Sapien transcatheter aortic valve Source: Edwards Lifesciences

The FDA granted approval Nov. 2 for the transfemoral delivery of the Sapien transcatheter aortic heart valve (Edwards Lifesciences) for the treatment of inoperable patients with severe symptomatic aortic stenosis. American College of Cardiology (ACC) President David R. Holmes, MD, expressed excitement about the approval of this “transformational technology,” but recognized that there are some hurdles ahead for implementing the device into real-life clinical practice.

This is the first U.S. commercial approval for a transcatheter device enabling aortic valve replacement without the need for open-heart surgery. Transcatheter aortic valve implantation (TAVI) will allow multidisciplinary teams of interventionalists and surgeons to replace a patient's diseased aortic valve without traditional open-heart surgery.

“Although surgical valve replacement is a Class I indication for the treatment of severe aortic stenosis, there is a substantial population of patients—perhaps 30 to 40 percent of patients with severe aortic stenosis—who do not receive that Class I indication, either because they are too high risk or do not choose to undergo surgery,” explained Holmes, an interventional cardiologist at Mayo Clinic in Rochester, Minn. “This technology directly addresses that unmet clinical need in the U.S. Unfortunately, this patient population, when treated with balloon valvuloplasty or medical therapy, has very poor outcomes.”

“The Sapien valve is indicated for transfemoral delivery in patients with severe symptomatic native aortic valve stenosis who have been determined by a cardiac surgeon to be inoperable for open aortic valve replacement and in whom existing comorbidities would not preclude the expected benefit from correction of the aortic stenosis,” according to the Irvine, Calif.-based Edwards

The safety and effectiveness of the Sapien transcatheter valve were evaluated for patients who could not undergo surgery in the randomized, controlled pivotal PARTNER Trial, Cohort B. Additional analysis of data from Cohort B demonstrated that patients receiving the Sapien valve experienced a substantially better quality of life as compared to the control group patients, and also that TAVI was cost-effective. “This trial showed a 20 percent improvement in survival in those patients treated with TAVI,” Holmes said. “This presents U.S. patients with severe aortic stenosis with an option they didn’t previously have.”

In July, the FDA’s Circulatory System Device Panel favored TAVI approval in the U.S. The panel voted on three items, including: safety, effectiveness and whether the benefits outweighed the risks. If the FDA accepts panel recommendations, TAVI procedures would be available to U.S. patients.

The FDA did not place any stipulations on its approval in terms of operator or facility volume, as was discussed at the panel. “It is in the best interest of patients and professional societies to make sure this technology is used in expert centers by expert physicians in the right patient population, so as to optimize results,” Holmes said. “The hope is that there are specialized centers that focus on valvular heart disease.”

While Holmes said that no one can predict how the Centers for Medicare & Medicaid Services (CMS) will respond with regards to reimbursement, the ACC and the Society of Thoracic Surgeons (STS) previously requested that CMS review the possibility of covering TAVI after it received a formal national coverage determination—which it did in September.

However, CMS noted in September that it is aware of the high stroke and death rates associated with TAVI, and said that it remains concerned about adverse events that may occur, particularly when the procedure is performed by less experienced operators. Rates of stroke and death at 30 days were 6.7 percent and 5 percent, respectively, for those who received TAVI. At one year, these rates were 10.6 percent and 30.7 percent.

“While there are clearly risks associated with the TAVI procedure, we must remember that this patient population was too high risk for surgery,” said Holmes, adding that the benefits outweigh the risks. “When you calculate the number needed to treat to save a life, it’s very small.”

As part of this approval, the FDA has requested the implementation of two substantial post-approval studies. One study will follow patients already enrolled in the PARTNER Trial, and the second study will track new U.S. patients. The company anticipates the second study will be incorporated into a new national patient registry.

Holmes suggested that the design of these trials will evolve, along with the ongoing conversations between Edwards and the FDA. However, both the ACC and STS are involved in the development of a transcatheter valvular therapy (TVT), which “hopefully be part of the post-approval studies,” he said.

As STS President Michael J. Mack, MD, said in a statement, “The STS is pleased to have the opportunity to work with the ACC, the FDA, CMS and Edwards Lifesciences in a coordinated effort to optimize patient safety, including the use of specialized heart centers with multidisciplinary heart teams, operator training and credentialing standards, and the establishment of a National TVT Registry to track and monitor patient outcomes.”

“This is a technology that will change how we practice cardiovascular medicine for a substantial number of patients with severe aortic stenosis,” Holmes concluded.