Franziska Fochler1,2, Takanori Yamaguchi1,3, Mobin Kheirkahan1, Eugene G Kholmovski1,4, Alan K Morris1, Nassir F Marrouche1. 1. Comprehensive Arrhythmia Research and Management Center, University of Utah, Salt Lake City (F.F., T.Y., M.K., E.G.K., A.K.M., N.F.M.). 2. Clinic for Electrophysiology, Heart Center Bad Neustadt, Bad Neustadt/Saale, Germany (F.F.). 3. Department of Cardiovascular Medicine, Saga University, Japan (T.Y.). 4. Department of Radiology and Imaging Sciences, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City (E.G.K.).
Abstract
BACKGROUND: Macroreentrant atrial tachycardia (AT) accounts for 40% to 60% of recurrent atrial arrhythmias after atrial fibrillation (AF) ablation. To describe late gadolinium enhancement magnetic resonance imaging (LGE-MRI)-detected scar-based dechanneling as new ablation strategy to treat ATs after AF ablation. METHODS: Data from 102 patients who underwent initial AF ablation and repeat ablation for recurrent atrial arrhythmia within 1-year follow-up were analyzed. All patients underwent LGE-MRI before initial and repeat ablation. Depending on the recurrent rhythm, patients with AF and AT recurrence were assigned to group 1 or 2, respectively. Group 1 underwent fibrosis homogenization as second procedure. Group 2 underwent LGE-MRI-detected scar-based dechanneling. Both groups underwent reisolation of pulmonary veins if necessary. RESULTS: Forty-six patients (45%) presented with AF, and 56 patients (55%) presented with AT recurrence during follow-up after initial ablation. In the first 25 patients from group 2, the AT was electroanatomically mapped, and a critical isthmus was defined. It was found that those isthmi were located in the regions with nontransmural scarring detected by LGE-MRI. In the last 31 patients from group 2, an empirical LGE-MRI-based dechanneling was performed solely based on the LGE-MRI results. During 1-year follow-up after second ablation, 67% patients in group 1 and 64% patients in group 2 were free from recurrence (log-rank, P=1.000). In group 2, 64% in the electroanatomically guided and 65% in the LGE-MRI dechanneling group were free from recurrence (log-rank, P=0.900). CONCLUSIONS: Anatomic targeting of LGE-MRI-detected gaps and superficial atrial scar is feasible and effective to treat recurrent arrhythmias post-AF ablation. Homogenization of existing scar is the appropriate treatment for recurrent AF, whereas dechanneling of existing isthmi seems the right approach for patients recurring with AT.
BACKGROUND: Macroreentrant atrial tachycardia (AT) accounts for 40% to 60% of recurrent atrial arrhythmias after atrial fibrillation (AF) ablation. To describe late gadolinium enhancement magnetic resonance imaging (LGE-MRI)-detected scar-based dechanneling as new ablation strategy to treat ATs after AF ablation. METHODS: Data from 102 patients who underwent initial AF ablation and repeat ablation for recurrent atrial arrhythmia within 1-year follow-up were analyzed. All patients underwent LGE-MRI before initial and repeat ablation. Depending on the recurrent rhythm, patients with AF and AT recurrence were assigned to group 1 or 2, respectively. Group 1 underwent fibrosis homogenization as second procedure. Group 2 underwent LGE-MRI-detected scar-based dechanneling. Both groups underwent reisolation of pulmonary veins if necessary. RESULTS: Forty-six patients (45%) presented with AF, and 56 patients (55%) presented with AT recurrence during follow-up after initial ablation. In the first 25 patients from group 2, the AT was electroanatomically mapped, and a critical isthmus was defined. It was found that those isthmi were located in the regions with nontransmural scarring detected by LGE-MRI. In the last 31 patients from group 2, an empirical LGE-MRI-based dechanneling was performed solely based on the LGE-MRI results. During 1-year follow-up after second ablation, 67% patients in group 1 and 64% patients in group 2 were free from recurrence (log-rank, P=1.000). In group 2, 64% in the electroanatomically guided and 65% in the LGE-MRI dechanneling group were free from recurrence (log-rank, P=0.900). CONCLUSIONS: Anatomic targeting of LGE-MRI-detected gaps and superficial atrial scar is feasible and effective to treat recurrent arrhythmias post-AF ablation. Homogenization of existing scar is the appropriate treatment for recurrent AF, whereas dechanneling of existing isthmi seems the right approach for patients recurring with AT.
Entities:
Keywords:
arrhythmias, cardiac; fibrosis; heart atria; humans; magnetic resonance imaging
Authors: Caroline H Roney; Charles Sillett; John Whitaker; Jose Alonso Solis Lemus; Iain Sim; Irum Kotadia; Mark O'Neill; Steven E Williams; Steven A Niederer Journal: Eur Heart J Cardiovasc Imaging Date: 2021-12-18 Impact factor: 6.875