This Small Business Innovation Research Phase I project will develop the ?Grip-Act-Reposition (GAR) Miniaturized Stable Working Platform for Minimally Invasive Procedures Inside Active Organs.? Working within or on moving organs ? like the heart or lungs ? is extremely challenging during minimally invasive procedures. The working end of the surgical tool must be deployed through a long (100 cm), narrow (3mm) catheter. The catheter needs significant flexibility to negotiate the path to the target organ - which inherently limits control of the working end. In catheter ablation for treating atrial fibrillation (AF), for example, a radiofrequency ablation catheter creates scar tissue lines to isolate AF sources from the remaining heart. The beating of the heart makes it extremely difficult to attach to the heart wall, burn in the correct depth lesion, and then shift to the next desired ablation position ? resulting in first-time success rates as low as 30% for some forms of AF. The GAR technology platform will enable a tight grip on the heart wall and precision clinician-controlled motion to the next burn location ? and can be integrated in a wide range of medical applications where stable positioning and relocation within a moving organ or body cavity is desired.
The broader impact/commercial potential of this project has several aspects. This project will initiate long-term collaboration between cardiac surgeons and medical device development experts in industry. The Grip-Act-Reposition (GAR) system will ultimately be manufactured in the United States for a large commercial entity that distributes cardiac ablation catheter systems, generating $7.2 million in revenue and 20-30 jobs by 2017. Even greater potential revenue is anticipated when radiofrequency ablation in the left atrium is simplified ? using the GAR approach - and delivered effectively to the more than 2 million potential patients in the United States.
Using the GAR system in cardiac surgery is only the first application. Surgery in the lungs and digestive tract are also complicated by the target organs and tissues moving during the procedure. The GAR approach will gain market share by allowing more effective contact with moving or loose tissues within the body where clinicians are normally limited by the inability of conventional systems to accurately determine and control the position of devices. This project will also engage interns and long term collaboration opportunities with nearby universities, tech schools, and high schools ? with a goal of training future engineers, and also evaluating potential hires.
Atrial fibrillation (AF) affects 2-3 million Americans, costing the healthcare system an estimated $6.65 billion/year to treat. One of the most common procedures for stopping future AF events from occurring is Radiofrequency (RF) Catheter Ablation. A specialized catheter with a metallic tip is used to deliver high frequency electrical current to tissue. The current locally heats tissue and creates a lesion in the heart wall. Numerous individual lesions are then created in attempt to form linear patterns that will produce a conduction block to isolate the AF trigger sources (commonly located in the pulmonary veins). Inconsistent and unstable placements of the RF ablation catheter tip during the procedure can result in long procedure times (often as long as 4 hours) and lesion patterns that are disjointed or of insufficient ablation depth to be effective. Thus, the success rate (i.e. long-term elimination of AF) following a single catheter ablation procedure is highly variable, estimated only in the range of 30-80% of patients. Minimally-invasive surgical interventions require deployment surgical tools and effectors through small incisions. Many interventional procedures, including those in the brain and heart, utilize flexible and steerable catheters to access the treatment area, sometimes a substantial distance (tens of centimeters) from the incision site. Manipulation of the distal tip of existing devices in this context is performed externally with extremely limited tactile and visual confirmation of position. The moving tissue in the heart for AF treatment, or other locations (intestines, lungs) makes it extremely difficult to hold a position, or reliably move to a new location. In the SBIR Phase I and IB projects, Actuated Medical, Inc. (AMI) partnered with Leland Stanford Junior University (Stanford) clinicians to successfully design, build, and evaluate the Grip-Act-Reposition (GAR) catheter system to securely grip and move along the endocardial wall of the heart while producing continuous lesions at consistent depth. The GAR platform has the potential to revolutionize cardiac ablation by improving success rates and lower costs and complications. Additional work during Phase I B focused on evaluation in intestinal tissue for endoscopic applications. Minimally invasive surgeons are extremely interested in the potential of the GAR system to treat a number of challenges and conditions. Another successful goal of the project has been to increase collaboration and technical knowledge exchanges between university and commercial partners.