Obayashi T, Umezawa S, Chun Y H, Inada M, Korenaga M, Kanayama M, Taniguchi K
Department of Internal Medicine, Yokosuka Kyosai General Hospital.
J Cardiol. 1989 Mar;19(1):67-77.
To assess the relationships among wall motion abnormality, myocardial ischemia and ST change in patients with myocardial infarction (MI), dobutamine stress thallium (Tl) myocardial scintigraphy, and two-dimensional echocardiography (2DE) and electrocardiography were simultaneously performed. Sixteen patients with anterior MI who underwent 2DE and ECG were studied at baseline and during dobutamine infusion with incremental doses of two to 40 micrograms/kg/min. The stress endpoints were chest pain, significant ST changes, tachycardia (greater than or equal to 110/min), and complicated arrhythmias. At the maximal tolerable dose of dobutamine, Tl scintigraphy was completed, and then repeated again four hours later. Left ventricular wall motion was evaluated using superimposed wall tracings of the configuration on 2DE, and was expressed as regional % area changes. Myocardial ischemia was quantified by SPECT and measured as regional % Tl uptake. Dobutamine stress testing was well tolerated by all patients, and no complications occurred. Hemodynamic changes included: heart rate increased from 61 +/- 9 to 113 +/- 11 beats/min, left ventricular end-diastolic volume (2DE) decreased from 93 +/- 27 to 59 +/- 33 ml, and mean blood pressure and ejection fraction were unchanged. In 11 of the 16 patients, redistributions on planar and SPECT images were observed. Although redistributions were observed in the areas adjacent to infarcts in patients with significant ST elevation in V3, additional wall motion abnormalities were not observed. The shape of the ST elevation had no relation to myocardial ischemia. In some cases, wall motion abnormality can be improved in spite of ischemia. Thus, this new combined method is useful for evaluating the relationship between ischemia and wall motion dynamics.
为评估心肌梗死（MI）患者的室壁运动异常、心肌缺血与ST段改变之间的关系，同时进行了多巴酚丁胺负荷铊（Tl）心肌闪烁显像、二维超声心动图（2DE）和心电图检查。对16例接受2DE和心电图检查的前壁MI患者在基线状态以及多巴酚丁胺以2至40微克/千克/分钟递增剂量输注期间进行了研究。负荷终点为胸痛、显著的ST段改变、心动过速（大于或等于110次/分钟）和复杂性心律失常。在多巴酚丁胺的最大耐受剂量时，完成Tl闪烁显像，然后在4小时后再次重复。使用2DE上配置的叠加室壁描记评估左心室壁运动，并表示为局部面积变化百分比。通过单光子发射计算机断层扫描（SPECT）对心肌缺血进行定量，并测量为局部Tl摄取百分比。所有患者对多巴酚丁胺负荷试验耐受性良好，未发生并发症。血流动力学变化包括：心率从61±9次/分钟增加到113±11次/分钟，左心室舒张末期容积（2DE）从93±27毫升降至59±33毫升，平均血压和射血分数未改变。16例患者中有11例在平面和SPECT图像上观察到再分布。尽管在V3导联ST段显著抬高的患者梗死灶附近区域观察到再分布，但未观察到额外的室壁运动异常。ST段抬高的形态与心肌缺血无关。在某些情况下，尽管存在缺血，室壁运动异常仍可改善。因此，这种新的联合方法有助于评估缺血与室壁运动动力学之间的关系。
