Feasibility of late gadolinium enhancement magnetic resonance imaging to detect ablation lesion gaps in patients undergoing cryoballoon ablation of paroxysmal atrial fibrillation

Figure 1. Representative case of electrical gaps in the second ablation procedure accurately predicted on LGE‐MRI (patient number 3). A and B, The overlaid images of the three‐dimensional reconstructed LGE‐MRI and magnetic resonance angiography in the right lateral (A), and cranial (B) views. The site of late gadolinium enhancement is shown as the blue area. There are gaps in the lesion set at the bottom of the right inferior PV, posterior side of the right superior PV, and roof of the right and left superior PVs (arrows). C and D, The electrical gaps to be ablated in the second ablation procedure on the EAM. There are gaps on the posterior side and roof of the right superior PV and roof of the left superior PV (red and green points), and the location of those gaps is well matched to that on the LGE‐MRI. The gap in the LGE‐MRI on the bottom of the right inferior PV does not correlate with the electrical gap in the second procedure, which indicates the absence of a cardiac muscular sleeve or a nontransmural lesion. EAM, electroanatomical mapping; LGE‐MRI, late gadolinium enhancement magnetic resonance imaging; PV, pulmonary vein

Figure 2. The case with residual potentials in the antrum region beside the ablated area in the first CB ablation procedure (patient number 1). A and B, The overlaid images of the three‐dimensional reconstructed LGE‐MRI and magnetic resonance angiography in the right lateral view (A), and anterior‐posterior view (B). The site of late gadolinium enhancement is shown as the blue area. There are gaps in the lesion set at the bottom of the right inferior PV, carina region of the right PVs, and anterior side of the right superior PV (arrows). C and D, The electrical gaps to be ablated in the second ablation procedure on the EAM. There are gaps on the bottom of the right inferior PV, carina region of the right PVs, and anterior side of the right superior PV (red and yellow points), and the location of those gaps is well matched to that in the LGE‐MRI. There are residual potentials to be ablated at the antrum of the left PVs beside the isolation line (red circle). CB, cryothermal balloon; EAM, electroanatomical mapping; LGE‐MRI, late gadolinium enhancement magnetic resonance imaging; PV, pulmonary vein

Figure 3. Distribution of the gaps on LGE‐MRI and the gaps in the second ablation procedure. The unilateral PV antrum is divided into 7 regions—the roof, anterior side, posterior side of the superior PVs, carina region, and the anterior side, posterior side, and bottom of the inferior PVs. There were 12 electrical gaps in the second procedure accurately predicted on LGE‐MRI (red circle). Only 1 gap on the anterior side of the right superior PV was not predicted on the LGE‐MRI (green triangle). There were 3 gaps detected only on the LGE‐MRI without any correlation to the electrical reconnections of the PV, which indicates the absence of a cardiac muscular sleeve or nontransmural lesions (blue triangle). LGE‐MRI, late gadolinium enhancement magnetic resonance imaging; PV, pulmonary vein.