RESULTS: Included were 78 patients with severe aortic stenosis who underwent CT imaging prior to TAVR. The thickness of muscular IVS was measured in the coronal view, in systolic phases, at 1, 2, 5, and 10 mm below the membranous septum (MS). The primary endpoint was a composite of conduction disturbance following TAVR. Conduction disturbances occurred in 24 out of 78 patients (30.8%). Those with conduction disturbances were significantly more likely to have a thinner IVS than those without conduction disturbances at every measured IVS level (2.98 ± 0.52 mm vs. 3.38 ± 0.52 mm, 4.10 ± 1.02 mm vs. 4.65 ± 0.78 mm, 6.11 ± 1.12 mm vs. 6.88 ± 1.03 mm, and 9.72 ± 1.95 mm vs. 10.70 ± 1.55 mm for 1, 2, 5 and 10 mm below MS, respectively, P < 0.05 for all). Multivariable logistic regression analysis showed that pre-procedural IVS thickness (<4 mm at 2 mm below the MS) was a significant independent predictor of post-procedural conduction disturbance (adjOR 7.387, 95% CI: 2.003-27.244, P = 0.003).
CONCLUSIONS: Pre-procedural CT assessment of basal IVS thickness is a novel predictive marker for the risk of conduction disturbances following TAVR. The IVS thickness potentially acts as an anatomical barrier protecting the underlying conduction system from mechanical compression during TAVR.
背景:IVS是房室传导轴所在的心脏电传导系统的关键区域。
方法:包括78例严重主动脉瓣狭窄患者,在TAVR之前进行了CT成像。在冠状视图中测量肌肉IVS的厚度,在收缩期,在膜隔膜(MS)下方1、2、5和10mm处。主要终点是TAVR后传导紊乱的复合。
结果:78例患者中有24例发生传导障碍(30.8%)。在每个测量的IVS水平(2.98±0.52mmvs.3.38±0.52mm,4.10±1.02mmvs.4.65±0.78mm,6.11±1.12mmvs.6.88±1.03mm,和9.72±1.95毫米与对于MS以下1、2、5和10mm,分别为10.70±1.55mm,全部p<0.05)。多变量logistic回归分析显示,术前IVS厚度(MS以下2mm处<4mm)是术后传导障碍的重要独立预测因素(adjOR7.387,95%CI:2.003-27.244,p=0.003)。
结论:术前CT评估基础IVS厚度是TAVR后传导紊乱风险的一种新的预测指标。IVS厚度潜在地充当解剖屏障,保护底层传导系统在TAVR期间免受机械压缩。