[Effect of oxygen inhalation on myocardial opacification using levovist: an animal experimental study].
OBJECTIVE
Levovist can opacify the myocardium via venous injection, and is widely used in the clinical field. However, left ventricular opacification deteriorates during oxygen inhalation using Albunex, one of the first generation of contrast agents. This study examines the effect of blood oxygen pressure on the myocardial opacification by Levovist.


METHODS
Myocardial contrast echocardiography (Toshiba Power Vision 6000) was performed using second harmonic imaging, intermittent exposure of ultrasound (every 4 cardiac beats) and acoustic power of 1.4 mechanical index. The video intensity of the ventricular septum after venous injection of Levovist (0.5 ml of 300 mg/ml) was measured under various respiratory conditions by manipulating the respirator and oxygen inhalation. Arterial blood gas was measured and correlated with the myocardial video intensity.


RESULTS
The video intensity of myocardial opacification was lower with higher oxygen pressure in the arterial blood. Visual recognition of myocardial opacification was only 14% under high oxygen pressure over 200 mmHg. Microbubbles of Levovist form from normal air, and are easily affected by the gas concentration of the surrounding blood.


CONCLUSIONS
Myocardial opacification using Levovist is deteriorated under high oxygen pressure at examination.
Kashiwagi
Y
Y
School of Allied Health Sciences, Osaka University, Faculty of Medicine, Yamadaoka 1-7, Suita, Osaka 565-0871.
Beppu
S
S
Ishikura
F
F
Ueda
H
H
Yagura
S
S
Kayano
H
H
D000280:Administration, Inhalation; D000818:Animals; D003287:Contrast Media; D003326:Coronary Circulation; D004285:Dogs; D004452:Echocardiography; D007089:Image Enhancement; D008297:Male; D010100:Oxygen / Q000008:administration & dosage* / Q000097:blood; D010313:Partial Pressure; D011134:Polysaccharides
D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508; D010100:Oxygen