Effect of the positioning of a balloon valve in the aorta on coronary flow during aortic regurgitation.
The coronary artery flow changes relative to the function of a catheter-mounted balloon valve used for relief of aortic regurgitation were studied in 10 mongrel dogs. Acute aortic regurgitation was produced by severing the aortic cusps with a long needle. Coronary flow was recorded from the left anterior descending coronary artery through an electromagnetic flowmeter. When the balloon was functioning within the cavity of the left ventricle there were no significant changes in the coronary flow and aortic pressure, except for a slight decrease in the aortic end-diastolic pressure. When it was functioning in the aortic ring the coronary flow increased 6.52 +/- 1.65 ml/min/100 gm of myocardium (p less than 0.001) and became predominantly diastolic. When it was functioning in the ascending aorta the coronary flow decreased 6.22 +/- 1.16 ml/min/100 gm of myocardium (p less than 0.001) and remained predominantly systolic. Finally, when the balloon was functioning in the thoracic aorta the coronary flow did not change significantly. With the balloon functioning in the aortic ring, ascending aorta, or thoracic aorta, there was a significant increase in the aortic end-diastolic pressure and decrease in the pulse pressure distal to the location of the balloon. It is concluded that the location of the balloon valve inserted for relief of aortic regurgitation influences the effect on coronary arterial flow.
D000818:Animals; D001011:Aorta; D001013:Aorta, Thoracic; D001022:Aortic Valve Insufficiency / Q000503:physiopathology / Q000628:therapy*; D001243:Assisted Circulation / Q000379:methods*; D001783:Blood Flow Velocity; D001794:Blood Pressure; D006328:Cardiac Catheterization; D003326:Coronary Circulation; D004285:Dogs; D055590:Electromagnetic Phenomena; D006801:Humans; D011446:Prospective Studies