Evaluation of cardiac function and myocardial perfusion in small animals: Capability of echocardiography

Abstract

Background Recently, there have been many studies on genes or regenerations using small animals such as mice and rats. However, the therapeutic effects in genes or cell levels were not always available in organs. The effects on organs were evaluated by pathologic examinations. Ultrasound, a noninvasive examination, was used to evaluate organs of small animals. However, it was very difficult to evaluate in detail because of limited resolution. The evaluation of hearts in small animals is very difficult due to rapid heart rate and small size. Purpose We would like to introduce the availability of echocardiography to evaluate the cardiac function and myocardial perfusion in small animals. Methods Fourteen open-chest rats were examined to evaluate myocardial perfusion. Intravenous myocardial contrast echocardiography (MCE) was performed by fundamental and intermittent mode using a high-frequency transducer with SONOS 5500 during injection of NC 1001000. We compared the area at risk by MCE with that by Evans blue staining. Result All wall segments were clearly opacified and the risk area was clearly observed in the cases where the left anterior descending coronary artery was ligated. There was a good correlation between the area at risk by MCE and that by Evans blue staining. Conclusion Intravenous myocardial contrast echocardiography can detect perfusion defects, even in rats, using a high-frequency transducer.