老年人急性心肌梗塞后心室颤动与QTc离散度关系的探讨

回顾性单盲分析老年人急性心肌梗塞发病２４小时内首次心电图ＱＴｃ离散度（ＱＴｃｄ）。心室颤动（简称室颤）组（ｎ＝１０）ＱＴｃｄ为７５．１±４５．２ｍｓ，非室颤组（ｎ＝６０）则为３２．０±１５．３ｍｓ，健康对照组（ｎ＝２０）为２７．２±７．１ｍｓ。室颤组与后两组比较，差异有高度显著性（Ｐ＜０．０１）。前壁心肌梗塞者（ｎ＝３０）ＱＴｃｄ为３６．３±３１．１ｍｓ，下壁心肌梗塞者（ｎ＝４０）则为３９．５±２２．５ｍｓ。ＱＴｃｄ≥４０ｍｓ２５例，发生室颤９例（３６％），而ＱＴｃｄ＜４０ｍｓ且ＱＴｃ＜４４０ｍｓ的２９例中，无一例发生室颤。结果提示老年人急性心肌梗塞后室颤的发生与ＱＴｃｄ明显增加有关。

Increased QTc Dispersion and Its Relation to Ventricular Fibrillation After Acute Myocardial Infarction in the Elderly

We retrospectively studied changes in QTc dispersion(QTcd)defined as QTcmax-QTcmin in the elderly with acute myocardial infarction(AMI)after symptom onset less than 24 hours. ECG analysis was performed by a single blined observer. QTcd was 75.1±45.2ms,32.0± 15.3 ms and 27.2±7.1 ms in ventricular fibrillation(VF)group (n=10),non-VF group(n=60)and healthy control group(n=20)respectively. QTcd was 36.3± 31.l ms and 39.5±22. 5ms in anterior(n=30)and inferior(n=40) myocardial infarction group respectively. Of the 25 patients with QTcd≥ 40 ms,9(36%)developed VF. Of the 29 cases with QTcd<40 ms and QTc<440 ms,none developed VF. The results suggested that increased QTcd in the elderly after AMI was related to VF.