There was big news on Twitter this spring. The Rolling Stones tweeted that Mick Jagger, who is 75 and had been diagnosed with a heart problem, underwent a procedure and was expected to be back on the stage as soon as possible. His timing was spot on. Jagger had been diagnosed with aortic stenosis, a narrowing of his aortic valve. This was not long after two studies showed TAVR, a revolutionary catheter treatment, has important advantages over open heart surgery in people who are healthier and at least a decade younger than the people who typically have the procedure, who tend to be in their 80s.
Open heart surgery has been widely available since the 1960’s. However, it is invasive, and generally entails opening the chest and using the heart-lung machine to repair or replace the valve. The far less invasive TAVR procedure means patients spend fewer days in the hospital and are able to return to their normal lives far more quickly.
It has been a banner year for TAVR, or transcatheter aortic valve replacement, and not only because of the big celebrity spotlight. For people with severe narrowing of the aortic valve, TAVR surgery involves threading a catheter (a hollow tube) into the groin and up through an artery to the appropriate location in the heart. The old valve is left in place. Two landmark TAVR studies published in The New England Journal of Medicine (NEJM) in March found that disabling strokes and rehospitalizations, which can be complications of treatment, were at least slightly lower with TAVR than with open heart surgery, known as surgical aortic valve replacement (SAVR). The average age in the studies was low 70s.
Many cardiologists and cardiac surgeons believe these studies will change the standard of care for patients with aortic stenosis. At present, TAVR is FDA-approved only for patients who are considered to be at intermediate- or high-risk for complications with open heart surgery. Often these people are very sick, and many have congestive heart failure. If the FDA approves the procedure for low-risk patients, tens of thousands of patients across the country may be able to undergo a less invasive approach to replace their aortic valve and avoid open heart surgery.
“It’s been a steady climb,” says Yale Medicine cardiologist John Forrest, MD, director of the Structural Heart and Valve Disease Program, part of the Yale New Haven Health System (YNHHS) Heart and Vascular Center. An expert on TAVR and investigator in one of the two NEJM studies (as well as many other studies of TAVR over the years), he expects Yale Medicine to do 300 of the procedures this year at Bridgeport and Yale New Haven hospitals. (He is currently treating low-risk patients through a continued access study, which provides eligible patients access to a drug or product before FDA approval.)
A new choice for Baby Boomers
If you are, say, 30 years old, chances are you’ve never heard of aortic stenosis or TAVR. But in people older than 65, the aortic valve is the most common heart valve to require replacement when calcium buildup or scarring causes it to become narrow, which can affect blood flow. Dr. Forrest notes that the condition will become even more common as Baby Boomers (and the population overall) age.
“Unfortunately, there is no way to prevent aortic stenosis,” Dr. Forrest says. “You can think about it like arthritis,” he explains. “We all tend to get a little bit of arthritis, but we tend to be OK into our 50s and 60s unless there is an injury or something that is inherently wrong with our joints. But when we get into our 70s or 80s, we start to have more serious issues.” The aortic valve is like a joint that people use every day of their lives, he says. “It opens and closes every time your heart beats, and it just tends to wear out.”
Someone with aortic stenosis may notice such symptoms as fatigue, shortness of breath, or chest pain (although some people have no symptoms at all). A doctor listening to their heart through a stethoscope may hear a sound known as a heart murmur, which could be a sign that stenosis is inhibiting adequate blood flow.
Research is still pushing TAVR forward
Heart surgeons and cardiologists have been using transcatheter therapies for several years to care for patients with valvular heart disease who would not have been able to tolerate traditional open heart surgery, says cardiac surgeon Abeel A. Mangi, MD, MBA, surgical director of the Structural Heart and Valve Program. These include very elderly patients, those who have had many prior heart operations, and those with certain conditions, he says. “TAVR has been proven to help patients like these live longer,” Dr. Mangi says. “Now we are entering an era where transcatheter valve technologies may become available to most patients with heart valve disease. This is an exciting time to be a heart valve surgeon because we have so many more tools at our disposal—be it open heart surgery, or TAVR—and we can tailor the treatments we offer patients to their medical conditions.”
In fact, Yale Medicine cardiologists have been at the forefront of TAVR research in general since the procedure became available in the mid-2000s. In addition to Dr. Mangi’s and Dr. Forrest’s research, Alexandra Lansky, MD, a Yale Medicine cardiologist who has studied catheter-based procedures from the beginning of her 20-year career, is working on research to prevent stroke among TAVR patients. While the risk of stroke is lower with TAVR than it is with surgery, it still affects 3 percent of TAVR patients, Dr. Lansky says. She is in the early stages of developing a device that would use fine mesh netting to seal off blood flow to the brain.
“It’s been a steady push forward,” Dr. Forrest says. “With each new finding, we continue to see that TAVR may be a better option than surgery for patients. If you analyze the lower risk patients in these two new studies, you would see that they do even better than older patients.”
Meanwhile, there are still some patients who will need to have open heart surgery for aortic stenosis, because their anatomy makes TAVR difficult, they need additional procedures, or they have infections of the heart valves. While there is no medical procedure that is without risk, there is no safer open heart operation than the aortic valve replacement, says Dr. Mangi. “Surgery is still a very good procedure. It results in very good outcomes,” Dr. Forrest says.
Feature courtesy of Yale Medicine