Background In patients with atrial fibrillation (AF), imaging examinations have an important role in planning ablation by imaging the pulmonary veins (PV). The PV anatomy is conventionally assessed before ablation using computer tomography (CT) or 3 dimensional (3D) contrast-enhanced cardiac magnetic resonance (CMR) imaging. The new 3-dimensional, free-breathing BOOST (Bright-blood and black-blOOd phase SensiTive inversion recovery) cardiac magnetic resonance (CMR) sequence is suitable for imaging the left atrium without the addition of contrast agent. Purpose The aim of our study was to investigate the BOOST sequence for the imaging of PVs, and the effect of heart rate and rhythm on image quality. Methods Forty-seven patients underwent and BOOST CMR before ablation, 25 of them had also left atrial CT angiography (CTA). The BOOST sequence was performed using T2 preparation pre-pulse (T2prep) and magnetization transfer preparation (MTC) techniques. The image quality was analyzed using a subjective Likert scale and quantitatively by determining the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Heart rate and rhythm were assessed by 12-lead ECG. Results MTC-BOOST images were suitable for PVs analysis in all cases, whereas the assessment of PVs on T2prep-BOOST images was inadequate in the majority of cases due to artifacts. CTA showed the same PV anatomy as assessed with BOOST CMR. Based on the operating electrophysiologists’ subjective opinion, the quality of the CTA scans was better compared with BOOST sequence. Still, they found the CMR images appropriate for procedural planning in 43 out of 47 cases (91%). SNR and CNR values of the MTC-BOOST bright-blood images were higher if patients had sinus rhythm. We found a significant or nearly significant negative correlation between heart rate and the SNR and CNR values of MTC-BOOST bright-blood images. Conclusions MTC-BOOST images are suitable for visualisation of PVs, producing diagnostic image quality in 100% of cases. In the majority of cases, MTC-BOOST images were appropriate for procedural planning before ablation. Image quality is affected by the patients' heart rate and frequency. Figure 1: MTC BOOST bright blood image of the left atrium and the right pulmonary veins (arrows)

中文翻译：

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非对比 BOOST 心脏磁共振序列的图像质量，用于可视化心房颤动患者的肺静脉


背景 在心房颤动 （AF） 患者中，影像学检查通过肺静脉 （PV） 成像来规划消融手术中起着重要作用。消融前通常使用计算机断层扫描 （CT） 或 3 维 （3D） 对比增强心脏磁共振 （CMR） 成像评估 PV 解剖结构。新的 3 维自由呼吸 BOOST（亮血和黑 blOOd 期传感倒位恢复）心脏磁共振 （CMR） 序列适用于无需添加造影剂即可对左心房进行成像。目的 我们研究的目的是研究 PV 成像的 BOOST 序列，以及心率和节律对图像质量的影响。方法 47 例患者在消融前接受了 BOOST CMR，其中 25 例还离开了心房 CT 血管造影 （CTA）。使用 T2 制备前脉冲 （T2prep） 和磁化转移制备 （MTC） 技术进行 BOOST 序列。使用主观李克特量表分析图像质量，并通过确定信噪比 （SNR） 和对比噪声比 （CNR） 进行定量分析。通过 12 导联心电图评估心率和心律。结果 MTC-BOOST 图像在所有情况下都适用于PVs分析，而由于伪影，T2prep-BOOST图像上的PVs评估在大多数情况下是不充分的。CTA 显示与 BOOST CMR 评估的 PV 解剖结构相同。根据手术电生理学家的主观意见，与 BOOST 序列相比，CTA 扫描的质量更好。尽管如此，他们发现 47 例病例中有 43 例 （91%） 的 CMR 图像适合程序规划。如果患者有窦性心律，则 MTC-BOOST 亮血图像的 SNR 和 CNR 值更高。 我们发现心率与 MTC-BOOST 亮血图像的 SNR 和 CNR 值之间存在显著或接近显着的负相关。结论 MTC-BOOST 图像适用于 PV 的可视化，在 100% 的病例中产生诊断图像质量。在大多数情况下，MTC-BOOST 图像适用于消融前的手术计划。图像质量受患者心率和频率的影响。图 1：MTC BOOST 左心房和右肺静脉的亮血图像（箭头）