AJP - Heart and Circulatory Physiology, Vol 244, Issue 3 429-H436, Copyright © 1983 by American Physiological Society
Ventricular filling pressure as a determinant of coronary blood flow during ischemia
R. B. Dunn and D. M. Griggs Jr
The role of ventricular filling pressure (VFP) as a determinant of coronary
blood flow (CBF) in the acutely ischemic ventricle was examined in the
open-chest dog under conditions of a reduced, constant coronary artery
pressure and an unstable VFP. Blood delivery to different layers of the
ventricle and ischemic metabolic changes occurring in these layers were
also determined and compared with appropriate control data. A close,
inverse, linear relationship between VFP and CBF was found in animals
exhibiting a progressive rise in VFP from 6 +/- 0 to 25 +/- 1 mmHg (r =
0.99). A lower endocardial-to-epicardial ratio of delivered blood and a
steeper transmural gradient in ischemic metabolic changes were noted in
these animals compared with similarly prepared animals exhibiting a stable
VFP. The findings demonstrate the importance of VFP as a determinant of CBF
during ischemia, and they lend support to the concept that blood flow in
the ischemic ventricle is regulated by a preload-dependent transmural
gradient in coronary driving pressure.
