A new study has revealed how an implantable soft robotic device can mimic the natural motion of cardiac muscles, thereby giving the organ gentle squeezes and helping failing hearts pump blood.

There are over five million heart failures in the U.S per year, costing the nation an estimated $32 billion each year. Internationally, this serious condition afflicts 41 million people. The soft robotic device is silicon based and it relaxes or stiffens when inflated with pressurized air. It is hoped that the device could prove to be a promising strategy for the development of assistive devices for heart failure.

Ventricular assist devices (VADs) currently used as a life-prolonging therapy, are in constant contact with the blood. This requires the use of long-term blood-thinning medications as a patient’s risk for coagulation, stroke and infection is increased. Another drawback is that the VADs interfere with the contraction mechanics of the heart and its normal curvature.

In an effort to find a more effective device, Ellen Roche and colleagues developed the soft device and designed it to augment cardiac function, instead of disrupting it. They achieved this by reproducing normal heart muscle behavior closely.

Video Credit: Roche et al., Science Translational Medicine (2017)

The device synchronized with native heart motion and successfully conformed to porcine heart surfaces in ex vivo experiments. After acute cardiac arrest, it also managed to restore normal blood flow in six live pigs. By selectively compressing and twisting either the left or right ventricle of explanted pig hearts, the researchers were able to “fine tune” the device. This is a key finding as chronic heart failure often only affects a specific part of the heart.

Once further investigation has been done, the device could possibly be tailored for individual patient needs to target cardiac recovery or rehabilitation better. The authors do caution that additional work is required before this technology would be suitable for longer-term implantation in the body.

The research, including a proof-of-concept experiment with live pigs, was published in Science Translational Medicine.