Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050000, China.
Am J Emerg Med. 2012 Sep;30(7):1089-94. doi: 10.1016/j.ajem.2011.07.009. Epub 2011 Oct 27.
The aim of this study was to evaluate the additional predictive value of serum potassium (SK) to Thrombolysis In Myocardial Infarction (TIMI) risk score for malignant ventricular arrhythmias (MVA) in patients within 24 hours of acute myocardial infarction (AMI).
This was a 6-year retrospective study. The receiver operating characteristic curve was used to evaluate the predictive value of SK and TIMI risk score for MVA attack. In addition, SK-modified TIMI risk score was created by incorporating SK information into the usual score; the accuracy of new score was compared with that of the usual TIMI risk score by comparing the area under the receiver operating characteristic curves (AUC).
Among the 468 patients enrolled, the incidence of MVA 24 hours after AMI was 9.4%, and it was higher in the hypokalemia group compared with that of the normokalemic group (27.3% vs 7.5%, P < .001; odds ratio, 4.594; 95% confidence interval [CI], 2.159-9.774). A significant predictive value of SK was indicated by AUC of 0.787 (95% CI, 0.747-0.823, P < .01). Serum potassium remained a predictor of MVA after being adjusted by the variables in TIMI risk score. The AUC of TIMI risk score in relation to MVA was 0.586 (95% CI, 0.54-0.631; P = .0676). The incorporation of SK into TIMI risk score improved its predictive value for MVA attack (AUC = 0.66; 95% CI, 0.568-0.753; P < .001), with significant difference between AUC of the new score and that of the original risk score (Z = 2.474, P = .013).
Serum potassium on admission to the emergency department may be used as a valuable predictor and could add predictive information to some extent to TIMI risk score for MVA attack during 24-hour post-AMI.
本研究旨在评估血清钾（SK）对急性心肌梗死（AMI）后 24 小时内恶性室性心律失常（MVA）的 Thrombolysis In Myocardial Infarction（TIMI）风险评分的额外预测价值。
这是一项为期 6 年的回顾性研究。采用受试者工作特征曲线评估 SK 和 TIMI 风险评分对 MVA 发作的预测价值。此外，通过将 SK 信息纳入常规评分，创建 SK 改良的 TIMI 风险评分；通过比较受试者工作特征曲线下面积（AUC）来比较新评分与常规 TIMI 风险评分的准确性。
在纳入的 468 例患者中，AMI 后 24 小时 MVA 的发生率为 9.4%，低钾血症组明显高于正常血钾组（27.3%比 7.5%，P<.001；优势比，4.594；95%置信区间[CI]，2.159-9.774）。AUC 为 0.787（95%CI，0.747-0.823，P<.01）表明 SK 具有显著的预测价值。在调整 TIMI 风险评分中变量后，SK 仍然是 MVA 的预测因子。TIMI 风险评分与 MVA 的 AUC 为 0.586（95%CI，0.54-0.631；P=0.0676）。将 SK 纳入 TIMI 风险评分可提高其对 MVA 发作的预测价值（AUC=0.66；95%CI，0.568-0.753；P<.001），新评分与原始风险评分的 AUC 存在显著差异（Z=2.474，P=0.013）。
入院时的血清钾可作为有价值的预测指标，在一定程度上可为 AMI 后 24 小时内的 TIMI 风险评分对 MVA 发作的预测提供补充信息。
