Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
JACC Cardiovasc Imaging. 2013 Jan;6(1):42-52. doi: 10.1016/j.jcmg.2012.05.016.
This study aimed to evaluate the feasibility and accuracy of real-time integration of multidetector computed tomography (MDCT) derived coronary anatomy and epicardial fat distribution and its impact on electroanatomical mapping and ablation.
Epicardial catheter ablation for ventricular arrhythmias (VA) is an important therapeutic option in patients after endocardial ablation failure. However, epicardial mapping and ablation are limited by the presence of coronary arteries and epicardial fat.
Twenty-eight patients (21 male, age 59 ± 16 years) underwent combined endo-epicardial electroanatomical mapping. Prior to the procedure, MDCT derived coronary anatomy and epicardial fat meshes were loaded into the mapping system (CARTO XP, Biosense Webster Inc, Diamond Bar, California). Real-time registration of MDCT data was performed after endocardial mapping. The distance between epicardial ablation sites and coronary arteries was assessed by registered MDCT and angiography. After the procedure, mapping and ablation points were superimposed on the MDCT using a reversed registration matrix for head-to-head comparison of mapping data and corresponding fat thickness.
Image registration was successful and accurate in all patients (position error 2.8 ± 1.3 mm). At sites without evidence for scar, epicardial bipolar voltage decreased significantly (p < 0.001) with increasing fat thickness. Forty-six VA were targeted; 25 (54%) were abolished by catheter ablation, in 21 (46%) ablation failed. In 5 VA no target site was identified and in 3 VA adhesions prevented mapping. In 2 VA ablation was withheld due to His-bundle vicinity and in 7 VA due to proximity of coronary arteries. In 4 VA catheter ablation was ineffective. At ineffective ablation sites epicardial fat was significantly thicker compared to successful sites (16.9 ± 6.8 mm [range 7.3 to 22.2 mm] and 1.5 ± 2.1 mm [range 0.0 to 6.1 mm], p = 0.002).
Real-time image integration of pre-acquired MDCT information is feasible and accurate. Epicardial fat >7 mm and the presence of coronary arteries are important reasons for epicardial ablation failure. Visualization of fat thickness during the procedure may facilitate interpretation of bipolar electrograms and identification of ineffective ablation sites.
本研究旨在评估将多排螺旋 CT（MDCT）得出的冠状动脉解剖结构和心外膜脂肪分布实时整合，并将其应用于心内膜标测和消融的可行性和准确性。
心外膜导管消融术是心内膜消融失败后治疗室性心律失常（VA）的重要治疗选择。然而，心外膜标测和消融受到冠状动脉和心外膜脂肪的限制。
28 名患者（21 名男性，年龄 59 ± 16 岁）接受了心内外膜联合电解剖标测。在进行该手术之前，将 MDCT 得出的冠状动脉解剖结构和心外膜脂肪网格加载到映射系统中（CARTO XP，Biosense Webster Inc，加利福尼亚州钻石吧）。在心内膜标测后，进行 MDCT 数据的实时注册。使用已注册的 MDCT 和血管造影评估心外膜消融部位与冠状动脉之间的距离。手术后，使用反转注册矩阵将标测和消融点叠加到 MDCT 上，对头到头比较标测数据和相应的脂肪厚度。
在所有患者中，图像注册均成功且准确（位置误差 2.8 ± 1.3mm）。在没有疤痕证据的部位，随着脂肪厚度的增加，心外膜双极电压显著降低（p < 0.001）。共靶向 46 个 VA；25 个（54%）通过导管消融消除，21 个（46%）消融失败。5 个 VA 未确定靶点，3 个 VA 粘连妨碍了标测。2 个 VA 由于希氏束附近和 7 个 VA 由于冠状动脉附近而放弃消融。4 个 VA 导管消融无效。在无效消融部位，心外膜脂肪明显较厚，与成功部位相比（16.9 ± 6.8mm[范围 7.3 至 22.2mm]和 1.5 ± 2.1mm[范围 0.0 至 6.1mm]，p = 0.002）。
预先获取的 MDCT 信息的实时图像集成是可行和准确的。心外膜脂肪>7mm 和冠状动脉的存在是心外膜消融失败的重要原因。在手术过程中观察脂肪厚度有助于解释双极电图并识别无效的消融部位。
