FORT LAUDERDALE, FLA. — Transcatheter insertion of a stented aortic valve through the left ventricular apex is possible for patients with critical valvular aortic stenosis, according to a multicenter study.
Feasibility is based on a total of 36 procedures at three institutions. Valve recipients were high risk because they were aged older than 70 years, had significant comorbidities, and/or had a Society of Thoracic Surgeons Predicted Risk of Mortality score of 15% or more.” Dr. Lars G. Svensson said at the annual meeting of the Society of Thoracic Surgeons.
Dr. Svensson and his associates conducted the FDA-approved study to assess feasibility of less invasive transcatheter delivery for such high-risk patients. Without surgery, 1-year survival is an estimated 30%. Also, 30%-60% of people with critical valvular aortic stenosis do not receive treatment, according to registry data.
The study is a new arm of PARTNER, an ongoing, randomized assessment of retrograde transfemoral arterial delivery of the same device, the Sapien THV Valve (Edwards Lifesciences). The investigational device is a balloon-expandable stainless steel stent with an internally mounted equine pericardial valve.
“This is pioneering work in a high-risk group of patients with a very challenging procedure,” said Dr. Thomas A. Vassiliades, study discussant and surgeon in the division of cardiac surgery, Emory University, Atlanta.
Surgeons begin with a check for calcium that might obstruct device insertion. Then the valve is crimped down and placed inside a loader before transcatheter insertion. The most common entry point in the study was via the sixth intercostal space. After placement, there is rapid pacing for balloon inflation.
“Team cooperation is essential to success. A lot of cardiologists are also involved, and the procedure would not be as successful without them,” said Dr. Svensson, a thoracic surgeon at the Cleveland Clinic. Dr. Svensson serves on the executive committee board of Edwards Lifesciences but does not receive any financial compensation.
There was considerable hemodynamic and functional improvement, Dr. Svensson said. For example, a mean 1.6-cm
Comorbidities were a “big factor” in patient outcomes, Dr. Svensson said. For example, 50% had prior coronary bypass surgery and approximately one-third had porcelain aortas. There were four failed implants, for an overall implant success rate of 89%. Physicians converted these four failures to open procedures.
There were six deaths within 30 days for a 16.7% mortality rate. One patient died from multiple organ failure and the other cause of death was stroke 5 days postoperatively. There were four procedure-related deaths. “We realize these are [very ill patients] and it is a complicated procedure, but we need to know how many benefit by 6 months by having the device,” Dr. Vassiliades said. He had no financial disclosures, but his institution is participating in the transfemoral arm of the PARTNER study. At 6 months, survival was 59%, Dr. Svensson replied.
Dr. Vassiliades questioned a counterintuitive finding that outcomes were better in the first 20 patients. Dr. Svensson replied that some aspects of the procedure had to be relearned after a 6-month downtime.
After transapical insertion, a stent valve is positioned across the native aortic valve. Cleveland Clinic/Lars G. Svensson