INPUT IMPEDANCE OF SYSTEMIC CIRCULATION IN MAN
INPUT IMPEDANCE OF SYSTEMIC CIRCULATION IN MAN
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DOI：
10.1161/01.res.40.5.451
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发表时间：
1977-01-01
影响因子：
20.1
通讯作者：
MILNOR, WR
中科院分区：
文献类型：
--
作者：
NICHOLS, WW;CONTI, CR;MILNOR, WR
为了确定系统输入阻抗，我们测量了16例接受诊断性心导管插入术的人升主动脉的脉动压力和流量。用导管尖端的电磁测速仪测量血流，用与导管充液腔相连的外部换能器测量压力。5名受试者无心血管疾病（A组，平均年龄32岁+-）。2年，平均主动脉压97±。4mmhg)。7例有冠状动脉疾病的临床和血管造影征象，平均血压小于100mmhg （B组，平均年龄48岁）。2年)。4名受试者有冠心病征象，平均血压大于100 mm Hg （C组，平均年龄48岁+-）。3年)。三组阻抗频谱定性相似，与先前在狗主动脉中观察到的阻抗频谱相似。正常人（A组，平均53 dyn s cm-5）的特征阻抗低于冠心病患者（B组和C组，平均129 dyn s cm-5）。在冠心病患者中，高血压患者（C组，平均202 dyn s cm-5）的特征阻抗高于平均血压较低的患者（B组，平均95 dyn s cm-5）。单位时间左心室外功（水力功率）A组平均为1715 mW， B组为1120 mW， C组为2372 mW。所有受试者的心输出量均在正常范围内，但B组倾向于低于C组。C组受试者显然能够更好地满足异常高的主动脉输入阻抗所增加的能量需求。冠状动脉疾病患者的高阻抗是否仅随年龄和跨壁压力的增加而增加，或者是否涉及其他因素，需要进一步的研究。相对正常受试者的数据允许对人类主动脉输入阻抗正常限度的暂定定义：26-80 dyn / cm-5。
To determine the systemic input impedance, pulsatile pressure and flow were measured in the ascending aorta in 16 human subjects who were undergoing diagnostic cardiac catheterization. Blood flow was measured with a catheter-tip electromagnetic velocity meter, and pressure with an external transducer connected with the fluid-filled lumen of the catheter. Five subjects were found to have no evidence of cardiovascular disease (group A, mean age 32 .+-. 2 yr, mean aortic pressure 97 .+-. 4 mm Hg). Seven had clinical and angiographic signs of coronary arterial disease, and mean pressures less than 100 mm Hg (group B, mean age 48 .+-. 2 yr). Four subjects had signs of coronary disease and mean pressures greater than 100 mm Hg (group C, mean age 48 .+-. 3 yr). The frequency spectra of impedance were qualitatively similar in all 3 groups and resembled those previously observed in the dog aorta. Characteristic impedance was lower in the normal subjects (group A, average 53 dyn s cm-5) than in the subjects with coronary artery disease (groups B and C, average 129 dyn s cm-5). Among the subjects with coronary disease, characteristic impedance was higher in the hypertensive subjects (group C, average 202 dyn s cm-5) than in those with lower mean pressures (group B, average 95 dyn s cm-5). External left ventricular work per unit time (hydraulic power) averaged 1715 mW in group A, 1120 mW in group B, and 2372 mW in group C. Cardiac outputs were within normal limits in all subjects, but tended to be lower in group B than in group C. The subjects of group C were apparently better able to meet the increased energy demands imposed by an abnormally high aortic input impedance. Further investigation is needed to learn whether the high impedances in subjects with coronary disease represent an increase with age and transmural pressure alone, or whether some additional factor is involved. The data on relatively normal subjects permit a tentative definition of the normal limits for aortic input impedance in man: 26-80 dyn s cm-5.