Matsumura M, Kyo S, Yokote Y, Omoto R
First Department of Surgery, Saitama Medical School.
J Cardiol. 1991;21(1):29-41.
To evaluate myocardial perfusion and function of the interventricular septum after coronary artery bypass surgery, 29 patients with internal mammary artery grafts (IMAG) were examined using handgrip exercise Doppler echocardiography. IMAG flow was measured by color flow Doppler. Septal excursion and percent thickening of the interventricular septum during systole were measured as indicators of regional left ventricular function by M-mode echocardiography. Myocardial perfusion was estimated by thallium-201 exercise myocardial scintigraphy using a treadmill. 1. At rest, there were no significant correlations between IMAG flow and septal excursion and percent thickening or myocardial perfusion. 2. After the isometric handgrip exercise test, IMAG flow increased 20.0 +/- 3.9% from at rest, and the percentage of change in IMAG flow correlated significantly with changes in septal excursion (r = 0.63) and percent thickening (r = 0.72). It was found that a response of bypass graft flow to exercise has a correlation with contractility of cardiac muscle. 3. The rate of increase in IMAG flow in patients with normal myocardial scintigraphic findings (31.8 +/- 6.2%) was higher than that in patients with ischemia (15.3 +/- 5.6%) or infarction (15.0 +/- 11.3%). 4. A greater increase of percent thickening was observed in patients with normal exercise myocardial scintigraphic findings. These results suggest that the responses of the bypass graft flow to handgrip exercise may reflect viability and contractility of cardiac muscles perfused by the graft. Thus, exercise Doppler echocardiography is useful for evaluating regional myocardial perfusion and function of the interventricular septum after coronary artery bypass surgery.
为评估冠状动脉搭桥术后室间隔的心肌灌注及功能，对29例行乳内动脉移植术（IMAG）的患者进行了握力运动多普勒超声心动图检查。通过彩色多普勒测量IMAG血流。采用M型超声心动图测量室间隔在收缩期的偏移及增厚百分比，作为局部左心室功能指标。使用跑步机通过铊-201运动心肌闪烁显像评估心肌灌注。1. 静息时，IMAG血流与室间隔偏移、增厚百分比或心肌灌注之间无显著相关性。2. 等长握力运动试验后，IMAG血流较静息时增加20.0±3.9%，IMAG血流变化百分比与室间隔偏移变化（r = 0.63）及增厚百分比变化（r = 0.72）显著相关。发现旁路移植血管血流对运动的反应与心肌收缩力相关。3. 心肌闪烁显像结果正常患者的IMAG血流增加率（31.8±6.2%）高于有心肌缺血（15.3±5.6%）或梗死（15.0±11.3%）的患者。4. 运动心肌闪烁显像结果正常的患者增厚百分比增加更明显。这些结果表明，旁路移植血管血流对握力运动的反应可能反映了由移植血管灌注的心肌的存活性和收缩力。因此，运动多普勒超声心动图有助于评估冠状动脉搭桥术后局部心肌灌注及室间隔功能。
