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Ventricular assist devices (VAD) commonly refer to surgically implanted pumps that are intended to assist one or both ventricles of the heart. They are most often placed in patients with severe congestive heart failure. Devices include left ventricular assist devices (LVADs), right ventricular assist devices (RVADs), and biventricular assist devices. The most common is the LVAD, with a cannula placed in the apex of the left ventricle, blood flow to the pump, and flow back through a cannula into the ascending aorta. Thus, the device assists the ventricle in moving blood through the circulatory system [3].

VADs were first developed in the 1960s. Technological advances made them more portable, but the patient was still confined to the hospital. In the 1990s, fully portable devices were developed that allowed VAD patients to be discharged from the hospital [11, 12]. VADs are most commonly used as a bridge to cardiac transplantation, but they also may be used as a bridge during a reversible cardiac condition or as a permanent destination therapy. There are two types of VAD patients. There are those with nonportable devices who require critical care transport with a perfusionist. Alternatively, those with portable VADs may be living at home where prehospital EMS clinicians may be called.

Currently, there are four generations of VADs with features that vary (Box 11.1). First‐generation devices mimic the pumping action of the left ventricle via the use of diaphragms or pusher plates that cause blood to be sucked into the left ventricle and expelled into the aorta. This mechanism results in pulsatile blood flow. The patient will have a pulse and blood pressure that can be measured [12]. The pumps are powered by electricity and can be either electromechanical or pneumatic. Electromechanical pumps use an electromagnetic pusher plate to drive the blood, whereas pneumatic devices use air pressure to move the blood. Pneumatic devices may come with a hand pump to be used in the event of device or power failure [11].

Second‐generation LVADs have continuous‐flow rotary pumps. If the device only assists with the work of the left ventricle, the underlying heart function may result in a palpable pulse. If the LVAD is fully replacing the function of the ventricle, there may not be a palpable pulse. As with other technological advances, these devices offer advantages in size, ease of implantation, and durability. The number of moving parts has been reduced to one: the impeller. Second‐generation LVADs are subdivided into devices with axial pumps and those with radial (centrifugal) pumps [11] (Figure 11.2).