Division of Cardiovascular Medicine, CARMA Center, University of Utah, Salt Lake City, Utah.
Department of Radiology and Imaging Sciences, UCAIR, University of Utah, Salt Lake City, Utah.
J Cardiovasc Electrophysiol. 2018 Nov;29(11):1556-1562. doi: 10.1111/jce.13709. Epub 2018 Sep 25.
Magnetic resonance imaging (MRI) has been used to visualize radiofrequency (RF) ablation lesions but the relationship between volumes that enhance in acute MRI and the chronic lesion size is unknown.
The main goal was to use noncontrast (native) T1-weighted (T1w) MRI and late gadolinium enhancement (LGE)-MRI to visualize lesions acutely and chronically and correlate the acute area of enhancement with chronic lesion size in histology.
In a canine (n = 9) model RF ablation lesions were created in both ventricles. Native T1w MRI and LGE-MRI were acquired acutely after the ablation procedure. After 8 weeks, another set of RF ablations was performed, and the MRI study was repeated. Volume and depth of enhancement in native T1w MRI and LGE-MRI acquired after the initial ablation procedure were correlated with chronic lesion volume and depth in histology.
Thirty-three lesions were analyzed. Native T1w MRI visualized the acute lesions but not the chronic lesions. LGE-MRI showed both acute and chronic lesions. Acute native T1w MRI volume (average of 102.1 ± 48.5 mm ) and depth (4.9 ± 1.2 mm) correlated well with chronic histological volume (105.9 ± 51.8 mm ) and depth (4.8 ± 1.3 mm) with R of 0.881 (P < 0.001) and 0.874 (P < 0.001), respectively. Acute LGE-MRI had a significantly higher volume of enhancement of 499.7 ± 214.4 mm (P < 0.001) and depth of 7.5 ± 1.8 mm ( P < 0.001) when compared with chronic histological lesion volume and depth.
Native T1w MRI acquired acutely after RF ablation is a good predictor of chronic lesion size. Acute LGE-MRI significantly overestimates the chronic lesion size.
磁共振成像（MRI）已被用于显示射频（RF）消融损伤，但增强的急性 MRI 与慢性损伤大小之间的关系尚不清楚。
主要目标是使用非对比（天然）T1 加权（T1w）MRI 和晚期钆增强（LGE）-MRI 来直观显示急性和慢性损伤，并在组织学上将急性增强区域与慢性损伤大小相关联。
在犬（n=9）模型中，在两个心室中创建 RF 消融损伤。在消融手术后立即获取天然 T1w MRI 和 LGE-MRI。8 周后，再次进行一组 RF 消融，并重复 MRI 研究。将初始消融手术后获得的天然 T1w MRI 和 LGE-MRI 中的增强体积和深度与组织学中的慢性损伤体积和深度相关联。
分析了 33 个损伤。天然 T1w MRI 可显示急性损伤，但不能显示慢性损伤。LGE-MRI 显示了急性和慢性损伤。急性天然 T1w MRI 体积（平均 102.1±48.5mm ）和深度（4.9±1.2mm）与慢性组织学体积（105.9±51.8mm ）和深度（4.8±1.3mm）高度相关，相关系数 R 分别为 0.881（P<0.001）和 0.874（P<0.001）。与慢性组织学损伤体积和深度相比，急性 LGE-MRI 的增强体积明显更高，为 499.7±214.4mm （P<0.001），深度为 7.5±1.8mm （P<0.001）。
RF 消融后立即获取的天然 T1w MRI 是慢性损伤大小的良好预测指标。急性 LGE-MRI 显著高估了慢性损伤大小。
