CardioExchange Archive

Key data on what will likely be the second transcatheter aortic valve to gain approval in the U.S. were presented today at the Transcatheter Cardiovascular Therapeutics (TCT) 2013 Conference in San Francisco. Jeffrey Popma, co-principal investigator of the trial, presented the major results from the CoreValve U.S. Pivotal Trial in patients who were too ill or frail for traditional open heart surgery.

In an as-treated analysis of 471 patients (the intention-to-treat population was 487), the primary endpoint — the rate of death or major stroke at 1 year — was 25.5% (CI 21.6-29.4). This was 40.7% lower than the prespecified performance goal of 43% (p<0.0001) based on historical standards.

All-cause mortality was 7.9% at 30 days and 24% at 1 year. Cardiovascular mortality was 7.9% and 17.9%.

The rate of major stroke was 2.4% at 30 days and 4.1% at 1 year.

“The fact that nearly three-quarters of patients were alive and free of strokes at one year is remarkable, given the complex medical conditions and extreme frailty of this population,” said Popma in a Medtronic press release. “Not only do the results meet the CoreValve study’s safety and efficacy endpoints for patients at extreme risk for surgery, but the positive clinical outcomes and low complication rates set a high standard for what transcatheter valves can achieve.”

At 1 year, 90% of patients had a significant improvement in their heart failure symptoms (improvement in at least one NYHA Class) and highly significant changes in quality-of-life scores (27.4 points in the KCCQ scale).

The mean gradient of blood flow was 8.5 mm Hg at 30 days and 8.8 mm Hg at 1 year. Paravalvular leak rates were 11.5% at 30 days and 4.1% at 1 year. Patients with moderate paravalvular leaks did not have an increased risk of death compared with patients with lesser paravalvular leaks.

Major vascular complications occurred in 8.3% at 30 days and 8.5% at 1 year.

At 1 month, 22.2% of patients required a permanent pacemaker. These patients were not at increased risk for death.

Following the release of the trial results, Medtronic announced that the FDA said it would conduct separate reviews for the extreme-risk group studied in this arm of the trial and for the high-risk group (randomized to CoreValve or surgery) participating in a second arm of the trial. Medtronic said that that FDA has determined that it has sufficient information to conduct its review without the need for an advisory panel. The company said it anticipates FDA approval for the extreme-risk patient population by the end of 2014.