TY - JOUR
T1 - Ultrasound energy improves myocardial perfusion in the presence of coronary occlusion
AU - Siegel, Robert J.
AU - Suchkova, Valentina N.
AU - Miyamoto, Takashi
AU - Luo, Huai
AU - Baggs, Raymond B.
AU - Neuman, Yoram
AU - Horzewski, Michael
AU - Suorsa, Veijo
AU - Kobal, Sergio
AU - Thompson, Todd
AU - Echt, Debra
AU - Francis, Charles W.
N1 - Funding Information:
This study has been supported by Timi3 Systems Inc. (Santa Clara, California), of which Dr. Siegel is a consultant and stockholder.
PY - 2004/10/6
Y1 - 2004/10/6
N2 - We evaluated whether ultrasound improves myocardial tissue perfusion in 14 animals with coronary artery occlusion. A recent study demonstrated that low-frequency ultrasound improves tissue perfusion in the rabbit ischemic limb, but there are no data on ultrasound enhancement of myocardial perfusion. Fourteen animals (9 dogs, 5 pigs) underwent thoracotomy and occlusion of a diagonal branch of the left anterior descending coronary artery. Myocardial tissue perfusion units (TPUs) and pH were measured before coronary occlusion, after occlusion, and after direct exposure of the ischemic myocardium in thepresence of fixed occlusion to low-frequency ultrasound (27 kHz). The TPU decreased from 100.9 ± 13 at baseline to 71.1 ± 13 (p < 0.01) after 60 min occlusion but rose by 19.7% to 85.1 ± 8 (p < 0.01) after ultrasound exposure for 60 min. After 60-min coronary occlusion, myocardial pH fell from 7.43 ± 14 to 7.05 ± 0.15 (p < 0.01) but then improved to normal (7.46 ± 0.32) after ultrasound for 60 min. Administration of l-Nω-nitro-arginine methyl esther (l-NAME), an inhibitor of nitric oxide synthase, before ultrasound exposure, blocked improvement in myocardial tissue perfusion and pH by ultrasound. Quantitative histomorphology showed a significant increase in the capillary area of myocardium exposed to ultrasound versus non-exposed myocardium (16.2 ± 7.9 vs. 8.2 ± 2.1, p < 0.02). Low-frequency, low-intensity ultrasound improves myocardial tissue perfusion and pH in the presence of a fixed coronary artery occlusion.
AB - We evaluated whether ultrasound improves myocardial tissue perfusion in 14 animals with coronary artery occlusion. A recent study demonstrated that low-frequency ultrasound improves tissue perfusion in the rabbit ischemic limb, but there are no data on ultrasound enhancement of myocardial perfusion. Fourteen animals (9 dogs, 5 pigs) underwent thoracotomy and occlusion of a diagonal branch of the left anterior descending coronary artery. Myocardial tissue perfusion units (TPUs) and pH were measured before coronary occlusion, after occlusion, and after direct exposure of the ischemic myocardium in thepresence of fixed occlusion to low-frequency ultrasound (27 kHz). The TPU decreased from 100.9 ± 13 at baseline to 71.1 ± 13 (p < 0.01) after 60 min occlusion but rose by 19.7% to 85.1 ± 8 (p < 0.01) after ultrasound exposure for 60 min. After 60-min coronary occlusion, myocardial pH fell from 7.43 ± 14 to 7.05 ± 0.15 (p < 0.01) but then improved to normal (7.46 ± 0.32) after ultrasound for 60 min. Administration of l-Nω-nitro-arginine methyl esther (l-NAME), an inhibitor of nitric oxide synthase, before ultrasound exposure, blocked improvement in myocardial tissue perfusion and pH by ultrasound. Quantitative histomorphology showed a significant increase in the capillary area of myocardium exposed to ultrasound versus non-exposed myocardium (16.2 ± 7.9 vs. 8.2 ± 2.1, p < 0.02). Low-frequency, low-intensity ultrasound improves myocardial tissue perfusion and pH in the presence of a fixed coronary artery occlusion.
UR - http://www.scopus.com/inward/record.url?scp=4644225804&partnerID=8YFLogxK
U2 - 10.1016/j.jacc.2004.06.062
DO - 10.1016/j.jacc.2004.06.062
M3 - Article
C2 - 15464327
AN - SCOPUS:4644225804
SN - 0735-1097
VL - 44
SP - 1454
EP - 1458
JO - Journal of the American College of Cardiology
JF - Journal of the American College of Cardiology
IS - 7
ER -