The Sapien replacement heart valve made by Edwards Lifesciences (NYSE:EW) is a safe alternative for redoing cardiac surgery and lowers all-cause mortality for diabetics at high risk for aortic valve surgery, according to 2 data sets presented at the European Society of Cardiology congress in Amsterdam.
A Dutch study of 16 patients, who received a minimally invasive Sapien transcatheter aortic valve implant after their bioprosthetic heart valves failed, showed that survival rates for patients who receive the device match that of those who are re-operated with a riskier redo cardiac surgery, according to an ESC press release.
"We have shown for the first time that the long term survival of high risk patients with failing bioprostheses treated with transcatheter valve-in-valve implantation is comparable to high-risk patients treated with redo cardiac surgery," Dr. Spyridon Katsanos of Leiden University Medical Center in the Netherlands said in a press release.
Bioprosthetic heart valves are being used more often to treat older patients with comorbidities, up from 18% in 1991 to 59% in 2003, because mechanical prostheses carry an increased risk of bleeding complications due to patients’ lifelong need to take anticoagulants along with them, Katsanos noted.
But bioprosthetic heart valves can fail due to structural valve deterioration, he pointed out. At 11-13 years of follow-up in registries of more than 300,000 patients undergoing aortic valve replacement, 3.1% of patients who got a bioprosthesis needed redo surgery, compared with 2.3% of patients who received an aortic mechanical prosthesis.
"Transcatheter valve-in-valve implantation is a minimally invasive procedure performed through transfemoral or transapical approach under fluoroscopic guidance and does not require sternotomy and cardiopulmonary bypass,” Katsanos said. “Elderly patients deemed not operable and also high risk patients with failing bioprostheses may have a treatment alternative to redo cardiac surgery."
Diabetics may be safer with TAVI than surgical aortic valve replacement
Separately, new post-hoc data analysis from Edwards’ Partner trial for Sapien showed that high surgical risk diabetics with aortic stenosis experienced a 35% lower all-cause death rate 1 year after treatment with TAVI, compared to those treated with surgical aortic valve replacement.
Partner, the 1st randomized, controlled trial of a TAVI device in the U.S., included 657 patients with severe, symptomatic aortic stenosis deemed at high risk for traditional open-heart surgery.
A previous Partner analysis showed TAVI beat traditional aortic valve replacement surgery only when conducted transfemorally, but not via transapical access.
The new post-hoc analysis looked at the 275 Partner patients who were diabetic. In the diabetic group, 145 patients were treated with TAVI, with 130 treated surgically.
Of the deaths in the diabetic group, 1-year all-cause mortality was 18% for patients treated with Edwards Sapien valve delivered via the femoral artery or a small incision between the ribs, and 27.4% for patients treated with surgical aortic valve replacement.
The new data also showed that diabetics treated with TAVI experienced faster quality of life improvement and lower 1-year rates of renal failure than those treated with surgery.
The post-hoc analysis did not account for diabetic medications, severity or duration of diabetes, microvascular complications or glucose control, researchers noted, and further studies to understand how insulin treatment or the presence of metabolic syndrome may influence outcomes are needed.
"While this was not a pre-specified analysis of the trial and should be considered hypothesis-generating, our study raises the possibility that TAVI may be the preferred approach for diabetic patients with severe symptomatic aortic stenosis who are at high surgical risk," Partner trial clinical investigator Dr. Brian Lindman said in a press release.
Edwards has a solo hold on the U.S. market for TAVI systems. Sapien gained FDA approval in November 2011 for the treatment of inoperable patients, and expanded the indication to high-risk surgical patients in October 2012.
The company’s next-generation Sapien XT recently became the 1st transcatheter aortic valve implant to hit the market in Japan and is available in the U.S. as part of an 500-patient trial, which Edwards is ramping up after winning investigational device exemption from the FDA.
In addition, Edwards holds a strong corner in the European TAVI market after recently winning a long patent battle in Germany with rival TAVI maker Medtronic (NYSE:MDT) and its CoreValve device.