Gallagher Peter, Martin Laura, Angel Lori, Tomassoni Gery
Central Baptist Hospital, Lexington, Kentucky, USA.
J Cardiovasc Electrophysiol. 2007 Feb;18(2):174-80. doi: 10.1111/j.1540-8167.2006.00711.x. Epub 2007 Jan 9.
The placement of left ventricular (LV) leads during cardiac resynchronization therapy (CRT) involves many technical difficulties. These difficulties increase procedural times and decrease procedural success rates.
A total of 50 patients with severe cardiomyopathy (mean LV ejection fraction was 21 +/- 6%) and a wide QRS underwent CRT implantation. Magnetic navigation (Stereotaxis, Inc.) was used to position a magnet-tipped 0.014'' guidewire (Cronus guidewire) within the coronary sinus (CS) vasculature. LV leads were placed in a lateral CS branch, either using a standard CS delivery sheath or using a "bare-wire" approach without a CS delivery sheath. The mean total procedure time was 98.1 +/- 29.1 minutes with a mean fluoroscopy time of 22.7 +/- 15.1 minutes. The mean LV lead positioning time was 10.4 +/- 7.6 minutes. The use of a delivery sheath was associated with longer procedure times 98 +/- 32 minutes vs 80 +/- 18 minutes (P = 0.029), fluoroscopy times 23 +/- 15 minutes vs 13 +/- 4 minutes (P = 0.0007) and LV lead positioning times 10 +/- 6 minutes vs 4 +/- 2 minutes (P = 0.015) when compared to a "bare-wire" approach. When compared with 52 nonmagnetic-assisted control CRT cases, magnetic navigation reduced total LV lead positioning times (10.4 +/- 7.6 minutes vs 18.6 +/- 18.9 minutes; P = 0.005). If more than one CS branch vessel was tested, magnetic navigation was associated with significantly shorter times for LV lead placement (16.2 +/- 7.7 minutes vs 36.4 +/- 23.4 minutes; P = 0.004).
Magnetic navigation is a safe, feasible, and efficient tool for lateral LV lead placement during CRT. Magnetic navigation during CRT allows for control of the tip direction of the Cronus 0.014'' guidewire using either a standard CS delivery sheath or "bare-wire" approach. Although there are some important limitations to the 0.014'' Cronus magnetic navigation can decrease LV lead placement times compared with nonmagnetic-assisted control CRT cases, particularly if multiple CS branches are to be tested.
心脏再同步治疗（CRT）期间左心室（LV）导线的放置存在许多技术难题。这些难题会延长手术时间并降低手术成功率。
共有50例重度心肌病患者（左心室平均射血分数为21±6%）且QRS波增宽，接受了CRT植入术。使用磁导航（Stereotaxis公司）将带磁头的0.014英寸导丝（Cronus导丝）置于冠状窦（CS）血管系统内。LV导线被放置在CS的外侧分支中，要么使用标准的CS输送鞘，要么采用无CS输送鞘的“裸导丝”方法。平均总手术时间为98.1±29.1分钟，平均透视时间为22.7±15.1分钟。LV导线平均放置时间为10.4±7.6分钟。与“裸导丝”方法相比，使用输送鞘会使手术时间更长（98±32分钟对80±18分钟；P = 0.029）、透视时间更长（23±15分钟对13±4分钟；P = 0.0007）以及LV导线放置时间更长（10±6分钟对4±2分钟；P = 0.015）。与52例非磁辅助对照CRT病例相比，磁导航缩短了LV导线的总放置时间（10.4±7.6分钟对18.6±18.9分钟；P = 0.005）。如果测试了不止一个CS分支血管，磁导航与显著更短的LV导线放置时间相关（16.2±7.7分钟对36.4±23.4分钟；P = 0.004）。
磁导航是CRT期间LV导线外侧放置的一种安全、可行且高效的工具。CRT期间的磁导航允许使用标准的CS输送鞘或“裸导丝”方法来控制Cronus 0.014英寸导丝的尖端方向。尽管0.014英寸Cronus磁导航存在一些重要局限性，但与非磁辅助对照CRT病例相比，它可以减少LV导线放置时间，特别是在要测试多个CS分支时。
