Abstract

Better understanding of the lead curvature, movement and their spatial distribution may be beneficial in developing lead testing methods, guiding implantations and improving life expectancy of implanted leads.

Objective

The aim of this two-phase study was to develop and test a novel biplane cine-fluoroscopy-based method to evaluate input parameters for bending stress in leads based on their in vivo 3D motion using precisely determined spatial distributions of lead curvatures. Potential tensile, compressive or torque forces were not subjects of this study.

Methods

A method to measure lead curvature and curvature evolution was initially tested in a phantom study. In the second phase using this model 51 patients with implanted ICD leads were included. A biplane cine-fluoroscopy recording of the intracardiac region of the lead was performed. The lead centerline and its motion were reconstructed in 3D and used to define lead curvature and curvature changes. The maximum absolute curvature C_max during a cardiac cycle, the maximum curvature amplitude C_amp and the maximum curvature C_max@amp at the location of C_amp were calculated. These parameters can be used to characterize fatigue stress in a lead under cyclical bending.

Results

The medians of C_amp and C_max@amp were 0.18 cm⁻¹ and 0.42 cm⁻¹, respectively. The median location of C_max was in the atrium whereas the median location of C_amp occurred close to where the transit through the tricuspid valve can be assumed. Increased curvatures were found for higher slack grades.

Conclusion

Our results suggest that reconstruction of 3D ICD lead motion is feasible using biplane cine-fluoroscopy. Lead curvatures can be computed with high accuracy and the results can be implemented to improve lead design and testing.

中文翻译：

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植入式心律转复除颤器导线体内运动的三维分析

摘要

更好地了解导线曲率、运动及其空间分布可能有利于开发导线测试方法、指导植入和提高植入导线的预期寿命。

客观的

这项两阶段研究的目的是开发和测试一种基于双平面电影透视的新型方法，以使用精确确定的导线曲率空间分布，根据导线的体内3D 运动评估导线弯曲应力的输入参数。潜在的拉伸力、压缩力或扭力不是本研究的主题。

方法

最初在体模研究中测试了一种测量导线曲率和曲率演变的方法。在使用该模型的第二阶段，包括 51 名植入 ICD 导线的患者。对导线的心内区域进行了双平面电影透视记录。导线中心线及其运动在 3D 中重建，并用于定义导线曲率和曲率变化。计算心动周期期间的最大绝对曲率C _{max 、最大曲率振幅}C _amp和C _amp位置处的最大曲率C _max@amp。这些参数可用于表征循环弯曲下引线中的疲劳应力。

结果

C _amp和C _max@amp的中值分别为0.18 cm ^-1和0.42 cm ^-1。C _max的中位位置在心房中，而C _amp的中位位置靠近可以假设通过三尖瓣的位置。发现更高的松弛等级增加了曲率。

结论

我们的结果表明，使用双平面电影透视重建 3D ICD 导联运动是可行的。可以高精度地计算引线曲率，并且可以实施结果以改进引线设计和测试。