13/2 Improvements of the anastomotic device to maximise the success rate of the animal trials

		Cobra Tool The core pieces of the COBRA are two grooved helical needles carrying the threads and six small metall hooks to hold the vessels in place. COBRA with the memory metal hooks

In the course of the Co-Me phase 1 project "Cardiac Robotics", a semi-automated suturing process involving a new device called «Cobra-Tool» with a helical needle and drive unit has been developed. The system produces semi-automatically continuous suture anastomosis using polypropylene threads. Using this novel device, conventional mammary artery grafts to coronary artery end-to-side anastomosis on explanted pig and sheep hearts have successfully been performed. There are six patents pending for the Cobra Tool.

Experiences from development in Co-Me phase 1 showed that the technology transfer of a successful laboratory trial to a successful animal trial requires continuous evolution of the device in a close collaboration between the engineers and the cardiac surgeons. The tests revealed main fields of improvements required. Addressing these is subject to the Co-Me phase 2 research and development work.

The research and development fields of this project include:

• the reduction of the time required for the placement of the Cobra tool, which, at the end of Co-Me phase 1, took 15-20 minutes for an untrained cardiac surgeon
  
• testing and optimising the grooved needle used to transport the suture through the tissue, in order to guarantee fast and hassle free operation.
  
• improvement and adaptation to the new tool design of supporting tools the like the LIMA inversion tool
  
• improvement of the helical needle drive set, and, in addition, development of a needle servo drive unit.
  
• performance of a successful anastomosis in a live animal. This test will be followed by long term animal experiments with 6 month follow-up to determine late patency of the anastomosis after the healing process is complete. The animal experiments will also serve as a preparatory pilot study for getting certification from regulatory authorities for performing the first human trials.
  

At the end of the second year, the anastomotic device is planned to be ready for clinical trials and next industrialisation steps performed with industrial partners.