Ho Y L, Lin L C, Yen R F, Wu C C, Chen M F, Huang P J
Department of Internal Medicine (Cardiology), National Taiwan University Hospital, Taipei.
Am J Cardiol. 1999 Jul 15;84(2):125-9. doi: 10.1016/s0002-9149(99)00220-9.
The clinical significance of stress-induced ST-segment elevation and T-wave pseudonormalization in infarct-related leads is still controversial. Therefore, we conducted the present study to assess this issue using simultaneous dobutamine stress echocardiography (DSE) and thallium-201 single-photon emission computed tomography. A total of 119 patients with Q-wave myocardial infarction were enrolled in this study. There were 58 patients with (group I) and 61 patients without (group II) dobutamine-induced ST-T changes. Left ventricular ejection fraction was 43 +/- 13% in group I and 49 +/- 14% in group II (p <0.05). The baseline, low-, and peak-dose global wall motion scores were similar between these 2 groups (26.2 +/- 6.1 vs 26.2 +/- 6.3 [p = NS]; 24.1 +/- 5.3 vs 23.5 +/- 5.7 [p = NS]; 26.4 +/- 5.7 vs 26.7 +/- 6.1 [p = NS]). The sensitivity, specificity, and accuracy of these ST-T changes for detecting residual myocardial viability and ischemia documented by DSE in all patients were 50%, 53%, and 51% (for viability), and 47%, 48%, and 47% (for ischemia), respectively. The sensitivity, specificity, and accuracy of these ST-T changes for detecting a reversible perfusion defect documented by thallium-201 single-photon emission computed tomography were 51%, 54%, and 52%, respectively. In conclusion, dobutamine-induced ST elevation and/or T-wave pseudonormalization is associated with poor resting left ventricular function. These ST-T changes are not associated with residual myocardial ischemia and viability in the infarct area. Therefore, these electrocardiographic changes alone cannot be reliably considered as distinctive markers in formulating the therapeutic strategy of coronary intervention.
梗死相关导联中应激诱导的ST段抬高和T波假性正常化的临床意义仍存在争议。因此，我们进行了本研究，采用同步多巴酚丁胺负荷超声心动图（DSE）和铊-201单光子发射计算机断层扫描来评估这一问题。本研究共纳入119例Q波心肌梗死患者。其中58例患者（I组）出现多巴酚丁胺诱导的ST-T改变，61例患者（II组）未出现。I组左心室射血分数为43±13%，II组为49±14%（p<0.05）。这两组之间的基线、低剂量和峰值剂量整体壁运动评分相似（26.2±6.1对26.2±6.3 [p=无显著差异]；24.1±5.3对23.5±5.7 [p=无显著差异]；26.4±5.7对26.7±6.1 [p=无显著差异]）。在所有患者中，这些ST-T改变用于检测DSE记录的残余心肌存活和缺血的敏感性、特异性和准确性分别为50%、53%和51%（用于存活），以及47%、48%和47%（用于缺血）。这些ST-T改变用于检测铊-201单光子发射计算机断层扫描记录的可逆灌注缺损的敏感性、特异性和准确性分别为51%、54%和52%。总之，多巴酚丁胺诱导的ST段抬高和/或T波假性正常化与静息时左心室功能不良有关。这些ST-T改变与梗死区域的残余心肌缺血和存活无关。因此，仅这些心电图改变不能可靠地被视为制定冠状动脉介入治疗策略的独特标志物。
