BARCELONA, Spain — Implanting aortic heart valves without cracking chests opens a new frontier for interventional cardiology that is expected to grow to $700 million in just four years, according to figures from Millennium Research presented at EuroPCR 2008, being held here this week.

With an unpleasant 10-year history of pushing cardiac surgeons aside with stent implant procedures, the European Association for Percutaneous Cardiovascular Interventions (EAPCI) is going to great lengths to assure and not threaten surgeons with this new alternative procedure.

The theme for EuroPCR this year is "Working Together" to emphasize the main message that transcatheter aortic valve implantation (TAVI) will be a team effort between the cardiologist and the surgeon.

For this year's opening plenary session, "The Great Debate," EAPCI for the first time featured three surgeons on the panel to demonstrate that the new treatment will be based on collaboration and cooperation and not the fratricidal infighting that marked percutaneous cardiac stenting.

The goodwill lasted a day and a half before the first fracture lines appeared in the new landscape painted by EAPCI.

At the conclusion of his keynote address, "Transcatheter Aortic Valve Implantation: A State-Of-The-Art," Patrick Serruys, MD, from the prestigious Thoraxcenter at Erasmus University (Rotterdam, the Netherlands), said he predicted a progression where "the procedure will begin as it should, with the percutaneous interventionalists working with a cardiac surgeon who is on-site, making up the 'heart team.'"

Then, he said, there will be the percutaneous cardiovascular intervention (PCI) teams, with a lesser degree of involvement by the surgeons, and finally PCI centers that will launch without surgeons.

"You can bet on this happening," Serruys said.

For the moment, TAVI procedures are indicated only for high-risk patients with severe aortic stenosis who are also not eligible for conventional surgery.

In the opening EuroPCR press conference, Carlos Ruiz, MD, director of structural and congenital heart disease at Lenox Hill Hospital (New York), said that offering a high-risk procedure with unknown long-term benefits to the highest-risk population "is logical."

"The true danger would be to offer such a procedure to someone who is at a low or moderate risk," he told Medical Device Daily. "This would be unethical, not to provide this patient with the 'gold standard' of surgical implantation."

Having said that, Ruiz smiled, adding, "Of course, if we are able to show safety among the patients at the highest risk, then the case for expanding to the lower-risk patients will be logical and stronger."

In building the case for TAVI, Serruys said, "The bottom line is that 20% of patients with aortic stenosis are candidates for this procedure.

"We are aging in Europe," he said, calculating that in an elderly population estimated at 77 million today, there are 3 million persons with aortic stenosis, and therefore 600,000 cases that should be reviewed for surgical valve replacement.

Yet today only 60,000 such procedures are performed by surgeons, he said, leaving "a rather large under-treated population."

The driver for percutaneous valve replacement is these demographics, he said, the ability to provide an alternative for high risk patients that results in less post operative pain and complications.

And he said the emergence of an alliance between cardiologists and cardiac surgeons should not be underestimated as a potential driver for wider adoption, as opposed to becoming a source of conflict.

Martyn Thomas, MD, clinical director of cardiothoracic services at St. Thomas' Hospital (London) described several reasons why surgeons are essential to the team.

"We are the gatekeeper for the patient entering the process, and I believe we should remain the gatekeeper for this procedure as well," he said.

Another proof that surgery is integral to the procedure came in the quick consensus among panelists that TAVI requires a dedicated hybrid facility combining a cath lab with an operating theater.

Showing a photo of a recent procedure at St. Thomas, Thomas highlighted that there were eight people in the current cath lab, and that "it can get quite cozy."

The heart valve team for a high-volume center needs to be comprised of two experienced operators for the catheter, two surgeons with joint training in the procedure, and a cross-trained nursing and support staff, he said.

"This truly takes a team effort, with expertise for imaging, anesthesia and nursing," Thomas said.

In his summary of the state of the market, Serruys said the proof of concept for TAVI is validated with some 2,000 patients having received either a ReValving System from CoreValve (Irvine, California) or a Sapien valve from Edwards Lifesciences (also Irvine).

The quality, safety and efficacy are there, he said, concluding an even-handed presentation of results from the two companies' products.

No failure has been detected for any of the valves, he said.

Each company experienced a learning curve at launch that resulted in a 15% morbidity rates at 30 days, but which then dropped for both products to an 8% morbidity that has been sustained.

The medium-term survival rates are good for both products, Serruys said, showing follow up data where hovering in the 80% neighborhood.

"As for cost-effectiveness and comparisons to alternative procedures, we simply do not know yet," he said, adding that the cost effectiveness proofs will come in time and that this will greatly aid its general adoption.

"We know the money is there," he said, adding that the greatest hurdle in Europe will be winning the necessary reimbursement.

Looking ahead, Serruys said there is already a next generation of aortic valves under development "that address limitations found in the first-generation valves."

He said that Direct Flow Medical (Santa Rosa, California) has enrolled its first patients for clinical trials in Europe.

He also highlighted the development of two innovations, the Sadra Lotus Valve System from Sadra Medical (Saratoga, California) with a self-expanding valve using a nitinol frame that shortens as it is deployed, generating radial force for anchoring, and the PercValve from Advanced Bio Prosthetic Surfaces (San Antonio) that applies nanotechnology to create an eNitinol membrane.