Department of Cardiology, University of Missouri-Kansas City (M.T., B.W.S., P.P.-O., A.O.M., A.I.M., I.M.S., P.S.C., J.A.S., R.C.T., T.M.B., K.K.P.).
Department of Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, MO (M.T., B.W.S., P.P.-O., A.O.M., A.I.M., P.S.C., J.A.S., R.C.T., T.M.B., K.K.P.).
Circ Cardiovasc Imaging. 2021 Oct;14(10):e012426. doi: 10.1161/CIRCIMAGING.121.012426. Epub 2021 Oct 19.
Rubidium-82 positron emission tomography myocardial perfusion imaging provides measurements of perfusion, myocardial blood flow and reserve (MBFR), and changes in left ventricular ejection fraction (LVEF) at rest and peak stress. Although all of these variables are known to provide prognostic information, they have not been well studied in patients with heart failure due to reduced LVEF.
Between 2010 and 2016, 1255 consecutive unique patients with LVEF≤40% were included in this study who underwent rubidium-82 positron emission tomography myocardial perfusion imaging and did not have subsequent revascularization within 90 days. Perfusion assessment was scored semiquantitatively, and LVEF reserve (stress-rest LVEF) and global MBFR (stress/rest MBF) were quantified using automated software. Cox proportional hazards models adjusted for 14 clinical and 7 test characteristics were used to define the independent prognostic significance of MBFR on all-cause mortality.
Of 1255 patients followed for a mean of 3.2 years, 454 (36.2%) died. After adjusting for clinical variables, the magnitude of fixed and reversible perfusion defects was prognostic of death (=0.02 and 0.01, respectively), while the rest LVEF was not (=0.18). The addition of LVEF reserve did not add any incremental value, while the addition of MBFR revealed incremental prognostic value (hazard ratio per 0.1 unit decrease in MBFR=1.08 [95% CI, 1.05-1.11], <0.001) with fixed and reversible defects becoming nonsignificant (=0.07 and 0.29, respectively). There was no interaction between MBFR and cause of cardiomyopathy (ischemic versus nonischemic).
In patients with a known cardiomyopathy who did not require early revascularization, reduced MBFR as obtained by positron emission tomography myocardial perfusion imaging is associated with all-cause mortality while other positron emission tomography myocardial perfusion imaging measures were not.
锶-82 正电子发射断层扫描心肌灌注成像可提供灌注、心肌血流和储备（MBFR）的测量值，以及静息和峰值应激时左心室射血分数（LVEF）的变化。尽管所有这些变量都已知提供预后信息，但在由于 LVEF 降低而导致心力衰竭的患者中，它们尚未得到很好的研究。
在 2010 年至 2016 年间，本研究共纳入 1255 例连续的 LVEF≤40%的独特患者，这些患者接受了锶-82 正电子发射断层扫描心肌灌注成像检查，并且在 90 天内没有进行后续血运重建。灌注评估采用半定量评分，使用自动软件定量评估 LVEF 储备（应激-静息 LVEF）和整体 MBFR（应激-静息 MBF）。使用 Cox 比例风险模型调整了 14 个临床和 7 个检测特征，以确定 MBFR 对全因死亡率的独立预后意义。
在平均随访 3.2 年的 1255 例患者中，有 454 例（36.2%）死亡。在调整临床变量后，固定和可逆灌注缺陷的严重程度与死亡相关（=0.02 和 0.01），而静息 LVEF 则没有（=0.18）。LVEF 储备的增加没有增加任何附加值，而 MBFR 的增加则显示出递增的预后价值（每降低 0.1 单位 MBFR 的风险比为 1.08[95%CI，1.05-1.11]，<0.001），固定和可逆缺陷变得不显著（=0.07 和 0.29）。MBFR 与心肌病的病因（缺血性与非缺血性）之间没有相互作用。
在已知患有心肌病且不需要早期血运重建的患者中，正电子发射断层扫描心肌灌注成像获得的 MBFR 降低与全因死亡率相关，而其他正电子发射断层扫描心肌灌注成像测量值则没有。
