目的:虽然广泛用于心力衰竭(HF)患者的分类,左心室射血分数(LVEF)对预后的作用存在争议.我们假设超声心动图测量左心室正向输出,更能代表心脏血流动力学,可能会改善大量有收缩功能障碍的HF患者的风险预测。
方法:在指南推荐的治疗中,LVEF<50%的连续稳定HF患者接受超声心动图检查,包括对前向LV输出的评估(即低压流出道速度-时间积分[LVOT-VTI],每搏量指数[SVi],和心脏指数[CI])在6年内,选择并随访心脏和全因死亡的终点。
结果:在分析的1,509例患者中(71±12年,75%的男性,LVEF35±9%),328人(22%)在中位28个月(14-40)的随访中死亡,165(11%),其中用于心脏原因。在多元回归分析中,LVOT-VTI(<0.001),SVi(p<0.001),和CI(p<0.001),而不是LVEF(p>0.05),预测心脏和全因死亡。LVOT-VTI的最佳预后截止值,SVi,和CI是15厘米,38mL/m2,分别为2L/min/m2。将这些措施中的每一个添加到多变量风险模型中(包括临床,生物体液,和超声心动图标志物)改善了风险预测(p<0.001)。在远期LV输出的不同度量中,CI的准确性低于LVOT-VTI和SVi。
结论:超声心动图对前向左心室输出的评估改善了HF患者在较宽的LVEF谱中的风险预测,生物体液,和超声心动图预后标志物。
OBJECTIVE: Though widely used to classify heart failure (HF) patients, the prognostic role of left ventricular ejection fraction (LVEF) is debated. We hypothesized that the echocardiographic measures of forward LV output, being more representative of cardiac hemodynamics, may improve risk prediction in a large cohort of HF patients with systolic dysfunction.
METHODS: Consecutive stable HF patients with LVEF <50% on guideline-recommended therapies undergoing an echocardiography including the evaluation of forward LV output (i.e., LV outflow tract velocity-time integral [LVOT-VTI], stroke volume index [SVi], and cardiac index [CI]) over a 6-year period, were selected and followed-up for the endpoint of cardiac and all-cause death.
RESULTS: Among the 1,509 patients analyzed (71±12 years, 75% males, LVEF 35±9%), 328 (22%) died during a median 28-month (14-40) follow-up, 165 (11%) of which for cardiac causes. At multivariable regression analysis, LVOT-VTI (<0.001), SVi (p<0.001), and CI (p<0.001), but not LVEF (p>0.05), predicted cardiac and all-cause death. The optimal prognostic cut-offs for LVOT-VTI, SVi, and CI were 15 cm, 38 mL/m2, and 2 L/min/m2, respectively. Adding each of these measures to a multivariable risk model (including clinical, biohumoral, and echocardiographic markers) improved risk prediction (p<0.001). Among the different measures of forward LV output, CI was less accurate than LVOT-VTI and SVi.
CONCLUSIONS: The echocardiographic evaluation of forward LV output improves risk prediction in HF patients across a wide LVEF spectrum over other well-established clinical, biohumoral, and echocardiographic prognostic markers.