Increased protection of the ischemic myocardium by decreased aortic pressure.
The elevation of aortic pressure increases myocardial oxygen consumption and increases the blood supply to the myocardium. It is not obvious whether elevated systemic arterial pressure would enhance or diminish myocardial protection during acute myocardial ischemia. This report reviews previously published data on the effects of aortic pressure elevation on the coronary pressure-flow relationship, and on the ischemic myocardium in the dog. The shift of the maximally-dilated coronary pressure-flow line to the right on the pressure-flow diagram is an indication of the deterioration of the oxygen supply/demand ratio caused by aortic pressure elevation. The only maneuver recognized for protecting the ischemic myocardium is early reperfusion. In patients with de novo acute myocardial ischemia, we propose that myocardial protection can be enhanced by reduction of systemic blood pressure until coronary reperfusion therapy is initiated.
Nakamura
Y
Y
Department of Geriatrics, Keio University School of Medicine, Tokyo, Japan.
Iwanaga
S
S
Uno
K
K
D000818:Animals; D001011:Aorta / Q000503:physiopathology*; D001794:Blood Pressure; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology; D004285:Dogs; D017202:Myocardial Ischemia / Q000503:physiopathology*; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption