CORONARY CIRCULATION IN MYOCARDIAL ISCHEMIA

Project: Research project

Description

Following acute coronary occulsion, the coronary collateral circulation becomes
the primary determinant of the extent of ischemia within the involved
myocardium. Accordingly, the overall objective of the proposed research is to
obtain a more complete understanding of the functional properties of the
coronary collateral circulation and its development. Experiments will be
carried out on the coronary circulation in dogs, pigs, rats, and in some cases,
functional and anatomical measurements will be conducted in human hearts
obtained at autopsy. Recent studies from this laboratory have shown that the
coronary circulation acts as a functional end artery circulation in which the
significant collateral vessels are inter-arterial anastomoses. Based on this
view, a detailed model of the coronary collateral circulation is proposed and
the experiments are designed to test the properties of the individual elements
of this model. A wide variety of physiological measurements including
myocardial blood flow with radioactive microsphere, retrograde coronary blood
flow and pressures will be made in animals prepared for acute study under highly
controlled conditions and in animals prepared with implanted occluders for study
under chronic conditions. Anatomical studies will be carried out in parallel,
including injection studies of the coronary and coronary collateral circulations
and histological examination of the developing collateral circulation. Specific
attention will be directed at the relationship between the distribution of the
collateral circulation and the histological evidence of necrosis. It is hoped
that a model will be developed which can confidently predict changes in
collateral function based on only measurements that can be obtained in infarct
patients. It will then be possible to evaluate clinical feasibility of
interventions designed to protect ischemic myocardium and minimize infarct size
in terms of the effect on coronary collateral blood flow.
StatusFinished
Effective start/end date6/30/7812/31/87

Funding

  • National Institutes of Health
  • National Institutes of Health

Fingerprint

Coronary Circulation
Collateral Circulation
Myocardial Ischemia
Microspheres
Autopsy
Myocardium
Necrosis
Swine
Ischemia
Arteries
Dogs
Pressure
Injections
Research

ASJC

  • Medicine(all)