[Efficacy of intravenous myocardial contrast echocardiography for assessment of perfusion area of the heart in mice]

Abstract

Background and objectives: Intravenous myocardial contrast echocardiography is used clinically, but use in small animals has not been evaluated. The conditions for myocardial opacification and the feasibility of myocardial contrast echocardiography were examined in mice.

Methods: Closed chest mice were examined. The left ventricular short-axis view at the mid papillary muscle level was recorded before and after NC100100 injection using a SONOS 5500 (PHILIPS). Real time and intermittent triggering (every 5 beats) myocardial contrast echocardiography was performed with a mechanical index of low (0.3), middle (0.7), and high (1.5). Open chest mice were examined after left anterior descending coronary artery ligation. Myocardial contrast echocardiography was performed using intermittent triggering imaging (every 5 beats) with high mechanical index (1.5). The ratio of the non-perfused area to the whole left ventricular wall area was compared with that of the non-stained area by Evans Blue.

Results: The left ventricular myocardium was opacified in any setting. Good opacification was acquired at middle mechanical index (0.7) in real time myocardial contrast echocardiography and at high mechanical index (1.5) in intermittent myocardial contrast echocardiography. The opacified and non-opacified myocardium were clearly identified in all mice with coronary ligation. The non-opacified area ratio showed a good correlation with the non-stained area ratio (y = 0.93x + 0.51, r = 0.94, p < 0.05).

Conclusions: Myocardial contrast echocardiography can be used to assess myocardial perfusion and determine the ischemic area accurately in situ in the mouse.