board members for Abbott Medical, Boston Scientific, Biosense Webster, Medtronic, and Biotronik. They are also shareholders of Galgo Medical, S.L. M.S and R.FV work for ADAS3D Medical S.L. All other authors declare no conflict of interest.

Figures

Graphical Abstract
Graphical Abstract
Figure 1
Figure 1
LGE-CMR reconstruction of the LV with an anterolateral scar in the superior panel (A) and an anteroapical scar in the inferior panel (B). We can distinguish the core and BZ from the healthy myocardium. A line is drawn over the surface representing a conducting channel (A,B). We can see substrate evolution through different layers, from the endocardium (10–30%) to the epicardium (70–90%). LGE-CMR = late gadolinium enhancement cardiac magnetic resonance; LV = left ventricle; BZ = border zone.
Figure 2
Figure 2
Protectedness Panel (A) Protectedness: measure of the length of the protected part (the isthmus) of a corridor. Three examples of HTCs with high protectedness, medium protectedness and low protectedness, respectively. HTC = heterogeneous tissue channel Panel (B) Protectedness computation: HTC centerline surrounded by the area of analysis for protectedness and nearby core and/or healthy tissue The percentages of HTCs that had core tissue, healthy tissue or only border-zone tissue were analyzed within a 3.5 mm distance. Based on these percentages, the local protectedness of the point was determined: If healthy tissue was found anywhere, the local protectedness was set to zero. If no healthy tissue was found, then the percentage of the perimeter that coincided with core tissue determined the local protectedness. Having less than 15% core yielded a local protectedness of 0%, and having more than 40% yielded a local protectedness of 100% (fully protected corridor point). Core values between 15% and 40% (partially protected corridor points) were mapped linearly to local protectedness values between 0% and 100%. Finally, the local protectedness values were integrated over the whole centerline of the corridor, yielding the length of the protected part of the corridor. HTC = heterogeneous tissue channel.
Figure 3
Figure 3
Comparison between the EAM from the VT procedure and LGE-CMR. Panel (A) Left: Activation mapping during VT. Right: LGE-CMR reconstruction of the LV (core, BZ and healthy myocardium are represented). The entire VT cycle length and the diastolic path are located in the anterolateral region of the LV. CMR shows an anterolateral scar and three HTCs (lines). The CC used by the VT on the EAM corresponds to HTC number 2 on CMR, which has a greater BZ mass than the others (5.8 g vs. 1.1 corridor 1 and 0.6 g corridor 3). Panel (B) An example of midmyocardial VT is shown. EAM shows a focal activation pattern with the earliest activation site in the midseptum, with presystolic electrograms. LGE-CMR shows an intramural septal scar (40% layer is shown) with an HTC (line) in the same spot of the earliest activation site. EAM = electroanatomic map. VT = ventricular tachycardia. LGE-CMR = late gadolinium enhancement cardiac magnetic resonance. LV = left ventricle. BZ = border zone. CC = conducting channel. CMR = cardiac magnetic resonance. HTC: heterogenous tissue channel.)
Figure 4
Figure 4
Predictions of the probability of arrhythmogenicity with logistic regression for length, mass, number of ramifications and protectedness.
See this image and copyright information in PMC

References

    1. Wissner E, Stevenson WG, Kuck K-H. Catheter ablation of ventricular tachycardia in ischaemic and non-ischaemic cardiomyopathy: where are we today? A clinical review. Eur Heart J 2012;33:1440–50. - PubMed
    1. Stevenson WG, Khan H, Sager P, Saxon LA, Middlekauff HR, Natterson PDet al. Identification of reentry circuit sites during catheter mapping and radiofrequency ablation of ventricular tachycardia late after myocardial infarction. Circulation 1993;88(4):1647–70. - PubMed
    1. Fitzgerald DM, Friday KJ, Wah JA, Lazzara R, Jackman WM. Electrogram patterns predicting successful catheter ablation of ventricular tachycardia. Circulation 1988;77(4):806–14. - PubMed
    1. Andreu D, Berruezo A, Ortiz-Pérez JT, Silva E, Mont L, Borràs Ret al. Integration of 3D electroanatomic maps and magnetic resonance scar characterization into the navigation system to guide ventricular tachycardia ablation. Circulation: Arrhythmia and Electrophysiology 2011;4(5):674–83. - PubMed
    1. Quinto L, Sanchez-Somonte P, Alarcón F, Garre P, Castillo À, San Antonio Ret al. Ventricular tachycardia burden reduction after substrate ablation: predictors of recurrence. Heart Rhythm 2021;18(6):896–904. - PubMed