Video of Human AVBG Procedure (on Pump)

As I have mentioned, aortic valve bypass procedures are currently being performed by cardiac surgeons around the world.  Using generally “on pump” techniques, surgeons employ components off label to create an integrated implant at the time of surgery.

A good example of the procedure basics is shown in a video recently posted on the CTSNet web site. In the video, an AVBG “on pump” procedure is performed by Drs. Heyman Luckraz, Adam Szafranek, Christine NH Tan, and Peter A. O’Keefe at University Hospital of Wales, Cardiff, United Kingdom. The procedure was performed on a 49 year old male presenting with significant aortic stenosis (0.8 EOA / 75 mm Hg gradient), native diffuse CAD, previous CABG, and previous aortic coarctation repair. I’m sure this patient would be considered extremely high risk for conventional aortic valve replacement.

Apical access was achieved using fem/fem bypass and ventricular pacing.  With our technology (still in animal studies) we  do the entire procedure off pump on a normally beating heart.

Nonetheless, the Cardiff results were excellent. I was especially impressed with the post operative CT reconstruction showing the implanted conduit.  After seeing this image, one can appreciate how AVBG might be considered analogous to CABG (or should I say OPAVB to OPCAB).

AVBG in the News

James S. Gammie, M.D., Associate Professor of Surgery, Maryland Heart Center

James S. Gammie, M.D., Associate Professor of Surgery, Maryland Heart Center

Dr. James Gammie, a cardiac surgeon at the University of Maryland, has performed many AVBG (Aortic Valve Bypass Graft) procedures over the past few years.

Recently, Shelly Wood, a reporter for heartwire, did a story on his work in this area.  The article is titled Aortic-valve bypass: A time-tested, minimally invasive alternative to valve-replacement surgery.   I think Ms. Wood did an excellent job explaining the procedure and Dr. Gammie’s clinical experience.  Below is an excerpt from her article.

But Gammie believes that AV-bypass surgery would likely compete directly with transcatheter aortic-valve replacement and indeed has several advantages.

For one, a wide range of valve prosthetics can be used in the apicoaortic conduit-those used in Gammie et al’s study have a long track record of safety and durability, he notes. Likewise, the procedure itself, while not widely used, has proven its durability. “There are people walking around today who had this operation a quarter century ago,” Gammie points out. “So we know it’s a durable approach.”

Third, there is no disruption to the native valve and no permanent prosthetic forced over the calcified valve leaflets, thus reducing the risk of both perioperative and long-term stroke. There’s also no risk of heart block-a side effect seen following the implantation of permanent percutaneously placed devices, Gammie notes. Finally, perivalvular leak is not a potential problem, since the device does not need to be sized within the native valve. “So patient-prosthetic mismatch is not a problem,” he said.

On a more hypothetical note, Gammie said that he and his colleagues are testing whether diverting blood flow away from the calcified native valve would in itself decrease stroke rates over the long term. Preliminary analysis suggests that roughly two-thirds of the blood volume may be diverted through the conduit, a rerouting that may prove beneficial over time. “Our hypothesis, which we haven’t proven yet, is that AV bypass surgery may be ‘brain-protective,’ because of the blood flow configuration in the long term,” he speculated.

Why is Cardious developing an Aortic Valve Bypass Graft?

Short answer – we don’t think it is prudent to throw the baby out with the bathwater.

Now the longer answer.

Prior to starting Cardious, my partner Kem Schankereli and I were consulting for a stent valve start-up company.  After given the basic concept by the physician founder, our job was to design and build a working prototype of a catheter delivered expandable aortic heart valve.  With my background in interventional catheters and Kem’s in heart valves, we were well suited to the task.  After initial animal studies, it became apparent to us that a stent valve was a high potential concept, but packaged in a myriad of significant development challenges.  In our experience, we have come to understand the “zen” of a successful implantable medical device.  That is, the key to an implant product’s success is to leverage knowledge and experience to make the implant simple.

Stent valves and the related implant procedure are not simple.
Read More »

Welcome to Cardious and the Cardious blog

Welcome to the Cardious website… and this Cardious blog. My name is Jim Pokorney, and I am a founder and president of the company.

Within this site you will find a description of Cardious Inc., an emerging medical device company located in St. Paul, MN.  Cardious is focused on the development of a less invasive aortic heart valve therapy that allows a traditional heart valve (manufactured by others) to be surgically installed into a beating heart.

We encourage your participation during our development process, especially if you are a cardiac surgeon, a biomedical professional, or an active investor. To that end, we will be posting articles (and opinions) about our product and will be looking forward to your comments and responses. After reviewing our site, please contact us if you would like to learn more about our company.

Our product is not yet approved for human use.  We are currently in animal studies.  If all goes well, we plan to perform our first human implant in the later half of 2010.

I welcome comments on any of our blog posts from our readers. Please keep them brief and include your full name and profession (for publication purposes). We reserve the right to publish responses elsewhere and to edit them for content as well as length.