Ebert T J, Eckberg D L, Vetrovec G M, Cowley M J
Cardiovasc Res. 1984 Jun;18(6):354-60. doi: 10.1093/cvr/18.6.354.
Linear regression was used to compare stroke volumes calculated from tetrapolar impedance cardiograms and simultaneous left ventriculograms in 14 patients undergoing diagnostic left heart catheterisation. We calculated three to five consecutive stroke volumes from each ventriculogram. Left ventricular stroke volumes estimated by the two methods correlated closely: the correlation coefficients from pairs of data obtained from individual patients ranged between 0.77 and 1.00 (average = 0.91), and the correlation coefficient for pooled data (all pairs from all subjects) was 0.79 (p less than 0.001). Changes in left ventricular stroke volume measured with the two methods also correlated well (r = 0.89 for pooled data, p less than 0.001). The results suggest that impedance cardiograms provide reliable estimates of changes of beat-by-beat left ventricular stroke volumes and reasonable estimates of absolute levels of beat-by-beat stroke volumes in humans.
采用线性回归法，比较了14例接受诊断性左心导管检查患者的四极阻抗心动图和同步左心室造影所计算出的每搏输出量。我们从每个心室造影中计算出三到五个连续的每搏输出量。两种方法估算的左心室每搏输出量密切相关：从个体患者获得的成对数据的相关系数在0.77至1.00之间（平均=0.91），汇总数据（所有受试者的所有成对数据）的相关系数为0.79（p<0.001）。两种方法测量的左心室每搏输出量变化也具有良好的相关性（汇总数据的r=0.89，p<0.001）。结果表明，阻抗心动图能够可靠地估算人体逐搏左心室每搏输出量的变化，并能合理地估算逐搏每搏输出量的绝对水平。
