AJP - Heart and Circulatory Physiology, Vol 268, Issue 5 1781-H1787, Copyright © 1995 by American Physiological Society
Unaltered size of right ventricular infarct in dogs with right ventricular hypertrophy induced by pressure overload
S. Tsumoto, S. Kawashima and T. Iwasaki
First Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
We investigated whether right ventricular infarct size is increased in the
hypertrophied right ventricle. In dogs, we produced chronic pressure
overload-induced right ventricular hypertrophy (RVH) and acute pulmonary
stenosis (APS) with a similar right ventricular systolic pressure to RVH.
Then, in an open-chest model, right coronary artery occlusion for 4 h
followed by 1 h of reperfusion was performed in animals with RVH or APS or
in controls. Regional myocardial blood flow was measured with
nonradioactive colored microspheres. Compared with the control group,
regional myocardial oxygen consumption in the right ventricle was increased
in the APS but not in the RVH group. The risk area and collateral blood
flow were comparable in the three groups. However, the infarct size
relative to risk area was increased in the APS group (42.3 +/- 4.9%), but
that in the RVH group (21.1 +/- 4.4%) was not different from controls (26.1
+/- 4.2%). Thus right ventricular infarction in the heart with RVH was not
increased compared with the normal heart.
