Biomaterial Database

The importance of myocardial perfusion in the pathogenesis of the cardiac pathology associated with +Gz exposure in miniature swine. 1980

M H Laughlin, and J T Young, and W M Witt, and P P Crump

Minor cardiomyopathy has been associated with exposure of miniature swine to levels of high sustained +Gz which can be attained routinely in new USAF high-performance aircraft. One possible cause of these lesions is total or regional myocardial ischemia. To test this hypothesis, regional coronary blood flow was measured with the radiolabeled microsphere technique in chronically instrumented miniature swine during 60-s exposures to +3Gz, +5Gz, or +7Gz. Acceleration exposure resulted in detectable left ventricular subendocardial hemorrhage in 1 of 5 animals exposed to +3Gz, in 7 of 8 animals exposed to +5Gz and in all 8 animals exposed to +7Gz. All levels of +Gz stress caused 2-3 fold increases in coronary blood flow. The regional distribution of coronary blood flow during +Gz was similar to that under resting control conditions as long as aortic diastolic pressure was maintained. There was no clear evidence of total or regional myocardial ischemia during +Gz or of any relationship between regional coronary blood flow and the presence of subendocardial hemorrhage. It is concluded that myocardial ischemia is not a primary factor in the pathogenesis of the cardiac lesions associated with the exposure of miniature swine to +Gz stress.

UI	MeSH Term	Description	Entries
D008863	Microspheres	Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.	Latex Beads,Latex Particles,Latex Spheres,Microbeads,Bead, Latex,Beads, Latex,Latex Bead,Latex Particle,Latex Sphere,Microbead,Microsphere,Particle, Latex,Particles, Latex,Sphere, Latex,Spheres, Latex
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009202	Cardiomyopathies	A group of diseases in which the dominant feature is the involvement of the CARDIAC MUSCLE itself. Cardiomyopathies are classified according to their predominant pathophysiological features (DILATED CARDIOMYOPATHY; HYPERTROPHIC CARDIOMYOPATHY; RESTRICTIVE CARDIOMYOPATHY) or their etiological/pathological factors (CARDIOMYOPATHY, ALCOHOLIC; ENDOCARDIAL FIBROELASTOSIS).	Myocardial Disease,Myocardial Diseases,Myocardial Diseases, Primary,Myocardial Diseases, Secondary,Myocardiopathies,Primary Myocardial Disease,Cardiomyopathies, Primary,Cardiomyopathies, Secondary,Primary Myocardial Diseases,Secondary Myocardial Diseases,Cardiomyopathy,Cardiomyopathy, Primary,Cardiomyopathy, Secondary,Disease, Myocardial,Disease, Primary Myocardial,Disease, Secondary Myocardial,Diseases, Myocardial,Diseases, Primary Myocardial,Diseases, Secondary Myocardial,Myocardial Disease, Primary,Myocardial Disease, Secondary,Myocardiopathy,Primary Cardiomyopathies,Primary Cardiomyopathy,Secondary Cardiomyopathies,Secondary Cardiomyopathy,Secondary Myocardial Disease
D003326	Coronary Circulation	The circulation of blood through the CORONARY VESSELS of the HEART.	Circulation, Coronary
D003327	Coronary Disease	An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.	Coronary Heart Disease,Coronary Diseases,Coronary Heart Diseases,Disease, Coronary,Disease, Coronary Heart,Diseases, Coronary,Diseases, Coronary Heart,Heart Disease, Coronary,Heart Diseases, Coronary
D005260	Female		Females
D006112	Gravitation	Acceleration produced by the mutual attraction of two masses, and of magnitude inversely proportional to the square of the distance between the two centers of mass. It is also the force imparted by the earth, moon, or a planet to an object near its surface. (From NASA Thesaurus, 1988)	G Force,Gravistimulation,Gravity,Force, G,G Forces,Gravities
D006439	Hemodynamics	The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.	Hemodynamic
D006470	Hemorrhage	Bleeding or escape of blood from a vessel.	Bleeding,Hemorrhages
D000054	Acceleration	An increase in the rate of speed.	Accelerations