Bing Rong, Gu Haotian, Chin Calvin, Fang Lingyun, White Audrey, Everett Russell J, Spath Nicholas B, Park Eunsoo, Jenkins William Sa, Shah Anoop Sv, Mills Nicholas L, Flapan Andrew D, Chambers John B, Newby David E, Chowienczyk Phil, Dweck Marc R
Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, UK
BHF Centre for Cardiovascular Sciences, The University of Edinburgh, Edinburgh, UK.
Heart. 2020 Aug;106(16):1236-1243. doi: 10.1136/heartjnl-2020-316684. Epub 2020 Apr 28.
First-phase ejection fraction (EF1) is a novel measure of early left ventricular systolic dysfunction. We investigated determinants of EF1 and its prognostic value in aortic stenosis.
EF1 was measured retrospectively in participants of an echocardiography/cardiovascular magnetic resonance cohort study which recruited patients with aortic stenosis (peak aortic velocity of ≥2 m/s) between 2012 and 2014. Linear regression models were constructed to examine variables associated with EF1. Cox proportional hazards were used to determine the prognostic power of EF1 for aortic valve replacement (AVR, performed as part of clinical care in accordance with international guidelines) or death.
Total follow-up of the 149 participants (69.8% male, 70 (65-76) years, mean gradient 33 (21-42) mm Hg) was 238 029 person-days. Sixty-seven participants (45%) had a low baseline EF1 (<25%) despite normal ejection fraction (67% (62%-71%)). Patients with low EF1 had more severe aortic stenosis (mean gradient 39 (34-45) mm Hg vs 24 (16-35) mm Hg, p<0.001) and more myocardial fibrosis (indexed extracellular volume (iECV) (24.2 (19.6-28.7) mL/m vs 20.6 (16.8-24.3) mL/m, p=0.002; late gadolinium enhancement (LGE) prevalence 52% vs 20%, p<0.001). Zva, iECV and infarct LGE were independent predictors of EF1. EF1 improved post-AVR (n=57 with post-AVR EF1 available, baseline 16 (12-24) vs follow-up 27% (22%-31%); p<0.001). Low baseline EF1 was an independent predictor of AVR/death (HR 5.6, 95% CI 3.4 to 9.4), driven by AVR.
EF1 quantifies early, potentially reversible systolic dysfunction in aortic stenosis, is associated with global afterload and myocardial fibrosis, and is an independent predictor of AVR.
首阶段射血分数（EF1）是一种评估早期左心室收缩功能障碍的新指标。我们研究了EF1的决定因素及其在主动脉瓣狭窄中的预后价值。
对一项超声心动图/心血管磁共振队列研究的参与者进行回顾性测量EF1，该研究在2012年至2014年期间招募了主动脉瓣狭窄（主动脉峰值流速≥2 m/s）患者。构建线性回归模型以检验与EF1相关的变量。采用Cox比例风险模型确定EF1对主动脉瓣置换术（AVR，按照国际指南作为临床治疗的一部分进行）或死亡的预后预测能力。
149名参与者（69.8%为男性，年龄70（65 - 76）岁，平均压力阶差33（21 - 42）mmHg）的总随访时间为238029人日。尽管射血分数正常（67%（62% - 71%）），但67名参与者（45%）的基线EF1较低（<25%）。EF1较低的患者主动脉瓣狭窄更严重（平均压力阶差39（34 - 45）mmHg对24（16 - 35）mmHg，p<0.001），心肌纤维化更明显（细胞外容积指数（iECV）（24.2（19.6 - 28.7）mL/m对20.6（16.8 - 24.3）mL/m，p = 0.002；延迟钆增强（LGE）患病率52%对20%，p<0.001）。左心室-动脉耦合指数（Zva）、iECV和梗死LGE是EF1的独立预测因素。AVR术后EF1有所改善（n = 57，有术后EF1数据，基线时为16%（12% - 24%），随访时为27%（22% - 31%）；p<0.001）。低基线EF1是AVR/死亡的独立预测因素（风险比5.6，95%置信区间3.4至9.4），主要由AVR驱动。
EF1可量化主动脉瓣狭窄早期潜在可逆的收缩功能障碍，与整体后负荷和心肌纤维化相关，是AVR的独立预测因素。
