Badgett R G, Mulrow C D, Otto P M, Ramírez G
Department of Medicine, University of Texas Health Science Center at San Antonio 78284-7879, USA.
J Gen Intern Med. 1996 Oct;11(10):625-34. doi: 10.1007/BF02599031.
To review the diagnostic utility of the chest radiograph for left ventricular dysfunction.
Structured MEDLINE searches, citation reviews of relevant primary research, review articles, and textbooks, personal files, and data from experts.
Studies of patients without valvular disease that allowed calculation of the sensitivity and specificity of selected radiographic signs compared with a criterion standard of increased left ventricular preload or reduced ejection fraction.
Two independent readers reviewed 29 studies. Studies were pooled after stratification by radiographic finding, criterion standard, and clinical setting.
Redistribution best diagnosed increased preload with a sensitivity of 65% (95% confidence interval [CI] 55%, 75%) and specificity 67% (95% CI 53%, 79%). Cardiomegaly best diagnosed decreased ejection fraction with a sensitivity of of 51% (95% CI 43%, 60%) and specificity of 79% (95% CI 71%, 85%). Interrater reliability was fair to moderate for redistribution and moderate for cardiomegaly. The clinical setting affected results by decreasing the specificity of cardiomegaly to 8% in detecting increased preload in patients with severe systolic dysfunction. The absence of redistribution could only exclude increased preload in situations in which the suspicion (pretest probability) of disease was less than 9%, whereas redistribution could confirm increased preload when the pretest probability was greater than 91%. The absence of cardiomegaly could only exclude a reduced ejection fraction if the pretest probability was less than 8%, whereas cardiomegaly could confirm a reduced ejection fraction if the pretest probability was greater than 87%.
Redistribution and cardiomegaly are the best chest radiographic findings for diagnosing increased preload and reduced ejection fraction, respectively. Unfortunately, neither finding alone can adequately exclude or confirm left ventricular dysfunction in usual clinical settings. Redistribution is not always reliably interpreted.
评估胸部X线片对左心室功能障碍的诊断价值。
结构化医学文献数据库检索、相关原始研究的引文综述、综述文章、教科书、个人档案以及专家提供的数据。
对无瓣膜疾病患者的研究，这些研究允许将所选X线征象的敏感性和特异性与左心室前负荷增加或射血分数降低的标准对照进行计算。
两名独立的研究者对29项研究进行了评估。研究在根据X线表现、标准对照和临床情况分层后进行汇总。
肺血重新分布对诊断前负荷增加的最佳敏感性为65%（95%置信区间[CI] 55%，75%），特异性为67%（95% CI 53%，79%）。心脏增大对诊断射血分数降低的最佳敏感性为51%（95% CI 43%，60%），特异性为79%（95% CI 71%，85%）。对于肺血重新分布，观察者间信度为中等；对于心脏增大，观察者间信度为中等。临床情况会影响结果，在检测重度收缩功能障碍患者的前负荷增加时，心脏增大的特异性降至8%。肺血无重新分布仅在疾病可疑（验前概率）小于9%的情况下才能排除前负荷增加，而当验前概率大于91%时，肺血重新分布可确诊前负荷增加。心脏无增大仅在验前概率小于8%时才能排除射血分数降低，而当验前概率大于87%时，心脏增大可确诊射血分数降低。
肺血重新分布和心脏增大分别是诊断前负荷增加和射血分数降低的最佳胸部X线表现。遗憾的是，在常规临床情况下，单独任何一项表现都不能充分排除或确诊左心室功能障碍。肺血重新分布的解读并不总是可靠的。
