Ultrasound energy improves myocardial perfusion in the presence of coronary occlusion

Objectives We evaluated whether ultrasound improves myocardial tissue perfusion in 14 animals with coronary artery occlusion. Background 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. Methods 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). Results The TPU decreased from 100.9 ± 13 at baseline to 71.1 ± 13 (p Conclusions Low-frequency, low-intensity ultrasound improves myocardial tissue perfusion and pH in the presence of a fixed coronary artery occlusion.