Shee Vikram, He Liwei, Liu Shenrong, Huang Xingfu, Chen Yanyu, Xie Liangzhen, Deng Xiaojiang, Peng Jian
Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, CHN.
Cureus. 2020 Jun 23;12(6):e8783. doi: 10.7759/cureus.8783.
Background Atrial fibrillation causes ischemic stroke when thrombi dislodge from a cardiac outpouching, the left atrial appendage (LAA), and embolize to the brain. LAA occlusion with the Watchman™ device (Boston Scientific Corporation, MA, USA), which prevents stroke, requires accurate LAA measurements for device sizing. We explore whether standard fluoroscopic LAA measurements improve when obtained at CT-derived viewing angles personalized to LAA anatomy while concurrently referring to three-dimensional (3D) CT. Methods Left atrial 3D reconstructions created from contrast CT (n=28) were analysed to identify personalized viewing angles wherein LAA dimensions (LAA maximum landing zone diameter and LAA length) were best observed. The 3D-CT reconstructions were then 3D printed with stands. Fluoroscopy of anatomically oriented models in the catheter lab simulated LAA angiography. Fluoroscopic images were acquired at standard (caudal 20˚/right anterior oblique 30˚) and personalized viewing angles. Repeated measurements of LAA dimensions were taken from CT (Control), fluoroscopy at standard angles (Standard), personalized angles (Blinded), and personalized angles while concurrently referring to 3D CT (Referred). Results Control measurements correlated and agreed better with Referred and Blinded measurements than with Standard measurements (diameter correlation and agreement: Control/Standard r=.554, limits of agreement [LOAs]=6.83/-5.91; Control/Blinded r=.641, LOA =5.67/-5.54; Control/Referred r=.741, LOA=4.69/-4.14; length correlation and agreement: Control/Standard r=.829, LOA=9.61/-3.02; Control/Blinded r=0.789, LOA=7.13/-4.94; Control/Referred r=.907, LOA=4.84/-4.13). Personalized angles resulted in hypothetical device size predictions more consistent with Control (device size correlation: Control/Standard r=.698, Control/Blinded r=.731, Control/Referred r=.893, P<0.001). False ineligibility rates were Standard=6/28, Blinded=6/28, and Referred=2/28. Conclusion This simulation suggests that personalized fluoroscopic viewing angles with in-procedural reference to 3D CT may improve the accuracy of LAA maximum landing zone diameter and length measurements at the Watchman landing zone. This improvement may result in more consistent device size selection and procedural eligibility assessment. Further clinical research on these interventions is merited.
当血栓从心脏外凸部即左心耳（LAA）脱落并栓塞至脑部时，心房颤动会引发缺血性卒中。使用Watchman™ 装置（美国马萨诸塞州波士顿科学公司）封堵LAA可预防卒中，这需要准确测量LAA以确定装置尺寸。我们探讨在根据LAA解剖结构个性化的CT衍生视角下并同时参考三维（3D）CT进行标准荧光透视LAA测量时，测量结果是否会得到改善。方法：分析由对比增强CT（n = 28）创建的左心房3D重建图像，以确定能最佳观察LAA尺寸（LAA最大着陆区直径和LAA长度）的个性化视角。然后将3D - CT重建图像与支架一起进行3D打印。在导管实验室对具有解剖学方向的模型进行荧光透视，模拟LAA血管造影。在标准视角（尾侧20˚/右前斜30˚）和个性化视角下采集荧光透视图像。从CT（对照）、标准视角荧光透视（标准）、个性化视角（盲法）以及同时参考3D CT的个性化视角（参考）中重复测量LAA尺寸。结果：对照测量与参考和盲法测量的相关性及一致性优于与标准测量的相关性及一致性（直径相关性及一致性：对照/标准r = 0.554，一致性界限[LOA] = 6.83 / - 5.91；对照/盲法r = 0.641，LOA = 5.67 / - 5.54；对照/参考r = 0.741，LOA = 4.69 / - 4.14；长度相关性及一致性：对照/标准r = 0.829，LOA = 9.61 / - 3.02；对照/盲法r = 0.789，LOA = 7.13 / - 4.94；对照/参考r = 0.907，LOA = 4.84 / - 4.13）。个性化视角得出的假设装置尺寸预测与对照更一致（装置尺寸相关性：对照/标准r = 0.698，对照/盲法r = 0.731，对照/参考r = 0.893，P < 0.001）。假不合格率分别为标准组 = 6/28，盲法组 = 6/28，参考组 = 2/28。结论：该模拟表明，在手术过程中参考3D CT的个性化荧光透视视角可能会提高Watchman着陆区LAA最大着陆区直径和长度测量的准确性。这种改进可能会使装置尺寸选择和手术合格性评估更加一致。值得对这些干预措施进行进一步的临床研究。
