HeartMate I and HeartMate II

HeartMate I

The HeartMate I is implanted alongside the patient's native heart and takes over the pumping ability of the weakened left ventricle.

The device is placed just below the diaphragm in the abdomen. It is attached to the aorta (the main artery that feeds blood into the entire body), leaving natural circulation in place while providing all the energy necessary to propel blood throughout the body. This device is pulsatile, meaning that it simulates the motion of the natural heart. It is approximately four inches in diameter, less than two inches in depth and weighs about two and a half pounds. It can pump up to 10 liters of blood per minute, which restores critical circulation and reverses end-organ dysfunction.

How the HeartMate® I is worn

The system controller and two rechargeable batteries, which provide approximately six hours of mobile patient support, can be worn around the belt or in a shoulder bag. A Power Base Unit (PBU) charges the batteries required for patient support, provides connections for system diagnostics and can provide a direct power connection when desired.

HeartMate II

The Thoratec HeartMate II® Left Ventricular Assist Device (LVAD) is approved as both a bridge-to-transplantation and a destination therapy.The HeartMate ® II LVAD is a next-generation implantable device intended for a broad range of advanced-stage heart failure patients. HeartMate® II is FDA-approved for both bridge-to-transplantation, and as destination therapy for patients ineligible for transplant.

The device's hydrodynamic bearings are designed to provide long-term support.

Its small size makes this VAD suitable for a wider range of candidates, including smaller patients. HeartMate® II provides blood flow through the circulatory system on a continual basis, and its automatic speed control mode regulates pumping activity based on different levels of cardiac activity.

View Heartmate II Animation »

How the HeartMate® II is Worn

HeartMate® II includes a controller and batteries that are attached to an external driveline. A power cable connects the device to a small monitor and a power base unit that can be worn in a pack around the waist or in a shoulder bag. HeartMate® II patients can be discharged from the hospital and monitor the pump at home.

Read about the clinical study that led to FDA approval of this device.

Watch video profiles of patients implanted with the HeartMate II.

HeartMate® II Surgical Procedure

The Thoratec HeartMate II® is approved as both a bridge-to-transplantation and a destination therapy.

How the HeartMate® II is Implanted

The HeartMate® II is implanted just below the diaphragm in the abdomen. It is attached to the bottom of the left ventricle, and to the aorta just above the heart. The device draws blood from the weakened left ventricle and propels it into the aorta, leaving natural circulation in place while providing all of the energy necessary to send blood throughout the body.

The specific technique used to implant a cardiac assist device will vary according to the individual patient and the device selected. The following description of the implantation of a Thoratec HeartMate® II provides a basic overview of the procedure.

Implanting an assist device requires open-heart surgery that lasts from four to eight hours, on average. The surgeon first makes a long incision from the top-center of the patient's chest down to the abdomen. The length of the incision depends on a patient's body size. The HeartMate® II is implanted just below the patient's diaphragm in the abdomen. A small incision is also made in the lower abdomen to allow the HeartMate® driveline to exit the body.

While the surgeon connects the LVAD to the heart, the patient is placed on a heart-lung bypass machine, which takes over the work of the patient's heart and lungs. One tube connects the LVAD pump to the left ventricle of the heart, while another returns to the blood from the pump to the aorta. A small electric motor within the device runs the pump.

Once the device is implanted, the driveline exiting a patient's abdomen is connected to the controller. The controller is connected in turn to the power base. After confirming that the LVAD is functioning properly, surgeons take the patient off heart-lung bypass, close the incision, and bandage both the incision and the driveline exit site.