Wei Zhonghai, Bai Jian, Dai Qing, Wu Han, Qiao Shuaihua, Xu Biao, Wang Lian
Department of Cardiology, Drum Tower Hospital, Medical School of Nanjing University, 321 Zhongshan Road, Nanjing, 210008, Jiangsu Province, China.
BMC Cardiovasc Disord. 2018 Oct 1;18(1):188. doi: 10.1186/s12872-018-0924-z.
Shock index(SI) is a conventional predictive marker for haemodynamic state. Its breakpoint varies by different conditions according to previous studies. The current study was performed to evaluate the capability of SI in prediction of cardiogenic shock(CS) developed during primary percutaneous coronary intervention (pPCI).
Total 870 patients of ST segment elevation myocardial infarction(STEMI) who were haemodynamic stable before pPCI were involved in the study. In this cohort, 625 consecutive patients composed analysis series and 245 consecutive patients composed validation series. Multivariate regression analysis was used to evaluate whether SI was a significant predictor of developed CS and Hosmer-Lemeshow test was used to assess the goodness of model fitness. Receiver-operating characteristics (ROC) analysis was used to compare the predictive capability of SI with other predictors. The sensitivity, specificity, accuracy, positive and negative predictive values of SI at different cutoff values was compared to identify a best breakpoint.
In the analysis series, SI and Killips classification were identified as independent predictors. ROC analysis demonstrated the diagnostic capability of SI was superior to pre-procedural systolic blood pressure(SBP) or heart rate(HR) alone (0.8113 vs 0.7582, P = 0.04 and 0.8113 vs 0.7111, P < 0.001). The diagnostic capability of SI was equivalent to that of combination of SBP, HR and Killips claasification(0.8133 vs 0.8137, P = 0.97). SI had a high specificity and low sensitivity. When the cutoff value was set at 0.93, the positive predictive value, negative predictive value and diagnostic accuracy was 42.6%, 95.1% and 87.4% respectively. In validation series, the area under ROC curve was 0.8245, which was similar to that in the analysis series. The positive predictive value, negative predictive value and diagnostic accuracy at the cutoff value of 0.93 was 53.8%, 93.2% and 88.9% respectively.
SI has a high predictive accuracy for developing CS during pPCI in STEMI patients. It is an excellent exclusion diagnosis index rather than confirmative diagnosis index.
休克指数（SI）是血流动力学状态的传统预测指标。根据以往研究，其临界值因不同情况而异。本研究旨在评估SI预测直接经皮冠状动脉介入治疗（pPCI）期间发生的心源性休克（CS）的能力。
本研究纳入了870例在pPCI前血流动力学稳定的ST段抬高型心肌梗死（STEMI）患者。在这个队列中，625例连续患者组成分析系列，245例连续患者组成验证系列。采用多因素回归分析评估SI是否为发生CS的显著预测指标，并采用Hosmer-Lemeshow检验评估模型拟合优度。采用受试者操作特征（ROC）分析比较SI与其他预测指标的预测能力。比较SI在不同临界值时的敏感性、特异性、准确性、阳性预测值和阴性预测值，以确定最佳临界值。
在分析系列中，SI和Killips分级被确定为独立预测指标。ROC分析表明，SI的诊断能力优于术前收缩压（SBP）或心率（HR）单独使用时（0.8113对0.7582，P = 0.04；0.8113对0.7111，P < 0.001）。SI的诊断能力与SBP、HR和Killips分级联合使用时相当（0.8133对0.8137，P = 0.97）。SI具有高特异性和低敏感性。当临界值设定为0.93时，阳性预测值、阴性预测值和诊断准确性分别为42.6%、95.1%和87.4%。在验证系列中，ROC曲线下面积为0.8245，与分析系列相似。在临界值为0.93时，阳性预测值、阴性预测值和诊断准确性分别为53.8%、93.2%和88.9%。
SI对STEMI患者pPCI期间发生CS具有较高的预测准确性。它是一个优秀的排除诊断指标，而非确诊诊断指标。
