QT间期离散度预测冠心病室性心动过速的临床意义分析

Clinical analysis of QT interval dispersion in predicting susceptibility to ventricular tachycardia in patients with coronary heart disease

目的 探讨冠心病患者QT间期离散度 (QTD)值在预测持续性室性心动过速 (室速 )发生方面的临床意义。方法 以程序刺激法诱发室速 ,比较室速诱发成功组 (室速组 )和室速诱发未成功组 (非室速组 )体表心电图QTD值的改变并与心室晚电位 (VLP)检测结果作比较。结果 室速组QTD明显大于非室速组 [(76± 34)ms和 (49± 2 3)ms,P <0 0 1];QTD≥ 70ms预测室速的敏感性及阴性预测值明显高于VLP阳性 (6 6 7%和 5 0 0 % ,P <0 0 1;72 7%和 6 4 7% ,P <0 0 5 ) ,特异性及阳性预测值和VLP阳性相似 (91 4 %和 94 3% ,P >0 0 5 ;88 9%和 90 0 % ,P >0 0 5 ) ;如将QTD≥ 70ms和VLP阳性结合起来考虑则可获得较单一指标满意的预测价值。结论 QTD≥

Objective To analyze the clinical importance of QT interval dispersion (QTD) in predicting the susceptibility to sustained ventricular tachycardia in patients with coronary heart disease. Methods Dividing 71 patients into inducible ventricular tachycardia (VT) and noninducible ventricular tachycardia (Non VT) using programmed electrophysiologic testing, the changes of QTD in 2 groups were observed and compared with positive ventricular late potential (VLP). Result The QTD was significantly longer in patients with inducible VT than that in those with noninducible VT [(76±34)ms vs (49±23)ms,P<0 01)]; QTD of ≥70ms had a higher sensitivity and negative predictive valve than positive VLP (66 7% vs 50 0%, P<0 01; 72 7% vs 64 7%, P<0 05), but a similar specificity and positive predictive valve to positive VLP (91 4% vs 94 3%, P>0 05; 88 9% vs 90 0%, P>0 05) for inducible VT; Utility of QTD≥70ms combined with positive VLP had a more satisfied outcome than using either of these abnormalities in predicting inducible VT. Conclusion QTD is an easily measurable electrocardiographic index for predicting coronary heart disease.