Jordan Pollack saw a problem. While he, and his three other LifeSAVR Solution Founders, were in graduate school at the University of Michigan, they observed a transcatheter aortic valve replacement (TAVR) surgery at Beaumount Hospital in Royal Oak, Michigan. This minimally invasive procedure uses a catheter and guidewire to replace diseased aortic valves in the heart. But the only way to visualize this internal procedure, and ensure correct placement of the new valve, was through fluoroscopic guidance, or fluoro. Using fluoro, the whole procedure is visualized in real time by X-rays projected on a screen above the patient. Fluoro and physician experience are the only way to know that the replacement valve is in the right location before it’s deployed. Jordan and his other classmates felt there had to be some better way to ensure proper valve placement during TAVRs that didn’t rely solely on just a 2D image and a good bit of guessing.
Aortic valve disease, or aortic stenosis, is a large problem in the US and is especially prevalent in the elderly. One study estimated that every one in eight people over the age of seventy-five in has moderate to severe aortic stenosis.
Replacement of the aortic valve via open heart surgery is the gold standard for aortic stenosis treatment. During this process, patients are opened up, the old, diseased aortic valve is excised, a new valve is sutured into place, and the patient is closed back up. These replacement valves implanted during surgery are usually metal based and inserted during a procedure that lasts for several hours. Afterwards, patients usually have a two-week hospital stay, followed by several weeks of recovery.
TAVR first hit the market in Europe in 2006-2007 and entered the US commercially in 2011. TAVR was given FDA approval in the US only for high risk patients with aortic stenosis, those for which surgery would be too risky to complete.
Approximately 300 to 500K elderly US patients are eligible for this minimally invasive procedure. As opposed to open heart surgery, TAVR is a catheter lab procedure that takes ninety minutes or less to complete. During the procedure, a three-meter guidewire is traced up an artery, usually the femoral artery in the leg, with fluoro guidance. The guidewire runs all the way up the artery to the aorta, through the diseased valve, and into the left ventricle. The operating physician then uses a balloon to expand the damaged, narrowed valve. The balloon is removed and the new, prosthetic valve is traced along the guidewire path with a catheter, until it reaches the diseased valve. Most current valves used in TAVR are self-expanding and made up of valve leaflets from pig or cow pericardium, as opposed to the metallic valves used in open heart surgery.
TAVR has been successful and there are promising results from clinical trials in high risk patients. “The push is to make TAVR the goal standard to completely replace open heart surgery,” explains Jordan.
There are some potential issues with TAVR that have slowed down the process for the procedure to become the standard of care for aortic stenosis treatment. “The big thing is longevity. No one really knows how long these valves [used in TAVR] will last,” says Jordan. The field is just beginning to see the first patients who have had TAVR replaced valves for ten years.
The other problem compared to open heart surgery is the general…murkiness of the whole process. Physicians aren’t opening up a person like in open heart surgery and are relying on fluoro and 2D images to determine if a valve is in place before it’s deployed- a process that leads to 3-5% of TAVR valves being acutely misplaced, which can lead to perivalvular leak.
Valves can also be chronically misplaced, where they are just slightly misaligned or shift overtime from excessive calcification. Besides health implications to the patient, misplaced valves are pricey. Each valve costs $40K to replace, which has to be assumed by the hospital system in cases of valve misplacement by the physician.
“That’s really the problem that we’re trying to solve, is valve misplacement during the TAVR procedure,” explains Jordan.
Jordan and his three-person team of University of Michigan graduates founded LifeSAVR Solutions and are developing a product called the Corfinder; “cor” is the Latin word for heart. Their product will provide “quantitative, adjunctive confidence for physicians to know that he or she has place the valve properly.” The Corfinder is not meant to replace fluoroscopic guidance or physician experience, but to complement them. The team is creating this specialized guidewire, the Corfinder, with a series of sensors along the distal tip. The Corfinder will help to refine detection of the native valve during TAVR procedures and ensure better alignment between the annulus, or base, of the new prosthetic valve and old, diseased valve.
The LifeSAVR Solutions team is currently in the technology and feasibility stage of the process. They are incorporating the tiny sensors onto the guidewire and are getting the product down to a functional form factor.
Jordan has found some great resources in the Twin Cities to help the team with this process. In CoCreateX, he found a group where he could interact with people doing similar types of things. However, “…the biggest community that’s provided me with connections is the Jewish community,” he notes.