ACC: PARTNER Finds TAVI as Good as Surgery

MedicalToday

NEW ORLEANS -- High-risk patients who underwent transcatheter aortic valve replacement had virtually the same survival at one year as similar patients who had surgical repair, according to results of the PARTNER trial.

But although the death rates were indistinguishable at one year (24.2% for TAVI versus 26.8% for surgery), the stroke rate was higher for the TAVI patients at 30 days and again at one year, said Michael Mack, MD, who chaired the trial's steering committee.

The rate of major strokes was 3.8% in the TAVI arm versus 2.1% in the surgery arm at 30 days and 5.1% versus 2.4% at one year, that difference that was not statistically significant (P=0.20 at 30 days and 0.07 at one year). When strokes and transient ischemic attacks were considered together there was a statistically significant benefit favoring surgery at both 30 days and one year (P=0.04).

Action Points

  • Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
  • Explain that high-risk patients who underwent transcatheter aortic valve replacement had the same survival at one year as similar patients who had surgical repair.
  • Note that the rate of major strokes was 3.8% in the transcatheter arm versus 2.1% in the surgery arm at 30 days and 5.1% versus 2.4% at one year, statistically significant differences.

The PARTNER results, which were presented today at the American College of Cardiology's annual scientific session, are the first from a randomized trial comparing TAVI with surgery and, as such, Mack said, they do identify a group of patients who could benefit from either procedure.

The trial was designed as a noninferiority trial with the primary endpoint of death from any cause at one year. "It clearly met that endpoint," Mack said.

And although the results for TAVI -- or TAVR as it is also called -- were impressive, so were the results from the surgical arm.

"The 30-day mortality was the lowest that we've seen in any trial to date," Mack told . At 30 days, mortality was 3.4% for TAVI and 6.5% in the surgical arm. "The expected 30-day mortality rate in the surgery arm was 11%," he said.

Aside from the difference in stroke, there was a higher bleeding rate at 30 days in the surgery arm -- 19.5% versus 9.3% -- and a higher rate of new onset atrial fibrillation -- 16% versus 8.6% -- but Mack said those rates were not surprising and are "not worthy of a great deal of focus."

Craig R. Smith, MD, who presented the results at a special showcase session in the ACC's "main tent," said in a statement that TAVI "is the most exciting new treatment for aortic stenosis in the past two to three decades." Smith is the chief of the Division of Cardiothoracic Surgery at New York-Presbyterian Hospital/Columbia University Medical Center and the study's co-principal investigator.

The trial recruited 699 high-risk older patients with severe aortic stenosis and randomly assigned them to TAVI (n=348) or surgery. About two-thirds of the TAVI patients underwent transfemoral procedures while 103 had transapical access procedures. "The success was equally good in both groups," Mack said.

Mack noted that the PARTNER trial recruited patients at 26 high-volume valvular centers, where the surgeons and the interventional cardiologists were not only highly skilled, but also willing to work together closely as members of the same team.

This team approach, the so-called heart team, was initially championed in the SYNTAX trial, which compared CABG with stenting for complex coronary artery disease. The results of that trial demonstrated that stents could be used for some complex cases, but, in general, results were better and more durable with CABG.

The idea of a "heart team" is particularly appealing to those who would like to see an end to turf wars between interventionalists and surgeons and for them, the PARTNER results should be particularly heartening.

"PARTNER takes the SYNTAX heart team and kicks it up to a whole new level," Mack said.

As part of that "new level", he predicted that any scientific statements or guidelines issued about TAVI following the eventual publication of the PARTNER results will "detail the need for a cautious roll-out of this procedure in centers where cardiothoracic surgeons, interventional cardiologists, and general cardiologists are part of the decision team."

The PARTNER results reported here are the second of two PARTNER cohorts to be reported.

Last fall, Martin B. Leon, MD, of Columbia University Medical Center/New York-Presbyterian Hospital in New York City, reported the results from chapter one: Compared with medical therapy, patients who were too sick or too old for surgery had a 20% reduction in one-year mortality by undergoing TAVI to replace narrowed, malfunctioning aortic valves.

Disclosures

The PARTNER trial was sponsored by Edwards Lifesciences.

Mack disclosed lecture fees from Edwards Lifesciences and consulting fees from Medtronic.

Smith disclosed research grants from Edwards Lifesciences.

Primary Source

American College of Cardiology

Source Reference: Smith, C et al "Transcatheter aortic valve implantation versus surgical aortic valve replacement in 'high risk' patients with aortic stenosis: The randomized PARTNER Trial" ACC 2011.