Laskey W K, Reichek N, St John Sutton M, Untereker W J, Hirshfeld J W
J Am Coll Cardiol. 1984 Feb;3(2 Pt 1):291-300. doi: 10.1016/s0735-1097(84)80012-1.
The coupling of myocardial oxygen consumption (MVO2) with its determinants in left ventricular hypertrophy in human beings is poorly understood. Therefore, thermodilution-derived coronary blood flow, MVO2 and left ventricular wall stress, obtained from simultaneous left ventricular M-mode echogram and pressure, were compared in 32 patients with various degrees of left ventricular hypertrophy. Patients were studied at rest and after mechanical load alteration with nitroglycerin or phenylephrine. Decreases in MVO2 (-5.7 +/- 0.8 ml/min; p less than 0.001) and the time integral of meridional ejection stress or shortening load (-1,297 +/- 152 X 10(3) dynes X s/cm2; p less than 0.001) were observed after nitroglycerin administration while increases in MVO2 (+5.5 +/- 0.7 ml/min; p less than 0.001) and shortening load (+1,412 +/- 137 X 10(3) dynes X s/cm2; p less than 0.001) were noted after phenylephrine. An index relating the change in MVO2 to the corresponding change in shortening load (SL), % delta MVO2/% delta SL, was significantly different in patients without (Group 1) and with (Group 2) clinical left ventricular failure. Left ventricular mass was similar in both groups. The mean % delta MVO2/% delta SL with phenylephrine in Group 1 (79.6 +/- 9.6) was greater than the index for Group 2 (35.5 +/- 6.1; p less than 0.005). With nitroglycerin, Group 2 patients exhibited a greater reduction in % delta MVO2/% delta SL (110.5 +/- 17.8) than Group 1 (54.0 +/- 9.4; p less than 0.01). In conclusion, in patients with left ventricular hypertrophy and dysfunction there appears to be a state of diminished coronary flow response to load augmentation. However, load reduction in patients with clinical left ventricular failure results in a more balanced relation between oxygen uptake and ejection stress.
人们对人类左心室肥厚中心肌耗氧量（MVO2）与其决定因素之间的耦合关系了解甚少。因此，我们对32例不同程度左心室肥厚患者进行了研究，比较了通过热稀释法获得的冠状动脉血流量、MVO2以及从同步左心室M型超声心动图和压力得出的左心室壁应力。对患者在静息状态下以及使用硝酸甘油或去氧肾上腺素改变机械负荷后进行研究。给予硝酸甘油后，观察到MVO2降低（-5.7±0.8 ml/min；p<0.001）以及经向射血应力或缩短负荷的时间积分降低（-1,297±152×10(3)达因×秒/平方厘米；p<0.001），而给予去氧肾上腺素后，观察到MVO2升高（+5.5±0.7 ml/min；p<0.001）以及缩短负荷升高（+1,412±137×10(3)达因×秒/平方厘米；p<0.001）。在无临床左心室衰竭的患者（第1组）和有临床左心室衰竭的患者（第2组）中，将MVO2的变化与缩短负荷（SL）的相应变化相关联的指标，即%ΔMVO2/%ΔSL，存在显著差异。两组的左心室质量相似。第1组使用去氧肾上腺素时的平均%ΔMVO2/%ΔSL（79.6±9.6）大于第2组的指标（35.5±6.1；p<0.005）。使用硝酸甘油时，第2组患者的%ΔMVO2/%ΔSL降低幅度（110.5±17.8）大于第1组（54.0±9.4；p<0.01）。总之，在左心室肥厚和功能障碍的患者中，冠状动脉对负荷增加的血流反应似乎存在减弱状态。然而，临床左心室衰竭患者负荷降低会导致氧摄取与射血应力之间的关系更加平衡。
