Expanding Eligibility for Minimally Invasive Aortic Valve Study
Date: October 30, 2012
Interventional cardiologist Jon Resar and cardiac surgeon John Conte have witnessed the short-term benefit to many of their frail and elderly patients of having a minimally invasive procedure to replace the aortic valve. They are co-investigators in the national trial to evaluate Core-Valve, which began in 2011. Now, the trial is entering an expanded phase, broadening the eligibility of patients.
The first phase of testing involved about 800 patients nationwide with severe, symptomatic aortic stenosis who were at extreme risk—and therefore not candidates for open surgery. Meanwhile, those at very high risk were randomized to have either the transcatheter aortic valve replacement (TAVR) or traditional open heart surgery to implant a new valve.
“Recovery is quicker with the TAVR approach compared to open surgery,” says Resar. “Patients have almost immediate relief from their symptoms, such as shortness of breath and fatigue, and are walking the next day.”
To determine eligibility, patients are evaluated on the STS scale to assess their operative risk for standard open-heart valve replacement surgery. Those with a score below 4 percent, which accounts for about 75 percent of patients who need the surgery, do not face the high risk of complications with standard surgery and have not so far been offered the CoreValve.
In the new, broadened phase of study, patients with an STS score between 4 percent and 10 percent will be eligible to be randomized in the trial. The primary endpoint will be to compare the TAVR and surgery groups for all-cause mortality or stroke at two years.
“This is a very important subgroup of patients to look at,” says Resar. “They often have a difficult recovery from conventional valve replacement surgery and are looking for a less invasive approach.”
Charlotte Scheufele, a 77-year-old Maryland woman, suffered from severe congestive heart failure and diabetes when her aortic valve began to fail. “It was frightening,” she says. “I felt as though I couldn’t catch my breath.”
Because of comorbidities, Scheufele was eligible to have TAVR. However, her leg arteries were too small to pass the catheter to her heart—a roadblock faced by about 25 percent of patients eligible for CoreValve.
So, says Conte, “we deployed the CoreValve directly into her aorta with a mini-sternotomy, just as if we were going through the groin. The difference between this and a standard valve implantation is that the patient did not need to be on the heart-lung machine or have her heart stopped. There was no need to cut out her native valve.”
Resar calls that approach a game changer that will enable physicians to offer TAVR to many more patients who otherwise would not qualify because of narrowed limb arteries. Conte and Resar were one of the first teams to perform that procedure as part of the CoreValve trial, and they have employed the technique in eight of their 45 TAVR patients so far.
Asked about her recovery five months after the procedure, Scheufele says, “I’m feeling fine and can do things I hadn’t been able to do for a long time. I vacuum, wash clothes, cook. People can’t believe that I recovered so well.”
The Hopkins team also offers the Edwards Sapien valve, which is now FDA-approved for patients who, by the assessment of two cardiac surgeons, are not deemed to be candidates for surgical aortic valve replacement.
“Despite our tremendous early success, we need to proceed cautiously,” says Conte, “because of a lack of long-term data. However, in appropriately selected patients, it can be lifesaving. It offers high-risk surgical patients, many of whom are elderly, a new chance to enjoy their golden years.”