Israeli device cuts risk during heart surgery

By Rivka Borochov

Open-heart surgery for people with aortic stenosis - where the heart valve doesn't open properly - is tricky and dangerous, especially for older patients with existing medical conditions. And a new approach now being reviewed by the US Food and Drug Administration (FDA) comes with a high chance of stroke on the operating table.

However, thanks to an Israeli cardiologist, it is now possible to lower the risks involved in the promising procedure called transcatheter aortic valve implantation (TAVI for short), whereby a synthetic valve is ferried to the heart through a small incision in the groin area.

The TAVI procedure was pioneered in Europe and is similar to a balloon angioplasty, where a stent is inserted into an artery. The catch is that up to 15 percent of the time, a piece of calcified artery comes loose and may cause a stroke if it travels into the brain.

Israeli cardiologist Dr. Dov Shimon has developed a filter against the embolisms caused during TAVI procedures, reducing the likelihood that a patient will suffer a stroke. His device, developed by SMT Research and Development in Herzliya Pituach, has so far been successfully tested on 15 people in Holland. That means Shimon has already beat the statistics.

Prepping for FDA clearance

According to MRI results, post-procedure brain lesions are present in up to 91 percent of people who have undergone a TAVI procedure, indicating an estimated three percent to 10% risk of stroke. While TAVI is by far one of the most promising advances in cardiology, Shimon anticipated the problem and determined to get around it. To this end, the SMT team - now a group of seven, plus consultants - has spent five years developing and refining a medical device specifically designed to reduce the chance of stroke during TAVI and other cardiac procedures.

Positioning the filter at the arch of the aorta, the SMT device covers all three arteries branching off the aorta. Other solutions on the market, from CoreValve and Edwards Lifesciences, cover only one artery.

"Current TAVI devices are working well, but despite efforts to refine the technique, we continue to see post-procedure complications associated with cerebral embolism resulting in stroke and other ischemic events," says Shimon, who founded SMT.

Inserted before the two-hour operation and removed afterward, the SMT filter appears to successfully prevent dislodged hardened artery materials from migrating into the arteries. Paul Zalesky, SMT's CEO, says that in the future it may be possible to leave the filter in place permanently.

A new $10.5 million investment by a New York venture capital firm, on top of the company's previous $4.5 million in investments, will help get the SMT product to the market once the TAVI procedure is deemed safe by the FDA. This could happen within the next year.

Tested in Holland and pleased with the outcome

Zalesky explains that TAVI is an example of a less invasive interventional cardiology procedure, an increasingly attractive alternative to open-heart surgery. The operation involves threading surgical tools into a blood vessel through the leg and up into the heart. It is especially suitable for older men with chronic heart issues who could not withstand open-heart surgery.

Dr. Pieter Stella, from the University Medical Center in Utrecht, the Netherlands, said the SMT device "is the first embolic protection device that I have seen that offers coverage of all three primary vessels feeding the brain. I have been pleased with our early results, and believe that the SMT deflector will help to ensure the continued market expansion for safe, effective TAVI procedures."

Founded in 2005, SMT hopes to start its clinical trials in the United States in 2012.

www.mfa.gov.il/MFA/InnovativeIsrael/Israeli_device_cuts_risk_heart_surgery-July_2011.htm