University Hospital for Radiology, Medical University Innsbruck, Anichstraße 35, 6020 Innsbruck, Austria.
University Hospital for Internal Medicine III (Cardiology and Angiology), Medical University Innsbruck, Anichstraße 35, 6020 Innsbruck, Austria.
Eur J Radiol. 2021 Apr;137:109573. doi: 10.1016/j.ejrad.2021.109573. Epub 2021 Jan 31.
To prospectively compare image-quality, reliability and graft sizing of a prototype self-navigated and a navigator-gated non-contrast three dimensional (3D) whole-heart magnetic-resonance-angiography (MRA) sequence with computed-tomography-angiography (CTA) for planning transcatheter-aortic-valve-implantation (TAVI).
Self- and navigator-gated 1.5 T MRA were performed in 27 patients (aged 83 ± 5 years, 41 % male) for aortic root sizing and coronary ostia height measurements; 15 (56 %) patients underwent additional CTA. Subjective-image quality was graded on a 4-point Likert scale, objective MRA image-quality was assessed by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Continuous MRA and CTA measurements were analyzed with regression and Bland-Altman analysis, valve sizing by kappa statistics.
Median image-quality as rated by two observers was 1.5 [interquartile range (IQR) 1-3] for self-navigated MRA and 1 [IQR 1-2] for navigator-gated MRA (p = 0.059). SNR and CNR were comparable between MRA sequences (p = 0.471 and 0.445, respectively). Acquisition time was shorter for self-navigated MRA compared to navigator-gated MRA (5.5 ± 1 min vs, 6.5 ± 2 min, p = 0.029). Inter-observer correlation of aortic root measurements was high to very high for both self- and navigator-gated MRA (r = 0.75 to 0.94 and r = 0.85 to 0.96, respectively, all p < 0.0001). Theoretical prosthetic valve sizing of self-navigated MRA and CTA was equivalent (κ = 1). However, in four patients (15 %) one coronary ostium each (right coronary artery 3, left main artery 1) was not clearly definable on self-navigated MRA.
Self-navigated MRA enables aortic annulus TAVI measurements without significant difference to navigator-gated MRA at shortened acquisition time. Prosthesis sizing by self-navigated MRA measurements is equivalent to navigator-gated MRA and CTA-based choice.
前瞻性比较原型自主导航和导航门控非对比三维（3D）全心脏磁共振血管造影（MRA）序列与计算机断层血管造影（CTA）在经导管主动脉瓣植入（TAVI）术前评估中的图像质量、可靠性和移植物大小测量。
对 27 例患者（年龄 83±5 岁，41%为男性）进行自主导航和导航门控 1.5T MRA，用于主动脉根部大小测量和冠状动脉开口高度测量；15 例（56%）患者接受了额外的 CTA。使用 4 分制 Likert 量表对主观图像质量进行分级，通过信噪比（SNR）和对比噪声比（CNR）评估客观 MRA 图像质量。对连续 MRA 和 CTA 测量值进行回归和 Bland-Altman 分析，采用 Kappa 统计分析瓣膜大小。
两位观察者评估的中位数图像质量，自主导航 MRA 为 1.5[四分位距（IQR）1-3]，导航门控 MRA 为 1[IQR 1-2]（p=0.059）。MRA 序列之间 SNR 和 CNR 无差异（p=0.471 和 0.445）。与导航门控 MRA 相比，自主导航 MRA 的采集时间更短（5.5±1min 比 6.5±2min，p=0.029）。自主导航和导航门控 MRA 的主动脉根部测量值的观察者间相关性均为高度至非常高度（r=0.75 至 0.94 和 r=0.85 至 0.96，均 p<0.0001）。自主导航 MRA 和 CTA 的理论人工瓣膜大小测量值相当（κ=1）。然而，在 4 例患者（15%）中，各有一个冠状动脉开口（右冠状动脉 3 个，左主干动脉 1 个）在自主导航 MRA 上无法明确界定。
自主导航 MRA 可用于主动脉瓣环 TAVI 测量，与导航门控 MRA 相比，采集时间缩短，无明显差异。自主导航 MRA 测量的人工瓣膜大小与导航门控 MRA 和 CTA 选择相当。
