QT dispersion is determined by the extent of viable myocardium in patients with chronic Q-wave myocardial infarction.
QT dispersion is determined by the extent of viable myocardium in patients with chronic Q-wave myocardial infarction.
复制标题
QT 离散度由慢性 Q 波心肌梗塞患者的存活心肌范围决定。
作者：
C. Schneider;E. Voth;F. Baer;M. Horst;R. Wagner;U. Sechtem
背景
急性心肌梗死后溶栓成功的患者QT离散度较低，提示QT离散度可能由存活心肌和瘢痕心肌的程度决定。
方法和结果
为了验证这一假设，在44例慢性Q波心肌梗死患者的12导联静息心电图中测量了QT离散度。为了评估存活心肌和瘢痕心肌的程度，所有患者均接受了F-18氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）。此外，所有患者均接受了梗死相关动脉的血运重建，并在4个月后重复血管造影。PET显示梗死区有大量存活心肌的患者（平均FDG摄取>或=标准化最大FDG摄取的50%）的QT离散度较低（53+/-20vs94 +/-24ms，P<0.0001），而仅有少量存活心肌的患者的QT离散度较低。梗死区FDG平均摄取量和FDG缺损面积与QT离散度显著相关（r= 0.64，P<0.0001; r= 0.67，P<0.0001），而射血分数与此无关（r<0.1，P=NS）。QT离散度≤ 70 ms预测梗死区存活心肌的敏感性为85%，特异性为82%。在血运重建后4个月左心室功能改善的患者中，QT离散度也较低（54+/-21 vs 88+/-30 ms，P=.0003）。QT离散度≤ 70 ms预测左室功能改善的敏感性为83%，特异性为71%。
结论
QT离散度是由梗死区存活心肌的数量决定的，可以作为慢性Q波心肌梗死患者梗死区实质存活能力的一种新的、快速可用的标记物。
BACKGROUND
QT dispersion is lower in patients with successful thrombolysis after acute myocardial infarction, suggesting that QT dispersion may be determined by the extent of viable and scarred myocardium.
METHODS AND RESULTS
To test this hypothesis, QT dispersion was measured in a 12-lead resting ECG in 44 patients with chronic Q-wave myocardial infarction. To assess the extent of viable and scarred myocardium, all patients underwent F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET). In addition, all patients had revascularization of the infarct-related artery and repeated angiography 4 months later. QT dispersion was lower (53+/-20 versus 94+/-24 ms, P<.0001) in patients with evidence of a substantial amount of viable myocardium in the infarct region as demonstrated by PET (average FDG uptake > or = 50% of normalized, maximum FDG uptake) than in patients with only minimal residual viability. Average FDG uptake of the infarct region and FDG defect size were significantly related to QT dispersion (r=.64, P<.0001; r=.67, P<.0001), whereas ejection fraction was not (r<.1, P=NS). QT dispersion of < or = 70 ms had a sensitivity of 85% and a specificity of 82% to predict viable myocardium in the infarct region. QT dispersion was also lower in patients with improvement of left ventricular function 4 months after revascularization (54+/-21 versus 88+/-30 ms, P=.0003). QT dispersion of < or = 70 ms had a sensitivity of 83% and a specificity of 71% to predict improvement of left ventricular function.
CONCLUSIONS
QT dispersion is determined by the amount of viable myocardium in the infarct region and may serve as a novel, rapidly available marker of substantial viability in the infarct region of patients with chronic Q-wave myocardial infarction.
慢性心电图 Q 波梗塞患者的区域灌注、葡萄糖代谢和室壁运动：通过正电子发射断层扫描证明某些梗塞区域存活组织持续存在的证据。
影响因子：
37.8
作者：
Brunken,R;Tillisch,J;Schwaiger,M;Child,JS;Marshall,R;Mandelkern,M;Phelps,ME;Schelbert,HR
通讯作者：
Schelbert,HR