Radiofrequency ablation lesions in low-, intermediate-, and normal-voltage myocardium: an in vivo study in a porcine heart model

TY - JOUR

T1 - Radiofrequency ablation lesions in low-, intermediate-, and normal-voltage myocardium

T2 - an in vivo study in a porcine heart model

AU - Tofig, Bawer J

AU - Lukac, Peter

AU - Nielsen, Jan M

AU - Hansen, Esben S S

AU - Tougaard, Rasmus S

AU - Jensen, Henrik K

AU - Nielsen, Jens C

AU - Kristiansen, Steen B

N1 - Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: [email protected].

PY - 2019/12

Y1 - 2019/12

N2 - AIMS: Contact force (CF) between radiofrequency (RF) ablation catheter and myocardium and ablation index (AI) correlates with RF lesion depth and width in normal-voltage (>1.5 mV) myocardium (NVM). We investigate the impact of CF on RF lesion depth and width in low (<0.5 mV) (LVM) and intermediate-voltage (0.5-1.5 mV) myocardium (IVM) following myocardial infarction. Correlation between RF lesion depth and width evaluated by native contrast magnetic resonance imaging (ncMRI) and gross anatomical evaluation was investigated.METHODS AND RESULTS: Twelve weeks after myocardial infarction, 10 pigs underwent electroanatomical mapping and endocardial RF ablations were deployed in NVM, IVM, and LVM myocardium. In vivo ncMRI was performed before the heart was excised and subjected to gross anatomical evaluation. Ninety (82%) RF lesions were evaluated. Radiofrequency lesion depth and width were smaller in IVM and LVM compared with NVM (P < 0.001). Radiofrequency lesion depth and width correlated with CF, AI, and impedance drop in NVM (CF and AI P < 0.001) and IVM (CF and AI depths P < 0.001; CF and AI widths P < 0.05). Native contrast magnetic resonance imaging evaluated RF lesion depth and width correlated with gross anatomical depth and width (NVM and IVM P < 0.001; LVM P < 0.05).CONCLUSIONS: Radiofrequency lesions deployed by similar duration, power and CF are smaller in IVM and LVM than in NVM. Radiofrequency lesion depth and width correlated with CF, AI, and impedance drop in NVM and IVM but not in LVM. Native contrast magnetic resonance imaging may be useful to assess RF lesion depth and width in NVM, IVM, and LVM.

AB - AIMS: Contact force (CF) between radiofrequency (RF) ablation catheter and myocardium and ablation index (AI) correlates with RF lesion depth and width in normal-voltage (>1.5 mV) myocardium (NVM). We investigate the impact of CF on RF lesion depth and width in low (<0.5 mV) (LVM) and intermediate-voltage (0.5-1.5 mV) myocardium (IVM) following myocardial infarction. Correlation between RF lesion depth and width evaluated by native contrast magnetic resonance imaging (ncMRI) and gross anatomical evaluation was investigated.METHODS AND RESULTS: Twelve weeks after myocardial infarction, 10 pigs underwent electroanatomical mapping and endocardial RF ablations were deployed in NVM, IVM, and LVM myocardium. In vivo ncMRI was performed before the heart was excised and subjected to gross anatomical evaluation. Ninety (82%) RF lesions were evaluated. Radiofrequency lesion depth and width were smaller in IVM and LVM compared with NVM (P < 0.001). Radiofrequency lesion depth and width correlated with CF, AI, and impedance drop in NVM (CF and AI P < 0.001) and IVM (CF and AI depths P < 0.001; CF and AI widths P < 0.05). Native contrast magnetic resonance imaging evaluated RF lesion depth and width correlated with gross anatomical depth and width (NVM and IVM P < 0.001; LVM P < 0.05).CONCLUSIONS: Radiofrequency lesions deployed by similar duration, power and CF are smaller in IVM and LVM than in NVM. Radiofrequency lesion depth and width correlated with CF, AI, and impedance drop in NVM and IVM but not in LVM. Native contrast magnetic resonance imaging may be useful to assess RF lesion depth and width in NVM, IVM, and LVM.

KW - Ablation index

KW - Contact force

KW - Lesion size

KW - Low-voltage myocardium

KW - Magnetic resonance imaging

KW - RF lesion depth and width

KW - Scar

KW - Ventricular tachycardia

U2 - 10.1093/europace/euz247

DO - 10.1093/europace/euz247

M3 - Journal article

C2 - 31545375

SN - 1099-5129

VL - 21

SP - 1919

EP - 1927

JO - Europace

JF - Europace

IS - 12

ER -