Schuster Andreas, Paul Matthias, Bettencourt Nuno, Hussain Shazia T, Morton Geraint, Kutty Shelby, Bigalke Boris, Chiribiri Amedeo, Perera Divaka, Nagel Eike, Beerbaum Philipp
Department of Cardiology and Pulmonology, Georg-August-University and German Center for Cardiovascular Research (DZHK, Partner Site), Göttingen, Germany; King's College London British Heart Foundation (BHF) Centre of Excellence; National Institute of Health Research (NIHR) Biomedical Research Centre at Guy's and St. Thomas' NHS Foundation Trust; Wellcome Trust and Engineering and Physical Sciences Research Council (EPSRC) Medical Engineering Centre; Division of Imaging Sciences and Biomedical Engineering; The Rayne Institute, St. Thomas´ Hospital, London, United Kingdom.
King's College London British Heart Foundation (BHF) Centre of Excellence; National Institute of Health Research (NIHR) Biomedical Research Centre at Guy's and St. Thomas' NHS Foundation Trust; Wellcome Trust and Engineering and Physical Sciences Research Council (EPSRC) Medical Engineering Centre; Division of Imaging Sciences and Biomedical Engineering; The Rayne Institute, St. Thomas´ Hospital, London, United Kingdom.
PLoS One. 2015 Apr 7;10(4):e0122858. doi: 10.1371/journal.pone.0122858. eCollection 2015.
To determine whether quantitative wall motion assessment by CMR myocardial feature tracking (CMR-FT) would reduce the impact of observer experience as compared to visual analysis in patients with ischemic cardiomyopathy (ICM).
15 consecutive patients with ICM referred for assessment of hibernating myocardium were studied at 3 Tesla using SSFP cine images at rest and during low dose dobutamine stress (5 and 10 μg/kg/min of dobutamine). Conventional visual, qualitative analysis was performed independently and blinded by an experienced and an inexperienced reader, followed by post-processing of the same images by CMR-FT to quantify subendocardial and subepicardial circumferential (Eccendo and Eccepi) and radial (Err) strain. Receiver operator characteristics (ROC) were assessed for each strain parameter and operator to detect the presence of inotropic reserve as visually defined by the experienced observer.
141 segments with wall motion abnormalities at rest were eligible for the analysis. Visual scoring of wall motion at rest and during dobutamine was significantly different between the experienced and the inexperienced observer (p<0.001). All strain values (Eccendo, Eccepi and Err) derived during dobutamine stress (5 and 10 μg/kg/min) showed similar diagnostic accuracy for the detection of contractile reserve for both operators with no differences in ROC (p>0.05). Eccendo was the most accurate (AUC of 0.76, 10 μg/kg/min of dobutamine) parameter. Diagnostic accuracy was worse for resting strain with differences between operators for Eccendo and Eccepi (p<0.05) but not Err (p>0.05).
Whilst visual analysis remains highly dependent on operator experience, quantitative CMR-FT analysis of myocardial wall mechanics during DS-CMR provides diagnostic accuracy for the detection of inotropic reserve regardless of operator experience and hence may improve diagnostic robustness of low-dose DS-CMR in clinical practice.
确定与视觉分析相比，采用心脏磁共振心肌特征追踪（CMR-FT）进行定量壁运动评估是否会降低观察者经验对缺血性心肌病（ICM）患者的影响。
连续纳入15例因冬眠心肌评估而转诊的ICM患者，在3特斯拉场强下，使用稳态自由进动 cine 图像在静息状态和低剂量多巴酚丁胺负荷（5和10μg/kg/min多巴酚丁胺）期间进行研究。由一位经验丰富的和一位经验不足的阅片者独立且盲法进行传统的视觉定性分析，随后对相同图像进行CMR-FT后处理，以量化心内膜下和心外膜下周向（Eccendo和Eccepi）及径向（Err）应变。针对每个应变参数和阅片者评估受试者工作特征（ROC）曲线，以检测由经验丰富的观察者视觉定义的变力性储备的存在情况。
141个静息时存在壁运动异常的节段符合分析条件。经验丰富的和经验不足阅片者对静息及多巴酚丁胺负荷期间壁运动的视觉评分存在显著差异（p<0.001）。多巴酚丁胺负荷（5和10μg/kg/min）期间得出的所有应变值（Eccendo、Eccepi和Err）对两位阅片者检测收缩储备的诊断准确性相似，ROC曲线无差异（p>0.05）。Eccendo是最准确的参数（多巴酚丁胺10μg/kg/min时AUC为0.76）。静息应变的诊断准确性较差，Eccendo和Eccepi在阅片者之间存在差异（p<0.05），但Err无差异（p>0.05）。
虽然视觉分析高度依赖于阅片者经验，但在多巴酚丁胺负荷心脏磁共振（DS-CMR）期间对心肌壁力学进行定量CMR-FT分析，无论阅片者经验如何，对检测变力性储备均具有诊断准确性，因此可能会提高临床实践中低剂量DS-CMR的诊断稳健性。
