Gallagher K P, Kumada T, Battler A, Kemper W S, Ross J
Am J Physiol. 1982 Feb;242(2):H260-7. doi: 10.1152/ajpheart.1982.242.2.H260.
Stress-induced regional myocardial ischemia in the presence of mild coronary stenosis was studied in five dogs 2-4 wk after implantation of pairs of ultrasonic crystals to measure left ventricular wall thickening (% delta WT) and subendocardial segmental shortening (% delta L). Isoproterenol (0.2 micrograms.kg-1.min-1) was infused before and after production of coronary stenosis, which produced no resting dysfunction. During isoproterenol infusion with coronary stenosis % delta WT and subendocardial % delta L were significantly decreased although blood flow was comparable to conditions at rest, indicating that the demand for blood flow exceeded supply. Linear regression analysis of mean transmural blood flow versus % delta WT during isoproterenol demonstrated that wall thickening was significantly related to changes in mean blood flow: y (percentage wall thickening) = 27.5 X (transmural blood flow) -8.2 (r = 0.83); likewise % delta L was significantly related to subendocardial blood flow during isoproterenol infusion: y (percentage shortening) = 17.1 X (subendocardial blood flow) -0.4 (r = 0.85). These results indicate that both regional % delta WT and % delta L sensitively reflect the adequacy of myocardial perfusion even during stress-induced changes in myocardial O2 demands and blood flow.
在五只犬植入成对超声晶体以测量左心室壁增厚（%ΔWT）和心内膜下节段缩短（%ΔL）2 - 4周后，研究了在轻度冠状动脉狭窄情况下应激诱导的局部心肌缺血。在冠状动脉狭窄形成前后输注异丙肾上腺素（0.2微克·千克⁻¹·分钟⁻¹），冠状动脉狭窄形成后未产生静息功能障碍。在冠状动脉狭窄情况下输注异丙肾上腺素期间，尽管血流与静息状态相当，但%ΔWT和心内膜下%ΔL显著降低，这表明血流需求超过了供应。异丙肾上腺素输注期间平均透壁血流与%ΔWT的线性回归分析表明，壁增厚与平均血流变化显著相关：y（壁增厚百分比）= 27.5X（透壁血流） - 8.2（r = 0.83）；同样，在异丙肾上腺素输注期间%ΔL与心内膜下血流显著相关：y（缩短百分比）= 17.1X（心内膜下血流） - 0.4（r = 0.85）。这些结果表明，即使在应激诱导心肌氧需求和血流变化期间，局部%ΔWT和%ΔL均能敏感地反映心肌灌注是否充足。
