RT Journal
A1 HECHT HH
T1 COncepts of myocardial ischemia
JF Archives of Internal Medicine
JO Archives of Internal Medicine
YR 1949
FD November 1
VO 84
IS 5
SP 711
OP 729
DO 10.1001/archinte.1949.00230050047002
UL http://dx.doi.org/10.1001/archinte.1949.00230050047002
AB MYOCARDIAL ischemia occurs whenever there exists a discrepancy between the available oxygen supply and the work requirements of the heart muscle. The balance of these two factors is essential for cardiac function. An arterial blood flow below that customarily available for work performance results in myocardial ischemia.As shown in table 1, a decrease in oxygen supply to the heart muscle may be absolute, owing to narrowing of arterial caliber by occlusive disease, prolonged spasm or a decrease in the oxygen-carrying capacity of the blood (anemia). The decrease may be relative when the arterial supply provided for the normal heart must serve a greater muscular mass than normal (as in cardiac hypertrophy) or when the energy requirements exceed the maximal capacity of the coronary bed. It is also possible that the utilization of available oxygen is impaired either because oxygen is offered to the tissues in nonutilizable form (as in