The results of a pivotal clinical study of high-risk surgical patients with severe aortic stenosis treated in Cohort A of the PARTNER trial demonstrate that, at one year, survival of patients treated with transcatheter aortic valve implantation (TAVI) was equivalent to those treated with surgical aortic valve replacement.
The data were presented at the American College of Cardiology’s Scientific Session in New Orleans, USA.
In patients with aortic stenosis at high risk for surgery, TAVI with the Sapien transcatheter aortic valve (Edwards Lifesciences) was non-inferior to surgical aortic valve replacement for all-cause mortality at one year, 24.2% vs. 26.8%, respectively. Mortality at 30 days was lower than expected in both arms of the trial, with TAVI at 3.4% and aortic valve replacement at 6.5%, said Craig R Smith, chief of the Division of Cardiothoracic Surgery at New York-Presbyterian Hospital/Columbia University Medical Center and the study’s co-principal investigator. The observed mortality in these aortic valve replacement patients was lower than the predicted risk of operative mortality of 11.8%. Even with this early generation device and limited operator experience, the TAVI mortality was the lowest reported in any multicentre series of clinical data for the Sapien valve.
“This study shows that TAVI is statistically non-inferior to the gold standard surgical procedure in a high-risk population. This opens up a new set of patients who will benefit from TAVI,” he told delegates.
Both TAVI and aortic valve replacement were associated with important but different periprocedural hazards. The study demonstrated that major vascular complications and neurological events were more frequent with TAVI, while major bleeding and new onset atrial fibrillation were more frequent with aortic valve replacement. Symptom improvement as measured by the New York Heart Association (NYHA) class and six-minute walk distance favoured TAVI at 30 days and was similar to aortic valve replacement at one year.
The PARTNER trial is the first randomised, controlled trial of a transcatheter aortic valve. Cohort A of the trial studied 699 elderly patients with severe, symptomatic aortic stenosis deemed at high risk for traditional open-heart surgery. The median age was 84.1 years. Patients were evaluated by a multidisciplinary team and were evenly randomised to receive either the Sapien valve with transfemoral or transapical delivery or traditional open heart surgery.
Edwards expects to submit the data from Cohort A of the PARTNER trial to the FDA in the second quarter. Results from the inoperable Cohort B of the trial also met the primary endpoints and were published in The New England Journal of Medicine. These data are currently under review by the FDA. Edwards continues to anticipate approval from FDA later this year for the treatment of inoperable patients.
“Recommendations to individual patients will need to weigh the appeal of avoiding open-heart surgery, with its known risks, against less invasive TAVI with different and less well understood risks, as well as the absence of long term follow-up. Future trials will help delineate the role of TAVI in intermediate risk patients,” Smith said.
