This new robotic catheter will make heart surgeries safer

Less invasive methods involve threading catheters through the body's vasculature to reach the heart, but they come with significant drawbacks. These catheters are easily displaced by beating heart tissue due to their size, and their lack of dexterity makes reaching the target tissue challenging. 

Finding a solution requires being both small and large, rigid and maneuverable, seemingly contradictory demands.

An innovative design.

To address these challenges, the team, led by senior author Tommaso Ranzani, Ph.D., devised a robotic catheter with specific properties tailored to each phase of a procedure. 

The catheter features a flexible, air pressure-operated tip thin enough to navigate veins but can inflate once inside the heart for added stability. An expandable ring offers further stability, anchoring the catheter in place by pushing against the vein walls. 

The dual functionality offered by the tip and the ring allows the robotic catheter to pierce beating heart tissue without being dislodged, enabling surgeons to perform intricate procedures with the required control and precision. 

Successful trials and prospects.

The team showcased the abilities of the robotic catheter in a setting with realistic anatomy by simulating trials on an ex vivo pig heart.

In the first of two trials, a pacemaker lead placement in which a guidewire is inserted into the wall of the right atrium, five inexperienced operators successfully completed the procedure using the robotic catheter in a comparable time frame to an experienced physician using a standard catheter. 

The second trial was the first step of a tricuspid valve repair procedure, a more challenging operation typically performed through open-heart surgery. This procedure involves fastening a ring around an opening and closing heart valve.

Looking ahead, the researchers plan to advance their technology by conducting live experiments on more complex procedures, aiming to reduce the reliance on taxing open-heart surgeries.

"As we discuss these results with physicians working in the field, we see a high level of enthusiasm and hear of more and more applications for this technology," said Ranzani, in a statement. 

With the potential to make procedures safer, less invasive, and more accessible to a broader range of patients, the robotic catheter, funded by grants from NIBIB, the National Center for Advancing Translational Sciences, and the Department of Energy, may pave the way for a new era in cardiac care.

Study Abstract

In minimally invasive endovascular procedures, surgeons rely on catheters with low dexterity and high aspect ratios to reach an anatomical target. However, the environment inside the beating heart presents a combination of challenges unique to few anatomic locations, making it difficult for interventional tools to maneuver dexterously and apply substantial forces on an intracardiac target. We demonstrate a millimeter-scale soft robotic platform that can deploy and self-stabilize at the entrance to the heart, and guide existing interventional tools toward a target site. In two exemplar intracardiac procedures within the right atrium, the robotic platform provides enough dexterity to reach multiple anatomical targets, enough stability to maintain constant contact on motile targets, and enough mechanical leverage to generate newton-level forces. Because the device addresses ongoing challenges in minimally invasive intracardiac intervention, it may enable the further development of catheter-based interventions.