New Options for Worn-Out Heart Valves?>

New Options for Worn-Out Heart Valves

by Peter Jaret

Rock ’n’ roll may live forever, as fans of the genre like to say. But some of the greatest stars of rock are well into their 70s and showing signs of wear and tear. In April 2019, the Rolling Stones announced that the band was canceling a run of performances after lead singer Mick Jagger was diagnosed with a serious heart valve condition called aortic valve stenosis.

The famously high-energy 75-year-old was lucky. In the past, surgeons had to perform open-heart surgery to replace a worn-out valve like his, cutting open the chest by splitting the sternum (breastbone) and putting the patient on a heart-lung machine during the procedure. But in recent years, cardiologists have developed a new procedure, called transcatheter aortic valve replacement (TAVR), which involves threading a replacement valve through a major artery and positioning it inside the heart.

TAVR is far less invasive, poses fewer risks, and has a much faster recovery time than conventional surgery. Indeed, just a few days after the Rolling Stones announced they were postponing their tour, Jagger was tweeting his millions of fans after undergoing TAVR: “Thank you everyone for all your messages of support. I’m feeling much better now and on the mend—and also a huge thank you to all the hospital staff for doing a superb job.”

Even as they cheered Jagger’s swift recovery, aging rock fans probably had questions of their own. How common are heart valve problems? Am I at risk? If I develop heart valve problems, should I consider TAVR?

The aging heart

The human heart has four valves. These flaps of tissue open to allow blood to flow forward and close to prevent it from flowing backward. With age, valves can become stiff or scarred, causing heart valve disease. As life expectancy has increased over the past century, the prevalence of heart valve disease has steadily risen. More than one in eight people 75 and older have moderate or severe valve disease.

Aortic valve stenosis is one of the most common—and most serious—valvular problems, typically affecting people over age 65. Calcium deposits can accumulate in the valve and narrow its opening. The condition restricts blood flow, forcing the heart to work harder to pump blood into the aorta, which is the body’s main artery. Age is the biggest risk factor for aortic stenosis. Every 10-year increase in age is associated with a doubling of risk. Men are twice as likely as women to develop aortic stenosis. Smoking and untreated high blood pressure increase risk.

At first, aortic stenosis may not have noticeable symptoms, and many people have no symptoms until the disease is advanced. As the disease worsens and blood flow becomes more restricted, the following symptoms may appear, especially upon exertion:

  • Shortness of breath
  • Heart palpitations
  • Chest discomfort
  • Weakness or fatigue

More severe aortic stenosis can produce chest pain or tightness, dizziness or fainting, and heart failure, which can occur when the heart can’t pump enough blood to meet the needs of the body. It’s essential to report any symptoms promptly to your doctor because aortic stenosis can progress rapidly. In fact, roughly half of older patients with severe symptomatic aortic stenosis who don’t undergo surgery die of the disease within two years.

Can You Prevent Aortic Stenosis?

Coronary heart disease is known to increase the likelihood of valve disease, so it stands to reason that by taking steps to lower your heart disease risk, you could be reducing your risk of aortic stenosis as well.

Stenosis, diagnosis, prognosis

Doctors often first detect a valve problem when they notice a heart murmur while listening through a stethoscope. Mild, symptomless aortic stenosis may not require immediate treatment, but patients must be carefully monitored. Valve replacement may be recommended in selected patients with severe aortic stenosis who don’t have symptoms to prevent stenosis from worsening and to reduce risk of heart failure and sudden death.

The development of replacement heart valves and less-invasive procedures to implant them into the heart has dramatically improved the prognosis for people with aortic stenosis. Recent studies have shown that patients successfully treated for valve disease may end up living just as long and having the same level of function and quality of life as people in the general population.

Replacement valves are either biological (made from the tissues of an animal, such as a pig or a cow) or mechanical (manmade, usually from carbon or titanium). Manufactured mechanical valves are more durable than biological valves, but they require lifelong treatment with an anticoagulant like warfarin (Coumadin) to prevent blood clots from forming. Biological replacement valves typically last only 10 to 12 years but don’t require long-term anticoagulation. The TAVR procedure is performed with only biological replacement valves.

SAVR vs. TAVR

Since aortic stenosis is a mechanical problem caused by a defective valve, medications usually don’t help. The only proven therapy to improve symptoms is valve replacement. Surgical aortic valve replacement (SAVR), which involves opening up the chest and inserting a replacement valve into the heart, has been performed for decades. Unfortunately, advanced age, certain kinds of prior surgery, coexisting medical problems, or anatomical heart abnormalities can make open-heart surgery too risky to perform. TAVR reduces such risk.

To perform the TAVR procedure, cardiologists insert a catheter (a thin, flexible tube) into an artery, typically in the groin area. The catheter guides a collapsible replacement valve into the damaged valve. Once there, the new valve is expanded, and it pushes the old valve out of the way. The tissue in the replacement valve then takes over the job of regulating blood flow. The entire procedure takes about two to four hours.

When TAVR was first developed, it was recommended only for high-risk patients—that is, those who were too frail or sick to undergo surgery. But increasingly, cardiologists are using TAVR for patients at intermediate risk. Several randomized controlled studies have shown that the procedure is safer and poses less risk of complications than SAVR. Joint guidelines from the American College of Cardiology and the American Heart Association recommend TAVR for patients with symptoms of aortic stenosis who are at high risk and as a reasonable alternative to SAVR for symptomatic patients at intermediate surgical risk.

Some experts recommend TAVR for patients at low surgical risk even though the evidence is limited. Their view is largely based on two clinical trials in which patients who underwent TAVR had outcomes that were similar or better than those who underwent SAVR. In one trial, 1,400 patients with aortic stenosis and at low surgical risk were randomly assigned to TAVR or SAVR. The TAVR group had a lower risk of complications at 30 days and of being hospitalized or suffering a disabling stroke after one year.

Another Heart-Valve Problem: Mitral Valve Regurgitation

The aortic valve is the valve most likely to cause problems as we get older. But another valve, the mitral valve, can also cause trouble, and in some cases even require replacement.

Balancing risks and benefits

TAVR isn’t an option for everyone with aortic stenosis. The procedure isn’t recommended for people who have:

  • Other medical conditions that could prohibit sufficient benefit from TAVR
  • Other valve conditions that can only be treated surgically
  • Anatomical issues that make TAVR risky, including an aortic valve that’s too small to accommodate a replacement valve
  • Active endocarditis (inflammation of the inside lining of the heart)
  • A life expectancy of one year or less

Like any medical procedure, TAVR poses its own risks, which can include bleeding and stroke, as well as complications from anesthesia. Nearly 25 percent of patients who undergo TAVR—as with SAVR—will need to have a pacemaker implanted to regulate their heartbeat.

It’s worth noting that TAVR is new enough that researchers don’t yet know much about its long-term effectiveness beyond five years. Studies currently underway are testing the effectiveness of TAVR in intermediate-risk patients who will be followed for 10 years with annual echocardiograms to assess how the artificial valve is performing.

Although TAVR is far less invasive than surgical implantation and has fewer risks, it’s still a complex procedure. Full recovery typically takes four to eight weeks. The outlook for most older patients is excellent, with a significant improvement in quality of life.

As for the world’s most famous TAVR patient, within a month of having his procedure, Mick Jagger posted a video that showed him going through his high-energy stage routine—alive and well and ready to perform again.

This article first appeared in the August 2019 issue of UC Berkeley Health After 50.

Also see A New Device to Ease Heart Failure Symptoms.