In 2004, after a 10-year study in patients, the US Food and Drug Administration (FDA) approved the SynCardia temporary Total Artificial Heart (previously called the CardioWest total artificial heart) as a bridge to heart transplantation in patients who have end-stage biventricular failure. When patients have biventricular failure, it means that they have heart failure affecting both sides of the heart. In most patients, the SynCardia helps restore blood flow and improves organ function, making these patients better transplant candidates when a donor heart is found. Also, patients usually see an improvement in their activity levels and their overall quality of life.
Surgeons are using this device in patients at THI. In fact, in 2011, THI surgeons implanted the SynCardia device in 4 patients over a 12-day period, bringing the total number of these devices implanted worldwide to more than 950.
The Pump
The SynCardia is an air-driven (pneumatic) pulsatile pump that replaces both of the patient's own ventricles and all 4 of the patient's heart valves. The pump is lined with polyurethane. Its 4-layer, air-driven diaphragm can pump blood through both of its "ventricles" at up to 9.5 liters per minute. Inside the pump, a vacuum is created by the pneumatic driver, which pulls the diaphragm down so blood can enter the ventricle. A pulse of air then pushes the diaphragm back to the top of the ventricle, pushing the blood out.
The Console
The SynCardia is powered by a pneumatic driver located in a nonportable console that weighs 418 pounds, so patients must stay in the hospital while they have the device. All of the sensors, motors, and electronics that power the SynCardia are located outside the body in this pneumatic driver, which eliminates the need to reoperate to repair faulty electronics within the artificial heart itself.
In Europe, a new, wearable driver system has been approved, allowing patients to leave the hospital while they await a donor heart. Weighing slightly more than 13 pounds, this wearable driver system is designed to be carried by the patient in a backpack or shoulder bag. SynCardia is currently conducting an FDA-approved study of the portable driver so it can be made available in the United States.
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