Naik M M, Diamond G A, Pai T, Soffer A, Siegel R J
Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California 90048-0750.
J Am Coll Cardiol. 1995 Mar 15;25(4):937-42. doi: 10.1016/0735-1097(94)00506-L.
This study assessed the agreement of left ventricular ejection fraction determinations from two-dimensional echocardiography, radionuclide angiography and contrast cineangiography.
Previously published reports suggest that two-dimensional echocardiography, radionuclide angiography and contrast cineangiography are equally acceptable methods of assessing left ventricular ejection fraction on the basis of high coefficients of correlation. However, correlation of methods does not necessarily imply agreement.
In a prospective analysis, 25 consecutive subjects all had two-dimensional echocardiography and radionuclide angiography performed within 10 days of each other in the cardiology department of metropolitan community hospital. A retrospective computer search (Medline) revealed seven studies, using the coefficient of correlation (r), comparing two-dimensional echocardiographic left ventricular ejection fraction (n = 268) with radionuclide angiographic (n = 174) or contrast cineangiographic (n = 119) left ventricular ejection fractions.
The eight individual studies (n = 293) comparing two-dimensional echocardiography with either radionuclide angiography or contrast cineangiography exhibited coefficients of correlation ranging from 0.78 to 0.93. Agreement analysis using the method of Bland and Altman was performed by averaging the results obtained from the two techniques and determining how disparate any single ejection fraction was (with 95% confidence limits) from the mean value. Agreement ranged from 23% to 42% around the mean ejection fraction. The average lack of agreement between the two methods for all studies involved was 17%, with an average r value of 0.86.
Left ventricular ejection fraction determinations by means of two-dimensional echocardiography, radionuclide angiography and contrast cineangiography exhibit high correlation and only moderate agreement. High correlation does not always imply high agreement. These results suggest that, when validated by agreement analysis, multiple studies may not be necessary in appropriate clinical situations, potentially reducing costs.
本研究评估二维超声心动图、放射性核素血管造影和对比电影血管造影测定左心室射血分数的一致性。
先前发表的报告表明,基于高相关系数,二维超声心动图、放射性核素血管造影和对比电影血管造影是评估左心室射血分数同样可接受的方法。然而,方法之间的相关性并不一定意味着一致性。
在一项前瞻性分析中,25名连续入选的受试者在大都市社区医院心内科均于彼此间隔10天内接受了二维超声心动图和放射性核素血管造影检查。一项回顾性计算机检索(医学文献数据库)发现了7项研究,这些研究使用相关系数(r)比较二维超声心动图左心室射血分数(n = 268)与放射性核素血管造影(n = 174)或对比电影血管造影(n = 119)左心室射血分数。
八项比较二维超声心动图与放射性核素血管造影或对比电影血管造影的独立研究(n = 293)显示相关系数范围为0.78至0.93。采用布兰德和奥特曼方法进行一致性分析,即对两种技术获得的结果求平均值,并确定任何单个射血分数与平均值相差多少(95%置信区间)。围绕平均射血分数的一致性范围为23%至42%。所有研究中两种方法之间的平均不一致率为17%,平均r值为0.86。
通过二维超声心动图、放射性核素血管造影和对比电影血管造影测定左心室射血分数显示出高度相关性,但仅有中度一致性。高相关性并不总是意味着高度一致性。这些结果表明,经一致性分析验证后,在适当的临床情况下可能无需进行多项研究,从而有可能降低成本。