Vevo Apps Talk

This month Kristiina explains Left Lateral Decubitus Position:

Although you would originally assume that echocardiography would be easier in rat than in mouse, anyone who has done both will quickly acknowledge that the former is actually more challenging. Despite the larger size of the rat heart, ultrasound scanning is more difficult due to increased skin thickness, increased lung artifact and the increased shifting of lung and heart within the thorax. These challenges are typically worsened for larger rats.

To ensure you continue to achieve reliable, great images you can try modifying the position of your rat on the platform to a left lateral decubitus position. This involves lifting the right front and hind paws and turning the rat so it is lying on its left side. This will cause the left lung to drop and will minimize the lung shadow that appears over the heart. It will also cause the heart to shift closer to the anterior thoracic wall. You can then continue scanning the rat, approaching it with the same angle you would normally use (relative to the position of the rats’ thorax). This will require you to hand scan, as opposed to using the rail system. Although more technically challenging, this technique will assist you in achieving better cardiac scans in large rats.

To go a bit further, if you are still having difficulties, I find it helpful to use my left hand and put a bit of pressure on the animals’ back while I scan.

Still need ECG recordings? Once you remove the two paws from the platform you will no longer be receiving live ECG and respiration recordings. To mitigate this drawback we offer wired electrodes with our Vevo eBox. This allows you to continue to monitor live physiology without using the fixed electrodes on the heated handling platform.

This is a really nice technique I use all the time when scanning rats.