Faddis Mitchell N, Blume Walter, Finney Jennifer, Hall Andrew, Rauch John, Sell Jon, Bae Kyongtae Ty, Talcott Michael, Lindsay Bruce
Washington University School of Medicine, St Louis, Mo, USA.
Circulation. 2002 Dec 3;106(23):2980-5. doi: 10.1161/01.cir.0000038704.84304.6f.
Ablation of complex arrhythmias would be greatly facilitated by more precise control of ablation catheters. A feasibility study was performed in animals to evaluate a novel magnetic guidance system (MGS) that generates a magnetic field to control the movement and position of a magnetic ablation catheter.
The MGS is composed of a digital biplanar fluoroscope within an array of superconducting electromagnets that surround the torso of the experimental animal and a computer control system that generates a composite magnetic field for directional catheter deflection. Magnetic catheter navigation was performed in dogs and pigs (20 to 30 kg). A 7F magnetic ablation catheter was used for intracardiac navigation and radiofrequency ablation. The performance of a standard 7F deflectable catheter was not affected by the MGS. The magnetic catheter was navigated successfully to 51 predefined targets throughout the heart in 6 animals. In 5 animals, the magnetic catheter, guided by a 3D computed tomogram, was successfully navigated to all pulmonary veins. Navigation accuracy was estimated as <1 mm displacement from the target. The magnetic catheter was used to ablate the atrioventricular node in 4 animals and to perform linear ablations across the endocardial surface underlying an epicardial multielectrode recording plaque in 4 animals.
These results demonstrate that the MGS can navigate and stabilize an ablation catheter at endocardial targets. Linear or focal radiofrequency ablation with the magnetic catheter is not compromised by the magnetic field. This technology provides precise control of endocardial catheters.
更精确地控制消融导管将极大地促进复杂心律失常的消融治疗。我们在动物身上进行了一项可行性研究，以评估一种新型磁导航系统（MGS），该系统可产生磁场来控制磁性消融导管的移动和位置。
MGS由置于环绕实验动物躯干的超导电磁体阵列内的数字双平面荧光镜以及产生复合磁场以使导管定向偏转的计算机控制系统组成。在犬和猪（20至30千克）身上进行了磁性导管导航。使用一根7F磁性消融导管进行心内导航和射频消融。标准7F可弯曲导管的性能不受MGS影响。在6只动物中，磁性导管成功导航至心脏内51个预先定义的靶点。在5只动物中，在三维计算机断层扫描引导下，磁性导管成功导航至所有肺静脉。估计导航精度为距靶点的位移<1毫米。在4只动物中，使用磁性导管消融房室结，并在4只动物中在心外膜多电极记录板下方的心内膜表面进行线性消融。
这些结果表明，MGS能够将消融导管导航至心内膜靶点并使其稳定。磁性导管进行的线性或局部射频消融不受磁场影响。该技术可精确控制心内膜导管。
