Department of Radiology and Radiological Science, Division of Cardiovascular Imaging.
Unit of Radiology, IRCCS Policlinico San Donato, San Donato Milanese.
J Thorac Imaging. 2018 Jan;33(1):60-67. doi: 10.1097/RTI.0000000000000278.
The aim of this study was to prospectively evaluate the technical feasibility of a noncontrast magnetic resonance angiography (MRA) protocol using investigational prototype self-navigated 3D (SN3D) radial whole-heart and quiescent-interval single-shot (QISS) pulse sequences regarding their potential in planning transcatheter aortic valve replacement (TAVR).
Five patients (76±7 y) with severe aortic valve stenosis and prior computed tomographic angiography (CTA) for TAVR planning and 10 healthy volunteers (28±6 y) underwent noncontrast MRA on a 1.5 T system. A SN3D whole-heart acquisition was used to assess the aortic root anatomy. Evaluation of the aortoiliac access route was performed with both SN3D and QISS. Measurements were compared among SN3D, QISS, and CTA using a paired t test or 1-way analysis of variance. Image quality ratings and contrast-to-noise ratios (CNR) were analyzed using Mann-Whitney U tests. Interobserver agreement was evaluated using Cohen's κ.
The combined SN3D and QISS protocol provided a 10.1±1.6-minute acquisition time. TAVR-relevant evaluation was technically feasible in healthy volunteers. All measurements showed good agreement with CTA in patients (all P>0.098). SN3D and QISS produced similar image quality both in volunteers and in patients (all P>0.122). There was no difference in qualitative ratings between MRA and CTA (all P>0.119). Interobserver agreement was good for MRA (κ=0.71 to 0.76) and excellent for CTA (κ=0.82 to 0.84). Thoracic SN3D provided a similar CNR compared with CTA (P=0.117). CTA yielded higher CNR in the abdominopelvic region compared with QISS (P=0.006).
A noncontrast MRA protocol combining SN3D and QISS acquisitions for the assessment of cardiac and vascular access route anatomy has technical feasibility for TAVR planning.
本研究旨在前瞻性评估使用探索性原型自主导航 3D（SN3D）径向全心和静息间隔单次激发（QISS）脉冲序列的非对比磁共振血管造影（MRA）方案在经导管主动脉瓣置换术（TAVR）计划中的技术可行性。
5 例（76±7 岁）严重主动脉瓣狭窄患者，均有 TAVR 计划的计算机断层血管造影（CTA）检查，以及 10 例健康志愿者（28±6 岁），均在 1.5T 系统上进行非对比 MRA。采用 SN3D 全心采集评估主动脉根部解剖结构。使用 SN3D 和 QISS 评估主髂动脉入路。使用配对 t 检验或单因素方差分析比较 SN3D、QISS 和 CTA 之间的测量值。使用 Mann-Whitney U 检验分析图像质量评分和对比噪声比（CNR）。采用 Cohen's κ评估观察者间一致性。
联合 SN3D 和 QISS 方案的采集时间为 10.1±1.6 分钟。健康志愿者的 TAVR 相关评估具有技术可行性。所有患者的测量值与 CTA 均具有良好的一致性（均 P>0.098）。SN3D 和 QISS 在志愿者和患者中均产生相似的图像质量（均 P>0.122）。MRA 和 CTA 的定性评分无差异（均 P>0.119）。观察者间对 MRA 的一致性良好（κ=0.71 至 0.76），对 CTA 的一致性极好（κ=0.82 至 0.84）。与 CTA 相比，SN3D 提供了类似的胸部 CNR（P=0.117）。与 QISS 相比，CTA 在腹盆区提供了更高的 CNR（P=0.006）。
用于评估心脏和血管入路解剖结构的结合 SN3D 和 QISS 采集的非对比 MRA 方案具有 TAVR 计划的技术可行性。
