Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center (MUMC+), Maastricht, the Netherlands.
Department of Physiology, CARIM, Maastricht University, Maastricht, the Netherlands.
JACC Clin Electrophysiol. 2024 Oct;10(10):2186-2197. doi: 10.1016/j.jacep.2024.05.017. Epub 2024 Jul 10.
Dark-blood late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) has better correlation with bipolar voltage (BiV) to define ablation scar in the left atrium (LA) compared to conventional bright-blood LGE CMR.
This study sought to determine the optimal signal intensity threshold of dark-blood LGE CMR to identify LA ablation scar.
In 54 patients scheduled for atrial fibrillation ablation, image intensity ratios (IIRs) were derived from preprocedural dark-blood LGE CMR. In 26 patients without previous ablation, the upper limit of normal was derived from the 95th and 98th percentiles of pooled IIR values. In 28 patients with previous atrial fibrillation ablation, BiV was compared with the corresponding IIR. Receiver-operating characteristics analyses were employed to determine the optimal IIR threshold (ie, the point with the smallest distance to the upper left corner of the receiver-operating characteristics) for LA ablation scar (BiV ≤0.15 mV).
Upper limit of normal corresponded to IIR values 1.16 and 1.21, yielding low sensitivities of 0.32 and 0.09 to detect LA ablation scar. Receiver-operating characteristics analysis of IIR and BiV comparison achieved a median area under the curve of 0.77. Median optimal IIR threshold for LA ablation scar was 1.09, with an average sensitivity of 0.73, specificity of 0.75, and accuracy of 0.71. Median IIR thresholds of 1.00 and 1.10 corresponded to 80% sensitivity and 80% specificity, respectively. There was considerable interpatient variability: optimal IIR thresholds per patient ranged from 1.01 to 1.22.
The optimal IIR threshold to identify LA ablation scar by dark-blood LGE CMR is 1.09. Because of interpatient variability, the investigators recommend using a lower (1.00) and upper (1.10) threshold to prevent over- or underestimation of ablation scar.
与传统亮血 LGE CMR 相比，黑血 LGE CMR 与双极电压（BiV）的相关性更好，可用于定义左心房（LA）消融瘢痕。
本研究旨在确定黑血 LGE CMR 中最佳信号强度阈值，以识别 LA 消融瘢痕。
在 54 例行房颤消融的患者中，从术前黑血 LGE CMR 中得出图像强度比（IIR）。在 26 例无既往消融的患者中，通过 95%和 98%的 IIR 值的百分位数得出正常值上限。在 28 例既往有房颤消融的患者中，将 BiV 与相应的 IIR 进行比较。采用受试者工作特征分析确定 LA 消融瘢痕（BiV≤0.15 mV）的最佳 IIR 阈值（即距受试者工作特征左上角最近的点）。
正常值上限对应于 IIR 值 1.16 和 1.21，检测 LA 消融瘢痕的灵敏度分别为 0.32 和 0.09，较低。IIR 和 BiV 比较的受试者工作特征分析获得的曲线下面积中位数为 0.77。LA 消融瘢痕的最佳 IIR 阈值中位数为 1.09，平均灵敏度为 0.73，特异性为 0.75，准确性为 0.71。IIR 阈值为 1.00 和 1.10 时，分别对应 80%的灵敏度和 80%的特异性。患者间存在相当大的变异性：每个患者的最佳 IIR 阈值范围为 1.01 至 1.22。
通过黑血 LGE CMR 识别 LA 消融瘢痕的最佳 IIR 阈值为 1.09。由于患者间的变异性，研究人员建议使用较低（1.00）和较高（1.10）的阈值，以防止消融瘢痕的过度或低估。
