村上 陽, 松野 好男, 小林 茂雄, 盛岡 茂文, 森山 勝利

Yo MURAKAMI, Yoshio MATSUNO, Shigeo KOBAYASHI, Shigefumi MORIOKA, Katsutoshi MORIYAMA

島根医科大学第四内科

The Fourth Department of Internal Medicine, Shimane Medical University

キーワード : Velocity-stress relation, Stress-dimension relation, Cardiac hypertrophy, Unanesthetized dogs, Systemic hypertension

We have previously observed "parallel leftward shift" of the end-systolic wall stress-dimension (WSes-Des) relationship in the hypertrophied left ventricle (LVH) induced by the perinephritic hypertension (PNH). However, the significance of this leftward shift of the WSes-Des relationship for the inotropic state of the hypertensive ventricle remained unknown. The purpose of this study is to evaluate the significance of the "parallel leftward shift" of the WSes-Des relationship in LVH. We used 11 mongrel dogs (6 were sham-operation controls, 5 had PNH) and measured the other index of the inotropic state, the relationship of the mean velocity of circumferential fiber shortening to end-systolic wall stress (mVcf-WSes), before and at the eighth week of PNH. The WSes-Des and the mVcf-WSes relationship were generated by the intravenous administration of nitroglycerin to the unanesthetized dogs. Left ventricular wall thickness, the left ventricular internal dimensions and central aortic pressure were simultaneously recorded with echocardiography and a catheter-tipped micromanometer. The mean aortic pressure was increased significantly from 97±9 mmHg to 138± 22 mmHg in PNH (mean±S.D., p