Romeo Francisco J, Seropian Ignacio M, Arora Sameer, Vavalle John P, Falconi Mariano, Oberti Pablo, Kotowicz Vadim, Agatiello Carla R, Berrocal Daniel H
Division of Interventional Cardiology, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
Division of Cardiology, University of North Carolina, Chapel Hill, NC, USA.
Cardiovasc Diagn Ther. 2020 Feb;10(1):12-23. doi: 10.21037/cdt.2019.05.02.
Myocardial contraction fraction (MCF), a volumetric measurement of myocardial shortening, may help to improve risk stratification in patients with severe aortic stenosis (AS) referred for transcatheter aortic valve replacement (TAVR) especially in those with preserved left ventricular ejection fraction (LVEF). We investigated the association between MCF and 1-year all-cause mortality in patients with severe AS who underwent TAVR.
MCF was calculated as the ratio of stroke volume (SV) to myocardial volume. Patients referred for TAVR from 2011 to 2015 were eligible for inclusion and were divided into two groups according to the estimated MCF (MCF ≤30% MCF >30%). The primary endpoint was 1-year all-cause mortality. A Cox regression analysis was performed for independent risk factors of mortality. Receiver operating curve (ROC) was performed for assessing the best cut-off point of MCF for predicting the primary outcome [area under the curve (AUC) 0.60; 95% confidence interval (CI): 0.453-0.725]. Baseline patient and echo characteristics were included for multivariate analysis.
Of 126 patients (mean age 82±5 years, 45.2% male), 44.4% showed MCF ≤30%. Patient with reduced MCF showed higher body mass index (28.1±5.8 26.0±4.5 kg/m, P=0.031), higher surgical EuroScore II (6.2±4.5 4.7±3.2, P=0.032), lower LVEF (54.2%±11.9% 58.5%±10.8%, P=0.042) and more severe AS (indexed aortic valve area 0.40±0.09 0.45±0.10 cm/m, P=0.030). The median follow-up was of 14 [3.5-33] months, and 16% of patients died. Patients with MCF ≤30% showed significantly increased all-cause mortality (Log-rank P=0.002). In a multivariate model adjusting for clinical and echo variables, MCF ≤30% was independently associated with increased risk for all-cause 1-year mortality [hazard ratio (HR) 2.76, 95% CI: 1.03-7.77, P=0.04].
In a population of patients undergoing TAVR, MCF ≤30% was independently associated with increased mortality.
心肌收缩分数（MCF）是一种心肌缩短的容积测量指标，可能有助于改善接受经导管主动脉瓣置换术（TAVR）的重度主动脉瓣狭窄（AS）患者的风险分层，尤其是左心室射血分数（LVEF）保留的患者。我们研究了接受TAVR的重度AS患者中MCF与1年全因死亡率之间的关联。
MCF计算为每搏量（SV）与心肌容积之比。2011年至2015年接受TAVR治疗的患者符合纳入标准，并根据估计的MCF（MCF≤30%与MCF>30%）分为两组。主要终点是1年全因死亡率。对死亡率的独立危险因素进行Cox回归分析。绘制受试者工作特征曲线（ROC）以评估MCF预测主要结局的最佳切点[曲线下面积（AUC）为0.60；95%置信区间（CI）：0.453-0.725]。纳入基线患者和超声心动图特征进行多变量分析。
126例患者（平均年龄82±5岁，男性占45.2%）中，44.4%的患者MCF≤30%。MCF降低的患者体重指数更高（28.1±5.8与26.0±4.5kg/m²，P=0.031），外科欧洲心脏手术风险评估系统（EuroScore）II评分更高（6.2±4.5与4.7±3.2，P=0.032），LVEF更低（54.2%±11.9%与58.5%±10.8%，P=0.042），AS更严重（主动脉瓣面积指数0.40±0.09与0.45±0.10cm²/m²，P=0.030）。中位随访时间为14[3.5-33]个月；16%的患者死亡。MCF≤30%的患者全因死亡率显著增加（对数秩检验P=0.002）。在调整临床和超声心动图变量的多变量模型中，MCF≤30%与1年全因死亡风险增加独立相关[风险比（HR）为2.76，95%CI：1.03-7.77，P=0.04]。
在接受TAVR的患者群体中，MCF≤30%与死亡率增加独立相关。
