The sequential changes of the corrected QT dispersion (QTcD) were studied in 136 patients 1 day to 30 days after a transmural acute myocardial infarction (AMI) to investigate the optimal measurement time of QT dispersion for risk stratification. The study group included 136 patients (89 men; mean age, 57 ±10 years) with transmural AMI who were treated with throm bolytics (Tr+ group, n = 73) or not (Tr- group, n = 63) and 65 healthy controls (43 men; mean age, 56 ±7 years). Fourteen patients in whom ventricular tachycardia (VT), ventricular fibrilla tion (VF), or sudden cardiac death developed during the 30-day period were also evaluated as major cardiac arrhythmia (MCA) group. ECGs were obtained for each patient on days 1, 3, 5, 10, 15, and 30 after AMI. QTc dispersion in patients with AMI (for every period of QTcD after MI) was significantly more prolonged than in normal controls (49.3 ± 16.3 ms) (p < 0.001). QTcD was significantly greater in patients without thrombolytics than in patients with thrombolytics for every period (days 1, 3, 5, 10, 15, and 30) of QTcD after MI (p < 0.001). The mean of QTcD was significantly greater in patients with MCA than in patients without MCA group for every period (days 1, 3, 5, 10, 15, and 30) of QTcD after MI (p < 0.05). Maximal QTcD was seen on day 10 (p < 0.05 1st vs day 10 for each group) after myocardial infarction, and then reached a plateau for an each group. The ideal time to measure the QTD for risk stratification is at least 10 days after AMI.
研究了136例透壁性急性心肌梗死(AMI)患者在接受溶栓治疗(Tr+组,n = 73)或不接受溶栓治疗(Tr-组,n = 63)后1天至30天内校正QT离散度(QTcD)的序贯变化,以探讨QT离散度测量时间对风险分层的最佳时间。研究组包括136例透壁性AMI患者(89名男性;平均年龄,57 ±10岁)和65名健康对照者(43名男性;平均年龄,56 ±7岁)。在30天内发生室性心动过速(VT)、心室颤动(VF)或心脏猝死的14例患者也被评估为重大心律失常(MCA)组。AMI后1、3、5、10、15和30天分别获得每位患者的ECG。AMI患者QTcD(MI后每个QTcD期间)较正常对照组明显延长(49.3 ± 16.3 ms)(p < 0.001)。MI后每个时期(1、3、5、10、15和30天)未接受溶栓治疗的患者QTcD显著高于接受溶栓治疗的患者(p < 0.001)。QTcD平均值在MCA组患者中较非MCA组患者每个时期(1、3、5、10、15和30天)显著升高(p < 0.05)。心肌梗死后第10天QTcD最大(p < 0.05,第1天与第10天各组比较),之后达到平台期。AMI后至少10天是测量QTD进行风险分层的理想时间。