Parrott Charles W, Burnham Kenneth M, Quale Cheryl, Lewis Deborah L
Cardiology Associates of Mobile, Providence Hospital, Heart Failure Clinic, Mobile, AL 36608, USA.
Congest Heart Fail. 2004 Mar-Apr;10(2 Suppl 2):11-3. doi: 10.1111/j.1527-5299.2004.03407.x.
Ejection fraction (EF) is the most common measure of left ventricular function in patients with heart failure. However, serial measurements of EF are costly and not practical for guiding frequent management decisions. Impedance cardiography (ICG) provides noninvasive hemodynamic measures with proven validity. The purpose of this study was to assess how changes in ICG parameters compared with changes in EF in heart failure subjects enrolled in a comprehensive outpatient management program. Retrospective chart review identified 13 subjects with two sets of paired echocardiography and ICG measurements (before and after treatment in an outpatient heart failure clinic setting). Mean age was 69+/-11 years, etiology was 54% ischemic heart disease, and mean New York Heart Association class was 2.5+/-0.5. The mean time between pre- and posttreatment EF measurements was 198+/-161 days. Changes in cardiac index and systolic time ratio by ICG were compared with changes in EF by echocardiography. From entry to final measurement, mean EF improved 9%+/-13%. Seven (54%) subjects had >5% improvement in EF, three (23%) had >5% decrease, and three had <5% change. Changes in ICG cardiac index and systolic time ratio were highly correlated with changes in EF (0.85, -0.73). ICG may be a practical, reliable, and cost-effective method of monitoring left ventricular function and guiding management decisions.
射血分数（EF）是心力衰竭患者左心室功能最常用的测量指标。然而，连续测量EF成本高昂，对于指导频繁的管理决策并不实用。阻抗心动图（ICG）可提供已证实有效的非侵入性血流动力学测量方法。本研究的目的是评估在参加综合门诊管理项目的心力衰竭受试者中，ICG参数变化与EF变化的比较情况。回顾性病历审查确定了13名受试者，他们有两组配对的超声心动图和ICG测量值（在门诊心力衰竭诊所环境中治疗前后）。平均年龄为69±11岁，病因是54%为缺血性心脏病，平均纽约心脏协会分级为2.5±0.5。治疗前和治疗后EF测量之间的平均时间为198±161天。将ICG测量的心脏指数和收缩时间比的变化与超声心动图测量的EF变化进行比较。从入组到最终测量，平均EF提高了9%±13%。7名（54%）受试者的EF改善>5%，3名（23%）受试者的EF下降>5%，3名受试者的EF变化<5%。ICG心脏指数和收缩时间比的变化与EF的变化高度相关（0.85，-0.73）。ICG可能是一种实用、可靠且具有成本效益的监测左心室功能和指导管理决策的方法。
