Which term describes a mechanical device that assists the heart rather than replacing it?

A right ventricular assist device (RVAD) is specifically designed to support the function of the heart, particularly the right ventricle, without completely replacing it. This device is typically used in patients with severe heart failure to enhance blood flow and alleviate symptoms while allowing the heart to rest and potentially recover. The RVAD assists the natural pumping action of the heart, improving blood circulation and oxygen delivery to the body's organs and tissues.

In contrast, a heart-lung machine is utilized during surgeries to take over the work of both the heart and lungs, which is a more comprehensive replacement rather than assistance. An automatic external defibrillator (AED) is a device designed to restore normal heart rhythms in cases of cardiac arrest, but it does not assist in pumping blood. A cardiac monitor is used to observe and display the electrical activity of the heart but does not provide any mechanical support. Thus, the right ventricular assist device is the most suitable option for describing a device that helps the heart rather than replacing it.