经食管超声心动图通过连续波多普勒测量主动脉瓣处的心输出量。

Cardiac output by transesophageal echocardiography using continuous-wave Doppler across the aortic valve.

作者信息

Darmon P L, Hillel Z, Mogtader A, Mindich B, Thys D

机构信息

Department of Anesthesiology, St. Luke's-Roosevelt Hospital Center, College of Physicians and Surgeons, Columbia University, New York, New York 10025.

出版信息

Anesthesiology. 1994 Apr;80(4):796-805; discussion 25A. doi: 10.1097/00000542-199404000-00011.

DOI:10.1097/00000542-199404000-00011

PMID:8024133

Abstract

BACKGROUND

The use of transesophageal echocardiography for the determination of cardiac output (CO) has been limited to date. We assessed the capability of aortic continuous-wave Doppler transesophageal echocardiography to determine CO (DCO) in a transgastric long-axis imaging plane of the heart by comparing DCO to thermodilution CO (TCO).

METHODS

DCO was determined in 63 consecutive patients undergoing cardiac surgery. Aortic valve area was obtained from the transverse short-axis view of the valve assuming a triangular shape for the valve orifice. Stroke volume was calculated as the product of velocity-time integral and aortic valve area: stroke volume = velocity-time integral x aortic valve area. DCO was calculated off-line, by multiplying stroke volume with heart rate: DCO = stroke volume x heart rate.

RESULTS

The aortic valve orifice was easily imaged in all patients. Excellent-quality continuous-wave Doppler flow profiles were obtained in nearly all (62 of 63). A total of 109 DCO determinations were performed. Mean DCO was 4.35 +/- 1.18 l.min-1 (range 2.02-7.42 l.min-1), and mean TCO was 4.41 +/- 1.17 l.min-1 (range 2.24-8.94 l.min-1). Very high correlation and agreement were found between the two methods: DCO = 0.94 x TCO + 0.19, r = 0.94, SEE (standard error of the estimate) = 0.41 l.min-1; 95% confidence interval = 0.06 +/- 0.83 l.min-1. Relative changes from pre- to postbypass CO (delta) also showed a strong correlation (delta DCO = 0.93 x delta TCO + 5.4%, r = 0.82, SEE = 17.8%). For CO changes greater than 10%, Doppler was in accordance with thermodilution in 43 of 45 measurements. DCO repeatability coefficient was 0.51 l.min-1.

CONCLUSIONS

Compared to thermodilution, continuous-wave Doppler measurements of blood flow velocity across the aortic valve in the transesophageal echocardiographic transgastric view allow accurate CO determination.

摘要

背景

迄今为止，经食管超声心动图用于测定心输出量（CO）的应用一直有限。我们通过比较经胃长轴心脏成像平面中主动脉连续波多普勒经食管超声心动图测定的心输出量（DCO）与热稀释法测定的心输出量（TCO），评估了其测定CO的能力。

方法

对63例连续接受心脏手术的患者测定DCO。假设瓣膜口为三角形，从瓣膜的横向短轴视图获取主动脉瓣面积。每搏量计算为速度时间积分与主动脉瓣面积的乘积：每搏量 = 速度时间积分×主动脉瓣面积。DCO通过离线计算得出，即每搏量乘以心率：DCO = 每搏量×心率。

结果

所有患者的主动脉瓣口均易于成像。几乎所有患者（63例中的62例）均获得了高质量的连续波多普勒血流频谱。共进行了109次DCO测定。平均DCO为4.35±1.18 l.min⁻¹（范围2.02 - 7.42 l.min⁻¹），平均TCO为4.41±1.17 l.min⁻¹（范围2.24 - 8.94 l.min⁻¹）。两种方法之间发现了非常高的相关性和一致性：DCO = 0.94×TCO + 0.19，r = 0.94，估计标准误差（SEE） = 0.41 l.min⁻¹；95%置信区间 = 0.06±0.83 l.min⁻¹。体外循环前后CO的相对变化（δ）也显示出很强的相关性（δDCO = 0.93×δTCO + 5.4%，r = 0.82，SEE = 17.8%）。对于CO变化大于10%的情况，在45次测量中有43次多普勒测定结果与热稀释法一致。DCO的重复性系数为0.51 l.min⁻¹。