Listen to my heart beat, little robot

A new customizable soft robotic sleeve fits around the heart and helps it beat, potentially opening new treatment options for people suffering from heart failure. Importantly, unlike currently available devices that assist heart function, the new sleeve does not directly contact blood, which reduces the risk of clotting and eliminates the need for a patient to take potentially blood thinner medications.

Heart failure affects 41 million people worldwide. Today, some of the options to treat it are mechanical pumps called ventricular assist devices (VADs), which pump blood from the ventricles into the aorta, and heart transplant. While VADs are continuously improving, patients are still at high risk for blood clots and stroke.

To create an entirely new device that doesn't come into contact with blood, the researchers took inspiration from the heart itself. The thin silicone sleeve uses soft pneumatic actuators placed around the heart to mimic the outer muscle layers of the mammalian heart. The actuators twist and compress the sleeve in a similar motion to the beating heart. The device is tethered to an external pump, which uses air to power the soft actuators.

The sleeve can be customized for each patient, said Roche. If a patient has more weakness on the left side of the heart, for example, the actuators can be tuned to give more assistance on that side. The pressure of the actuators can also increase or decrease over time, as the patient's condition evolves.

The sleeve is attached to the heart using a combination of a suction device, sutures and a gel interface to help with friction between the device and the heart, according to the study.