Sunday, September 19, 2010

Robotic Catheter for Hearts

Atrial fibrillation, a heart disorder affecting more than two million Americans is considered a key contributor to blood clots and stroke. Now researchers from North Carolina State University are developing a new computerized catheter that could make the surgical treatment of atrial fibrillation faster, cheaper, and more effective while significantly decreasing radiation exposure related to the treatment plus provide cost savings for hospitals and health insurance companies.

Atrial fibrillation occurs when there is random electrical activity in the upper chambers of the heart, the atria. This causes the heart to operate less efficiently, and can lead to lightheadedness and fatigue. It can also lead to blood pooling in the heart, which contributes to blood clots and increases the risk of stroke.

Today, doctors use a cardiac ablation technique that mitigates fibrillation by inserting a catheter into the heart, and using extreme heat or cold to create small scars through the walls of the affected atria. These scars block the problematic electrical signals. Throughout the procedure, doctors use x-rays to track the tip of the catheter but at this point, exposing the patient and medical personnel to radiation.

Existing commercial catheters are manually controlled and can only move in two directions. These catheters require doctors to painstakingly manipulate the catheter to control exactly where each individual lesion should be applied.

“We are developing a robotic catheter with significantly improved maneuverability and control,” says Dr. Gregory Buckner, a Professor of Mechanical and Aerospace Engineering at North Carolina State and lead researcher for the team.

The new robotic catheter will utilize smart materials to provide significantly better maneuverability and is expected to reduce operating times. The smart materials act as internal muscles, contracting when an electric current is applied. This allows the catheter to bend left, right, up, down or in any combination of those directions.

Doctors will be able to use a specialized joystick to locate key points on the atrium. A computer program can then trace a curve along those points and essentially connecting the dots. This creates a solid line of scar tissue that will then block the electric signals causing fibrillation.

The research team at NC State received a Phase II SBIR grant from NIH in August to take their robotic catheter prototype from the lab and put it into the hands of doctors. The $1.1 million grant will fund two years of development and surgical testing. Half of the funds will go to North Carolina State while the remainder will go to Southeast TechInventures to help bring the technology to the marketplace.

Other groups have commercialized their own robotic catheter designs, but their work requires multimillion dollar capital investments and customized catheter laboratories. The new technology under development at NC State could be made available at a fraction of the cost and help larger number of patients due to significant reductions in initial overhead and operations costs as well as address logistical concerns.