CMR对IQ-SPECT系统测量的小心脏大小患者左心室容积和射血分数的验证。

CMR validation of left ventricular volumes and ejection fraction measured by the IQ-SPECT system in patients with small heart size.

作者信息

Wei Hua, Wu Jiaojiao, Han Ke, Hu Guang, Wang Hongliang, Guo Xiaoshan, Liu Haiyan, Wu Zhifang, Li Sijin

机构信息

Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan, 030001, Shanxi, People's Republic of China.

Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Shanxi Medical University, Taiyuan, 030001, Shanxi, People's Republic of China.

出版信息

EJNMMI Res. 2023 Apr 24;13(1):33. doi: 10.1186/s13550-023-00987-2.

DOI:10.1186/s13550-023-00987-2

PMID:37093329

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10126186/

Abstract

BACKGROUND

The IQ-SPECT system is equipped with multifocal collimators and uses ordered-subset conjugate gradient minimization (OSCGM) as its reconstruction algorithm, achieving a shorter acquisition time than conventional SPECT. Left ventricular ejection fraction (LVEF) is overestimated by conventional SPECT in patients with small heart size. In this study, we compared IQ-SPECT with conventional SPECT and cardiovascular magnetic resonance (CMR) for the estimation of LVEF in patients with small hearts (males: EDV ≤ 60 ml, ESV ≤ 25 ml; females: EDV ≤ 45 ml, ESV ≤ 20 ml).

METHODS

The study consisted of 49 consecutive patients (20 normal and 29 with small heart size) undergoing gated myocardial perfusion imaging (GMPI) with a 99mTc-labelled agent during stress or rest to assess the risk of coronary artery disease (CAD). The data were reconstructed using filtered back-projection (FBP) for conventional SPECT and OSCGM for IQ-SPECT. ESV, EDV, and LVEF were calculated using quantitative gated SPECT (QGS). To determine the optimal ordered-subset reconstruction parameters, we compared the LVEF from SPECT to the corresponding measurement from CMR.

RESULTS

EDV, ESV, and LVEF values obtained from IQ-SPECT and conventional SPECT showed that the results of these two forms of SPECT were significantly correlated, although the EDV and ESV obtained by IQ-SPECT were higher than those obtained by conventional SPECT. IQ-SPECT yielded lower LVEF measurements than conventional SPECT (normal heart size: 50.6 ± 4.3% vs. 73.4 ± 8.4%, P = 0.002; small heart size: 62.1 ± 7.8% vs. 75.0 ± 11.4%, P < 0.001). There were no significant differences in LVEF measurements made by IQ-SPECT and CMR (normal heart size: 50.6 ± 4.3% vs. 53.2 ± 5.8%, P > 0.05; small heart size: 62.1 ± 7.8% vs. 64.6 ± 8.8%, P > 0.05). Five subsets (S) and 12 iterations (I) did not differ significantly in LVEF between CMR and IQ-SPECT for patients with small hearts (64.6 ± 8.8% vs. 62.1 ± 7.8%, P = 0.120), while 3 S and 10 I were the best parameters for patients with normal heart size (50.6 ± 4.3% vs. 53.1 ± 5.8%, P = 0.117).

CONCLUSION

With CMR as the standard, IQ-SPECT yields more reliable LVEF values than conventional SPECT for populations with small heart size. The best reconstruction parameters from IQ-SPECT were 5 S and 12 I for patients with small hearts.

摘要

背景

IQ-SPECT系统配备多焦点准直器，并使用有序子集共轭梯度最小化（OSCGM）作为其重建算法，与传统SPECT相比，采集时间更短。在心脏较小的患者中，传统SPECT会高估左心室射血分数（LVEF）。在本研究中，我们比较了IQ-SPECT与传统SPECT及心血管磁共振（CMR）在评估小心脏患者（男性：舒张末期容积[EDV]≤60 ml，收缩末期容积[ESV]≤25 ml；女性：EDV≤45 ml，ESV≤20 ml）LVEF方面的差异。

方法

本研究纳入49例连续患者（20例正常心脏和29例小心脏患者），这些患者在负荷或静息状态下接受了用99mTc标记剂进行的门控心肌灌注显像（GMPI），以评估冠状动脉疾病（CAD）风险。数据采用滤波反投影（FBP）重建传统SPECT图像，采用OSCGM重建IQ-SPECT图像。使用定量门控SPECT（QGS）计算ESV、EDV和LVEF。为确定最佳有序子集重建参数，我们将SPECT测得的LVEF与CMR相应测量值进行比较。

结果

IQ-SPECT和传统SPECT获得的EDV、ESV和LVEF值显示，这两种SPECT形式的结果显著相关，尽管IQ-SPECT获得的EDV和ESV高于传统SPECT。IQ-SPECT测得的LVEF低于传统SPECT（正常心脏大小：50.6±4.3%对73.4±8.4%，P = 0.002；小心脏大小：62.1±7.8%对75.0±11.4%，P < 0.001）。IQ-SPECT和CMR测得的LVEF无显著差异（正常心脏大小：50.6±4.3%对53.2±5.8%，P > 0.05；小心脏大小：62.1±7.8%对64.6±8.8%，P > 0.05）。对于小心脏患者，5个子集（S）和12次迭代（I）的IQ-SPECT与CMR之间的LVEF无显著差异（64.6±8.8%对62.1±7.8%，P = 0.120），而3 S和10 I是正常心脏大小患者的最佳参数（50.6±4.3%对53.1±5.8%，P = 0.117）。