Nichols Kenneth J, Van Tosh Andrew, Wang Yi, Palestro Christopher J, Reichek Nathaniel
Division of Nuclear Medicine and Molecular Imaging, North Shore-Long Island Jewish Health System, Manhasset and New Hyde Park, New York 11040, USA.
J Nucl Med. 2009 Jan;50(1):53-60. doi: 10.2967/jnumed.108.056085. Epub 2008 Dec 17.
Blood-pool (BP)-gated SPECT should be able to detect regional left ventricular (LV) dysfunction, as the modality is fully 3-dimensional and capable of resolving all cardiac chambers. This study investigates the hypothesis that LV segments that have abnormal regional wall motion (WM) on a cardiac MRI scan also have abnormal BP regional ejection fraction (EF) as computed by fully automated quantitation (AQ) of BP data.
A total of 34 patients evaluated for coronary artery disease who underwent visual assessment of WM by review of BP cines and cardiac MRI evaluations were included in this retrospective investigation. Cardiac MRI values for these patients were compared with an institutional database of cardiac MRI values for an age-matched cohort of 10 healthy volunteers. An AQ algorithm segmented the LV BPs on the BP tomograms and subdivided volumes into 17 subregions. Count-versus-time curves were fit to third-order Fourier series for each LV subvolume to compute regional EFs. For cardiac MRI data, endocardial and epicardial drawings were performed manually for 60 degrees samples of 11-13 short-axis tomograms spanning the entire heart, from which regional WM values were computed and rebinned into 17 conventional LV segments.
Global EF ranged from 12% to 75% on AQ and from 14% to 75% on cardiac MRI (Pearson correlation coefficient=0.95, P<0.0001). Differences were not significant between BP AQ and cardiac MRI in identifying the 12 patients with a global EF less than 35% (McNemar difference, 3%; P=1.0) and the 19 patients with an EF less than 50% (difference, 3%; P=1.0). BP AQ was more accurate than was visual assessment for identifying LV segments with abnormal cardiac MRI WM (receiver-operating-characteristic areas, 88% vs. 80%, P<0.0001) and was more accurate for the left circumflex than for the left anterior descending coronary artery territories (95% vs. 86%, P=0.01). Differences were not significant between BP AQ and cardiac MRI WM for discriminating normal from abnormal LV segments (McNemar difference, 3.2%; P=0.14).
AQ BP-gated SPECT assessment of regional and global LV WM agrees with independent cardiac MRI calculations and is superior to visual analysis for detecting regional WM abnormalities.
血池（BP）门控单光子发射计算机断层扫描（SPECT）应能够检测局部左心室（LV）功能障碍，因为该模式是全三维的，能够分辨所有心腔。本研究调查了这样一个假设：在心脏磁共振成像（MRI）扫描中出现局部壁运动（WM）异常的左心室节段，通过对BP数据进行全自动定量分析（AQ）计算出的BP局部射血分数（EF）也会异常。
本回顾性研究纳入了34例因冠心病接受评估的患者，这些患者通过回顾BP电影和心脏MRI评估对WM进行了视觉评估。将这些患者的心脏MRI值与一个包含10名健康志愿者的年龄匹配队列的心脏MRI值的机构数据库进行比较。一种AQ算法在BP断层图像上分割左心室血池，并将体积细分为17个亚区域。对每个左心室亚体积的计数与时间曲线拟合为三阶傅里叶级数，以计算局部EF。对于心脏MRI数据，在跨越整个心脏的11 - 13个短轴断层图像的60度样本上手动绘制心内膜和心外膜，从中计算局部WM值并重新划分为17个传统左心室节段。
AQ计算的整体EF范围为12%至75%，心脏MRI计算的范围为14%至75%（Pearson相关系数 = 0.95，P < 0.0001）。在识别12例整体EF小于35%的患者（McNemar差异，3%；P = 1.0）和19例EF小于50%的患者（差异，3%；P = 1.0）方面，BP AQ与心脏MRI之间的差异不显著。在识别心脏MRI WM异常的左心室节段方面，BP AQ比视觉评估更准确（受试者操作特征曲线下面积，88%对80%，P < 0.0001），并且在左旋支冠状动脉区域比左前降支冠状动脉区域更准确（95%对86%，P = 0.01）。在区分正常与异常左心室节段方面，BP AQ与心脏MRI WM之间的差异不显著（McNemar差异，3.2%；P = 0.14）。
AQ BP门控SPECT对局部和整体左心室WM的评估与独立的心脏MRI计算结果一致，并且在检测局部WM异常方面优于视觉分析。
