Echocardiography for Impella 5.5® with SmartAssist®
Michael Galvin, a clinical educator at Abiomed, discusses how to measure the position of the Impella 5.5® with SmartAssist® using echocardiography and how this differs from measuring the position of the Impella CP® with SmartAssist®. He explains that the Impella 5.5 with SmartAssist provides up to 5.5 L/min of flow, is larger in diameter than the Impella CP with SmartAssist, and has a larger motor. It does not have a pigtail and is designed to sit deeper in the left ventricle.
When using echocardiography to measure the position of the Impella 5.5 with SmartAssist, the distance from the aortic valve leaflets to the middle of the inlet area should be approximately 5 cm, rather than the 3.5 cm distance for the Impella CP with SmartAssist. In addition, the bend in the cannula of the Impella 5.5 with SmartAssist should be positioned at the level of the aortic valve, unlike the bend in the Impella CP with SmartAssist, which appears above the aortic valve and is therefore typically not seen on echo.
When properly positioned, the Impella 5.5 with SmartAssist is not only situated at the proper depth in the left ventricle (5 cm from aortic valve to middle of inlet), but its position is stable and it is not rocking or swinging. In addition, the inlet is free-floating, surrounded by blood, and not obstructed or caught in mitral valve structures or touching the walls of the ventricle. The bend of the cannula appears at the level of the aortic valve and the outlet is positioned well above the aortic valve and unobstructed.