Department of Internal Medicine, University of Pavia and IRCCS Ospedale San Matteo, Pavia, Italy.
Int J Cardiol. 2013 Aug 20;167(4):1170-5. doi: 10.1016/j.ijcard.2012.03.115. Epub 2012 Apr 13.
Predicting the occurrence of syncope in advance during tilt test could be useful to prepare the medical staff in preventing complications connected with this procedure, particularly in patients with no pre-syncopal symptoms. Our objective was to develop a simple algorithm able to predict the onset of neuromediated syncope during the tilt test.
We analysed the trend in RR interval, blood pressures, the ratio of these two variables and their derivative, as possible predictors of neuromediated syncope during tilt test. We studied 145 patients: 72 tilt test positive (age 7-82 years, 23 male, 49 female) and 73 tilt test negative (age 8-82 years, 36 male, 37 female), coming at our attention for suspected syncope. We evaluated time of prediction, sensitivity, specificity and receiver-operating curves (ROC) of the trends in RR interval, blood pressure, their ratio and the derivative of their ratio, in predicting syncope.
The derivative of the ratio between RR interval and systolic blood pressure (dRR/SBP) was able to predict syncope 44.1 ± 6.6s in advance with a sensitivity of 86.2% and a specificity of 89.1%. Area under the curve of ROC was 0.877 (p<0.001). The method was able to predict syncope in all three forms of neuromediated syncope: cardioinhibitory, mixed and vasodepressor. Similar results were found using the pulse pressure (dRR/PP).
Using dRR/SBP or dRR/PP it is possible to predict the occurrence of syncope in advance during tilt test.
在倾斜试验中提前预测晕厥的发生有助于医务人员准备预防与该程序相关的并发症，特别是在没有先兆晕厥症状的患者中。我们的目的是开发一种简单的算法，能够预测倾斜试验中神经介导性晕厥的发作。
我们分析了 RR 间期、血压、这两个变量的比值及其导数的趋势，作为倾斜试验中神经介导性晕厥的可能预测指标。我们研究了 145 例患者：72 例倾斜试验阳性（年龄 7-82 岁，23 例男性，49 例女性）和 73 例倾斜试验阴性（年龄 8-82 岁，36 例男性，37 例女性），因疑似晕厥而引起我们的注意。我们评估了 RR 间期、血压、它们的比值及其比值导数的趋势预测晕厥的预测时间、敏感性、特异性和接收者操作特征（ROC）曲线。
RR 间期与收缩压比值的导数（dRR/SBP）能够提前 44.1±6.6s 预测晕厥，敏感性为 86.2%，特异性为 89.1%。ROC 曲线下面积为 0.877（p<0.001）。该方法能够预测所有三种神经介导性晕厥的晕厥：心脏抑制型、混合性和血管抑制型。使用脉搏压（dRR/PP）也得到了类似的结果。
使用 dRR/SBP 或 dRR/PP 可以在倾斜试验中提前预测晕厥的发生。
