Departments of Medicine (Division of Artificial Intelligence in Medicine), Imaging, and Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA, 90048, USA.
Department of Cardiology, Nihon University, Tokyo, Japan.
Eur J Nucl Med Mol Imaging. 2023 Oct;50(12):3619-3629. doi: 10.1007/s00259-023-06323-z. Epub 2023 Jul 10.
Phase analysis can assess left ventricular dyssynchrony. The independent prognostic value of phase variables over positron emission tomography myocardial perfusion imaging (PET-MPI) variables including myocardial flow reserve (MFR) has not been studied. The aim of this study was to explore the prognostic value of phase variables for predicting mortality over standard PET-MPI variables.
Consecutive patients who underwent pharmacological stress-rest Rb PET study were enrolled. All PET-MPI variables including phase variables (phase entropy, phase bandwidth, and phase standard deviation) were automatically obtained by QPET software (Cedars-Sinai, Los Angeles, CA). Cox proportional hazard analyses were used to assess associations with all-cause mortality (ACM).
In a total of 3963 patients (median age 71 years; 57% male), 923 patients (23%) died during a median follow-up of 5 years. Annualized mortality rates increased with stress phase entropy, with a 4.6-fold difference between the lowest and highest decile groups of entropy (2.6 vs. 12.0%/year). Abnormal stress phase entropy (optimal cutoff value, 43.8%) stratified ACM risk in patients with normal and impaired MFR (both p < 0.001). Among three phase variables, only stress phase entropy was significantly associated with ACM after the adjustment of standard clinical and PET-MPI variables including MFR and stress-rest change of phase variables, whether modeled as binary variables (adjusted hazard ratio, 1.44 for abnormal entropy [> 43.8%]; 95%CI, 1.18-1.75; p < 0.001) or continuous variables (adjusted hazard ratio, 1.05 per 5% increase; 95%CI, 1.01-1.10; p = 0.030). The addition of stress phase entropy to the standard PET-MPI variables significantly improved the discriminatory power for ACM prediction (p < 0.001), but the other phase variables did not (p > 0.1).
Stress phase entropy is independently and incrementally associated with ACM beyond standard PET-MPI variables including MFR. Phase entropy can be obtained automatically and included in clinical reporting of PET-MPI studies to improve patient risk prediction.
相位分析可评估左心室不同步。相位变量对正电子发射断层扫描心肌灌注成像（PET-MPI）变量（包括心肌血流储备（MFR））的独立预后价值尚未得到研究。本研究的目的是探讨相位变量预测死亡率的预后价值，超过标准的 PET-MPI 变量。
连续入组接受药物应激-静息 Rb PET 研究的患者。所有 PET-MPI 变量，包括相位变量（相位熵、相位带宽和相位标准差），均由 QPET 软件（Cedars-Sinai，洛杉矶，CA）自动获得。Cox 比例风险分析用于评估与全因死亡率（ACM）的相关性。
共 3963 例患者（中位年龄 71 岁；57%为男性），中位随访 5 年期间 923 例（23%）患者死亡。年度死亡率随应激相位熵增加而增加，熵值最低和最高十分位数组之间存在 4.6 倍差异（2.6%与 12.0%/年）。异常应激相位熵（最佳截断值为 43.8%）在 MFR 正常和受损的患者中分层 ACM 风险（均 p<0.001）。在三个相位变量中，仅应激相位熵在调整包括 MFR 和应激-静息相位变量变化在内的标准临床和 PET-MPI 变量后与 ACM 显著相关，无论是作为二分类变量（校正风险比，异常熵[>43.8%]的 1.44；95%CI，1.18-1.75；p<0.001）还是连续变量（校正风险比，每增加 5%的 1.05；95%CI，1.01-1.10；p=0.030）。将应激相位熵添加到标准 PET-MPI 变量中可显著提高 ACM 预测的区分能力（p<0.001），但其他相位变量则不然（p>0.1）。
应激相位熵与包括 MFR 在内的标准 PET-MPI 变量独立且递增相关，与 ACM 相关。相位熵可以自动获得，并包含在 PET-MPI 研究的临床报告中，以提高患者风险预测。
