Abstract:
Objective To explore the feasibility of quantitative analysis in 99Tcm-methoxyisobutylisonitrile (MIBI)/123I-metaiodobenzylguanidine (MIBG) dual-isotope and dual-dynamic cardiac imaging using cadmium zinc telluride (CZT) SPECT.
Methods Twenty-four patients (14 males and 10 females) aged (49.2±16.8) years with cardiac dysfunction were prospectively enrolled from October 2021 to June 2023 at Fuwai Hospital, Chinese Academy of Medical Sciences. All the patients underwent 99Tcm-MIBI single-isotope dynamic cardiac imaging (referred to as single-isotope imaging) on the first day and 99Tcm-MIBI/123I-MIBG dual-isotope dual-dynamic cardiac imaging (referred to as dual-isotope imaging) on the second day. And complete physical correction and incomplete-physical correction were performed. Myocardial blood flow (MBF) for left ventricle (LV), left anterior descending branch (LAD), left circumflex branch (LCX), and right coronary artery (RCA) dominant area was quantified. Differences, correlation, and agreement of these parameters from two imaging methods were analyzed using Wilcoxon rank sum test, Pearson correlation test, and Bland-Altman analysis.
Results The MBF of LV and LAD, LCX, RCA dominant area of single-isotope imaging and dual-isotope imaging with complete physical correction were 0.74 (0.64, 0.79) ml·min−1·g−1 vs. 0.74 (0.64, 0.80) ml·min−1·g−1, 0.72 (0.68, 0.82) ml·min−1·g−1 vs. 0.74 (0.64, 0.84) ml·min−1·g−1, 0.73 (0.66, 0.80) ml·min−1·g−1 vs. 0.74 (0.61, 0.79) ml·min−1·g−1, and 0.77 (0.64, 0.82) ml·min−1·g−1 vs. 0.77 (0.66, 0.82) ml·min−1·g−1, respectively. The differences were not statistically significant (Z=−1.349, −0.396, −0.350, −1.126; all P>0.05). The MBF of LV and LAD, LCX, RCA dominant area between single-isotope imaging and dual-isotope imaging with complete physical correction showed good correlations (r=0.857, 0.832, 0.708, 0.815; all P<0.001). The MBF mean differences of LV and LAD, LCX, RCA dominant area between single-isotope imaging and dual-isotope imaging with complete physical correction were 0.023, 0.016, 0.008, 0.040 ml·min−1·g−1, and the 95% confidence intervals were −0.125 to 0.170, −0.196 to 0.228, −0.181 to 0.196, and −0.193 to 0.271, respectively. The agreement between the two acquisition methods was good.
Conclusions CZT-SPECT can be used to obtain comparable MBF between single-isotope imaging and dual-isotope cardiac imaging on the basis of complete physical correction. It is feasible to conduct a quantitative analysis of MBF and cardiac sympathetic nervous system through a single examination.