Myocardial stunning
Encyclopedia
Myocardial stunning is the reversible reduction of function of heart contraction
after reperfusion not accounted for by tissue damage or reduced blood flow.
After total ischemia occurs, the myocardium switches immediately form aerobic glycolysis to anaerobic glycolysis
resulting in the reduced ability to produce high energy phosphates such as ATP
and Creatinine Phosphate
. At this point, the lack of the energy and lactate
accumulation results in cessation of contraction within 60 seconds of ischemia
(i.e. Vessel Occlusion). Subsequent to this is a period of "myocardial stunning," in which reversible ischemic damage is taking place. At approximately 30 minutes after the onset of total ischemia the damage becomes irreversible, thereby ending the phase of myocardial stunning.
Heart Beat
Heart Beat is a 1980 film written and directed by John Byrum, based on the autobiography by Carolyn Cassady. The film is about seminal figures in the Beat Generation...
after reperfusion not accounted for by tissue damage or reduced blood flow.
After total ischemia occurs, the myocardium switches immediately form aerobic glycolysis to anaerobic glycolysis
Anaerobic glycolysis
Anaerobic glycolysis is the transformation of glucose to pyruvate when limited amounts of oxygen are available. Anaerobic glycolysis is only an effective means of energy production during short, intense exercise, providing energy for a period ranging from 10 seconds to 2 minutes...
resulting in the reduced ability to produce high energy phosphates such as ATP
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...
and Creatinine Phosphate
Creatinine
Creatinine is a break-down product of creatine phosphate in muscle, and is usually produced at a fairly constant rate by the body...
. At this point, the lack of the energy and lactate
Lactate
Lactate may refer to:*The act of lactation*The conjugate base of lactic acid...
accumulation results in cessation of contraction within 60 seconds of ischemia
Ischemia
In medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...
(i.e. Vessel Occlusion). Subsequent to this is a period of "myocardial stunning," in which reversible ischemic damage is taking place. At approximately 30 minutes after the onset of total ischemia the damage becomes irreversible, thereby ending the phase of myocardial stunning.