Abedi Seyed Mohammad, Ghadirzadeh Erfan, Karimi Hanie, Nezhadnaderi Pedram, Daryabari Seyede Sepide, Moradi Amir, Khorrami Moghaddam Alireza, Hosseinimehr Seyed Jalal, Taghavi Morteza, Golshani Samad, Farsavian Ali Asghar, Mardanshahi Alireza, Mostafavinia Ali
Department of Radiology and Nuclear Medicine, Faculty of Medicine, Cardiovascular Research Center, Mazandaran University of Medical Sciences, 4818813371 Sari, Iran.
Cardiovascular Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
Eur Heart J Imaging Methods Pract. 2024 Dec 24;3(1):qyae142. doi: 10.1093/ehjimp/qyae142. eCollection 2025 Jan.
While most clinical guidelines recommend using a 64-projection view technique, some protocols do not specify a preference between 32-projection and 64-projection methods for conducting myocardial perfusion scintigraphy (MPS), which shows the lack of consensus in this matter. Nevertheless, these guidelines and protocols have not provided us with compelling evidence to support why the 64-projection technique is usually chosen. Thus, we aimed to determine if there is a significant difference between them in the assessment of cardiac perfusion and functional indices.
Sixty-nine patients were included in this pilot prospective, cross-sectional, cross-over, same patient control protocol study and underwent 32- and 64-projection MPS at both stress and rest phases after injecting 740-925 MBq of 99mTc-MIBI for every patient. Then, cardiac indices, including summed stress, rest, and difference scores, extent-stress and rest, left ventricular volumes and ejection-fraction, peak filling rate (PFR), and time to peak filling rate (TTPF) were recorded. Lin's concordance correlation coefficient was used to assess the agreement between protocols, and a paired sample -test was used to compare the means of variables where appropriate. Findings revealed no significant difference as well as excellent/good agreement between the two methods in either the stress or rest state, except for the TTPF and PFR.
The findings suggest that lower-projection techniques could be adequate for routine clinical assessments without sacrificing diagnostic accuracy. However, the poor agreement for PFR and TTPF indicates that the 32-projection method may not reliably assess diastolic function, implying that the 64-projection protocol is preferable when precise evaluations are necessary.
虽然大多数临床指南推荐使用64投影视图技术，但一些方案并未明确指出在进行心肌灌注闪烁显像（MPS）时32投影法和64投影法之间的偏好，这表明在此问题上缺乏共识。然而，这些指南和方案并未为我们提供令人信服的证据来支持为何通常选择64投影技术。因此，我们旨在确定它们在评估心脏灌注和功能指标方面是否存在显著差异。
本前瞻性、横断面、交叉、同患者对照的初步研究纳入了69例患者，每位患者注射740 - 925 MBq的99mTc - MIBI后，在负荷和静息阶段分别接受32投影和64投影的MPS检查。然后，记录心脏指标，包括负荷、静息和差值总和评分、负荷和静息范围、左心室容积和射血分数、峰值充盈率（PFR）以及达到峰值充盈率的时间（TTPF）。使用林氏一致性相关系数评估方案之间的一致性，并在适当情况下使用配对样本t检验比较变量的均值。结果显示，除TTPF和PFR外，两种方法在负荷或静息状态下均无显著差异，且一致性良好/优秀。
研究结果表明，较低投影技术在不牺牲诊断准确性的情况下，可能足以用于常规临床评估。然而，PFR和TTPF的一致性较差表明，32投影法可能无法可靠地评估舒张功能，这意味着在需要精确评估时，64投影方案更可取。
