US 'Roadmap' for TAVI Rollout Published

February 01, 2012

February 1, 2012 (Rochester, Minnesota) — A new US expert-consensus document on transcatheter aortic-valve replacement (TAVR) is one of the fastest guidances ever issued, says one of the authors [1,2].

The 105 pages of recommendations were "turbocharged," following the approval of the first transcatheter aortic valve in the US last November--with 48 reviewers and 1100 peer-reviewed comments to sift through--but are "comprehensive, faithful to the evidence, and balanced," says Dr Sanjay Kaul (Cedars-Sinai Heart Institute, Los Angeles, CA), vice chair of the writing committee.

As TAVR--also known as transcatheter aortic valve implantation (TAVI)--is introduced into practice in the US, "detailed and agreed-upon protocols are needed to ensure we achieve optimal clinical results," notes the lead author, American College of Cardiology (ACC) president Dr David R Holmes (Mayo Clinic, Rochester, MN), who stresses that TAVI is a "new, transformational technology."

"We emphasize what we believe are the core issues," Kaul told heartwire . These include: the complexity of TAVI as a technology; careful patient selection; a team-based approach, including specialized "heart centers" and physician expertise in treating valve disorders; proper facilities (hybrid labs or modified cath labs); TAVI screening tests to inform treatment decisions; patient and family education as to the risks and benefits of this procedure; and ongoing evaluation and participation in national TAVI registries to assess real-world outcomes.

We do not want [TAVI] to be seen as an opportunity to generate revenue. It's up to us to make this rollout happen in a careful and thoughtful manner.

"This is a framework," says Kaul. "I hope people will use this as a roadmap for the judicious use of TAVI as it reaches patients across the US. We do not want [TAVI] to be seen as an opportunity to generate revenue but rather to improve quality of life. It's up to us to make this rollout happen in a careful and thoughtful manner."

The consensus document is published in the Journal of the American College of Cardiology and is a follow-up to a joint position statement on TAVI from the ACC and Society for Thoracic Surgeons (STS), issued in mid-2011. A sibling document on operator and institutional requirements for transcatheter valve repair or replacement is also in press [3], notes Kaul.

The Right Patient, at the Right Time, and the Right Place

An estimated 45 000 patients have received TAVI worldwide, with most procedures so far being performed in Europe. US approval of the Edwards Sapien valve at the end of last year means that the country must now gear up to introduce this technology nationwide.

Kaul stressed that patient selection is key for TAVI and is difficult, because, he said, "We currently do not have any TAVI risk models." Decisions on who undergoes TAVI are currently made, in part, on the basis of surgical risk scores, such as the EuroSCORE, and "these are based on coronary artery bypass" and are therefore far from ideal, he notes. New TAVI risk scores are being developed, and Kaul stresses these will play a vital role in better patient selection.

He emphasizes also that TAVI is approved in the US only for those who are deemed "inoperable" with regard to surgical aortic-valve replacement (SAVR) and not for those deemed "high risk" for SAVR. The consensus document notes that TAVI is "recommended" in inoperable patients but that it is simply "a reasonable alternative" to SAVR in patients at high surgical risk. TAVI is not recommended for those with an acceptable surgical risk for SAVR or those with known bicuspid aortic valve, severe mitral annular calcification or regurgitation, or moderate aortic stenosis.

Kaul says very careful weighing of the risks and the benefits for each individual patient "and [communicating these] to the patient and their families" are essential. Because of the lack of TAVI risk scores, it is very easy to "misestimate the predicted risk," he observes, adding that with new procedures, it's likely that "the short-term benefits are overestimated and the long-term benefits underestimated.

"We should not have unrealistic expectations of TAVI. We need to carefully select the right patient at the right time and the right place. We need to think about the utility of the technology vs the futility."

We need to carefully select the right patient at the right time and the right place. We need to think about the utility of the technology vs the futility.

Among the major challenges in trying to weigh risks and benefits of TAVI are the complications, including stroke, which is "dreaded," says Kaul. Most people "would rather die than have a disabling stroke," he observes, adding that only time will tell whether moves to try to reduce stroke rates in TAVI, such as the use of embolic-protection devices, will achieve this aim. "We also have other concerns about durability of the TAVI devices--because we only have two-year data on this from a randomized clinical trial and three to four years of data from registries," he notes. Another issue of concern is paravalvular leak, "which can be a predictor of late mortality," he notes.

Heart-Team, Correct Facilities and Registry Participation Are Essential

Central to the philosophy of this consensus document is a "heart-team–based" approach to TAVI, including the involvement of the primary cardiologist, the cardiovascular surgeon, and the interventional cardiologist, as well as the patient and family. Two surgeons and one cardiologist need to sign off on each patient, the document recommends.

Centers performing TAVI should have experience with structural heart disease, and all team members should be available on-site. In addition, a hybrid surgical room or a specially modified cath lab must be available, as must a postprocedure care team and expert imaging, employing echocardiography and computed tomography.

And ideally all centers performing TAVI will participate in a national registry, the new STS/ACC Transcatheter Valve Therapy (TVT) Registry, "which will help track real-world outcomes," says Kaul, and "could perhaps be linked to reimbursement." Cost-effectiveness will also be an important issue, he notes: "To what extent will society be willing, or expected, to pay?"

The Centers for Medicare & Medicaid Services (CMS) has already opened a "national coverage analysis" for TAVI and will propose a new policy by March 28, with a final decision issued this summer. As such, attendees at the recent Society of Thoracic Surgeons 2012 Annual Meeting insisted that national coverage for TAVI will not repeat mistakes made with Medicare coverage of carotid stenting.

And while Kaul stresses that nothing in the consensus document "is binding," he says that he hopes CMS's "goals are the same as ours."

The consensus document is endorsed by the ACC Foundation, the American Heart Association, the STS, the American Association for Thoracic Surgery, and the Society for Cardiovascular Angiography and Interventions.

Kaul and Holmes reported that they have no conflicts of interest. Disclosures for the coauthors are listed in the paper.