Device helps correct atrial fibrillation

Paul Mayne // Western NewsWestern Biomedical Engineering PhD student Danny Gelman runs through tests using his catheter contact-force controller. This tool, an add-on to existing commercially used catheters, is able to stabilize contact-force during delivery of catheter ablation for patients with irregular heartbeats. The hope is to improve procedure success rates, improve patients’ quality of life and reduce health-care costs.

A patient with an irregular heartbeat often requires multiple hospital visits and procedures, called catheter ablation treatments, to restore the heart to good health. One Western Biomedical Engineering PhD student, however, is using robotics to change that to a ‘one-and-done’ procedure.

With a background in electrical and computer engineering, Danny Gelman is developing devices with the potential to improve cardiovascular interventions – taking instruments used clinically and attaching them to a robot in order to manipulate those instruments more effectively.

This includes a new add-on device, called a catheter contact-force controller (CFC), that could revolutionize the procedure used to repair a common, troublesome heart problem.

Cardiac arrhythmia can lead to blood clots, stroke, heart failure and other heart-related complications. One of the most common is atrial fibrillation (also called AFib), in which two upper chambers of the heart beat out of rhythm, or quiver.

Catheter ablation selectively destroys tiny areas of the heart tissue causing the fibrillation.

Using electrodes that create heat, ablation creates scarring around the opening of pulmonary veins, a procedure that stops the extra pulse and brings normal rhythm back.

The procedure, which costs $25,000 – $30,000, restores the patient to health.

“There has been a lot of innovation and progress made, but one in two (patients) have to come back for another treatment,” said Gelman. That’s because the standard ablation process sometimes leaves gaps between healthy tissue and scar tissue that can lead to renewed fibrillation, and to yet another catheterization at a later time.

One reason is the difficulty in maintaining desired contact-force between the catheter and the heart wall, while the heart muscle and respiratory system contract and expand.

Gelman’s catheter contact-force controller, which he is looking to commercialize through the Proteus Innovation Competition, helps solve that issue.

This add-on tool is able to stabilize contact-force during delivery – increasing the procedure’s efficacy while improving patients’ quality of life and reducing health-care costs.

He said the CFC can maintain contact with the moving tissue and autonomously positions the ablation catheter to meet a consistent desired force level, regardless of the cardiorespiratory motion. Embedded electronics monitor contact-force in real-time.

“When you first get diagnosed, they try and treat your rhythm control using drugs,” said Gelman. “The last line of defence was catheter ablation, but now it’s more commonly becoming the first line of defence. The problem has been we can control two of three metrics – how much power we are delivering to the tissue and how long we are doing the ablation – but we can’t control the contact force because the heart is beating, and the patient is breathing, during the procedure. Physicians can’t really compensate for those changes in force.

“But with this small hand tool, which can be added to existing catheters, it gives the physicians control over how much force they want. It maintains the same amount of force at all times. They can now control all three – power, time and amount of force. We can deliver the same reproducible ablation lesion regardless of the type of motion, and that becomes a very powerful tool.”

* The Proteus Innovation Competition is a four-month challenge, as part of Western’s Propel accelerator, to create a viable commercialization strategy for one of three promising technologies. Competitors will hone their business skills, work with experienced advisors, accelerate commercialization on discoveries coming out of London’s top institutions and vie for a $5,000 prize, said Ian Haase, Director of Entrepreneurship (Propel). Proteus is open to anyone in the community older than 18 with an interest in developing their business skills and creating new networks.