D'Errico Luigia, Lamacie Mariana M, Jimenez Juan Laura, Deva Djeven, Wald Rachel M, Ley Sebastian, Hanneman Kate, Thavendiranathan Paaladinesh, Wintersperger Bernd J
Department of Medical Imaging, Peter Munk Cardiac Centre, University Health Network, Toronto, Canada.
Department of Medical Imaging, University of Toronto, Toronto, Canada.
J Cardiovasc Magn Reson. 2016 Sep 22;18(1):60. doi: 10.1186/s12968-016-0282-x.
Test-retest reproducibility is of utmost importance in follow-up of right ventricular (RV) volumes and function; optimal slice orientation though is not yet known. We compared test-retest reproducibility and intra-/inter-observer variability of right ventricular (RV) volumes and function assessed with short-axis and transverse cardiovascular magnetic resonance (CMR).
Eighteen volunteers underwent cine CMR for RV assessment obtaining ventricular coverage in short-axis and transverse slice orientation. Additional 2D phase contrast flow imaging of the main pulmonary artery (MPA) was performed. After complete repositioning repeat acquisitions were performed. Data sets were contoured by two blinded observers. Statistical analysis included Student's t-test, Bland-Altman plots, intra-class correlation coefficient (ICC) and 2-way ANOVA, SEM and minimal detectable difference calculations.
Heart rates (65.0 ± 7.4 vs. 67.6 ± 9.9 bpm; P = 0.1) and MPA flow (89.8 ± 16.6 vs. 87.2 ± 14.9 mL; P = 0.1) did not differ between imaging sessions. EDV and ESV demonstrated an inter-study bias of 0.4 %[-9.5 %,10.3 %] and 2.1 %[-12.3 %,16.4 %] for short-axis and 1.1 %[-7.3 %,9.4 %] and 0.8 %[-16.0 %,17.6 %] for transverse orientation, respectively. There was no significant interaction between imaging orientation and interstudy reproducibility (p = 0.395-0.824), intra-observer variability (p = 0.726-0.862) or inter-observer variability (p = 0.447-0.706) by 2-way ANOVA. Inter-observer agreement by ICC was greater for short axis versus transverse orientation for all parameters (0.769-0.986 vs. 0.625-0.983, respectively). Minimal detectable differences for short axis and transverse orientations were 10.1 mL/11.5 mL for EDV, 8.3 mL/8.4 mL for ESV and 4.1 % vs. 4.7 % for EF, respectively.
Short-axis and transverse orientation both provide reliable and reproducible measures for follow-up of RV volumes and global function. Therefore, additional transverse SSFP cine CMR may not necessarily be required if performed for the sole purpose of quantitative volumetric RV assessment.
在右心室（RV）容积和功能的随访中，重测可重复性至关重要；然而，最佳的层面取向尚不清楚。我们比较了短轴和横轴心血管磁共振（CMR）评估右心室（RV）容积和功能的重测可重复性以及观察者内/间变异性。
18名志愿者接受了用于RV评估的电影CMR检查，获得了短轴和横轴层面取向的心室覆盖范围。还对主肺动脉（MPA）进行了额外的二维相位对比血流成像。在完全重新定位后进行重复采集。数据集由两名不知情的观察者进行轮廓描绘。统计分析包括学生t检验、Bland-Altman图、组内相关系数（ICC）和双向方差分析、标准误和最小可检测差异计算。
两次成像检查之间的心率（65.0±7.4对67.6±9.9次/分钟；P=0.1）和MPA血流量（89.8±16.6对87.2±14.9毫升；P=0.1）没有差异。短轴方向的舒张末期容积（EDV）和收缩末期容积（ESV）的研究间偏差分别为0.4%[-9.5%，10.3%]和2.1%[-12.3%，16.4%]，横轴方向分别为1.1%[-7.3%，9.4%]和0.8%[-16.0%，17.6%]。通过双向方差分析，成像取向与研究间可重复性（p=0.395 - 0.824）、观察者内变异性（p=0.726 - 0.862）或观察者间变异性（p=0.447 - 0.706）之间没有显著交互作用。对于所有参数，短轴方向的观察者间ICC一致性高于横轴方向（分别为0.769 - 0.986对0.625 - 0.983）。短轴和横轴方向的最小可检测差异分别为：EDV为每搏量10.1毫升/11.5毫升，ESV为每搏量8.3毫升/8.4毫升，射血分数（EF）为4.1%对4.7%。
短轴和横轴方向均为RV容积和整体功能的随访提供了可靠且可重复测量的方法。因此，如果仅为定量RV容积评估而进行CMR检查，不一定需要额外的横轴稳态自由感应衰减（SSFP）电影成像。
