5 advances in heart health that are saving lives

By Patrick Boyle, Senior Staff Writer

Feb. 13, 2024

A heart valve made from animal tissue gets delivered through a catheter from a patient’s groin to their heart, replacing the patient’s own faulty valve. A class of drugs designed to reduce diabetes is found to reduce cardiac failure as well. A medication that mimics a hormone instructs the body to carry out biological functions that protect the heart.

These are just some of the recent innovations in cardiac care that are saving countless lives. 

“The number of [advances] that have happened in the last 20 years is just extraordinary,” says Steven E. Nissen, MD, chief academic officer of the Heart, Vascular, and Thoracic Institute at the Cleveland Clinic in Ohio. “[Some] are game changers with a huge public health impact.”

Here are five advances that doctors and researchers tout as having a significant impact on patient lives.

Transcatheter aortic valve replacement

Aortic valve stenosis (AVS) occurs when the opening of the aortic valve (through which blood passes from the main pumping chamber, the left ventricle, to the aorta and out to the body) is narrowed, reducing blood flow from the heart to the aorta. It can cause chest pain, fainting, and fatal heart failure. Each year, as many as 300,000 people in the United States are diagnosed with AVS, according to the Frankel Cardiovascular Center at University of Michigan Health.

For many years, the treatment for the most severe cases was open-heart surgery to repair or replace the damaged valve. Because the disease often develops as people grow into old age, many of those patients are not good candidates for such major surgery because of the risks of complications.

Transcatheter aortic valve replacement (TAVR) provides a minimally invasive alternative to major surgery by delivering a replacement valve into the heart through a catheter. The doctors make a small incision in the groin or chest, insert the catheter into an artery, and with the help of imaging technology such as X-rays, guide the replacement valve through the artery to the site of the damaged valve. The replacement valve (often made of cow or pig heart tissue) is compressed in the catheter and expands into place after delivery. (The American Heart Association provides a full explanation with illustrations.)

French cardiologist Alain Cribier, MD, is credited with performing the first successful TAVR, in 2002, in France, according to the American College of Cardiology. The U.S. Food and Drug Administration (FDA) first approved the procedure in 2011 for certain patients at the highest risk from major surgery.

Subsequent studies showed that TAVR was at least as effective and sometimes superior in low-risk patients with severe AVS. The procedure was studied and improved through various trials, most notably the PARTNER (Placement of Aortic Transcatheter Valves) trials, conducted at numerous academic medical institutions, which prompted the FDA to gradually expand its approved use for all patients with severe cases of the disease. The treatment is now commonly used in lieu of open-heart surgery.

SGLT2 inhibitors

In the early 2000s, clinical trials demonstrated the power of a class of drugs to lower blood sugar in patients with type 2 diabetes. The drugs inhibit the ability of a protein (SGLT2) to make the body reabsorb glucose into the kidneys — which, in people with diabetes, drives their glucose levels too high. Over time, doctors and researchers found that the drugs, called SGLT2 inhibitors, also provided protections against heart failure and the worsening of kidney disease by lowering blood pressure, reducing plasma volume (which reduces the workload on the heart), and lowering sympathetic nervous system activity.

Academic medical centers have played key roles in developing, refining, and studying SGLT2 inhibitors. A meta-analysis of five randomized controlled trials, published in The Lancet in 2022, found that the inhibitors “significantly reduce the risk of mortality and worsening heart failure and improve patient symptoms and overall health status when added to standard therapy for heart failure.” The study was conducted by researchers at Harvard Medical School in Massachusetts, Yale School of Medicine in Connecticut, Duke University Medical Center in North Carolina, and the Northwestern University Feinberg School of Medicine in Illinois, among others.

The FDA first approved the first SGLT2 inhibitor (canagliflozin) to treat type 2 diabetes in 2013, and since 2020 has approved three other SGLT2 inhibitors (dapagliflozin, empagliflozin, and sotagliflozin) to lower the risk of heart failure, heart attacks, and cardiovascular death in patients with diabetes.

Mitral valve clips

In mitral regurgitation, the flaps of the mitral valve, which controls the flow of blood from the left atrium to the left ventricle, do not close properly. This can cause blood to leak back into the heart in the wrong direction. While many people do not feel symptoms for years, as the condition progresses it often causes escalating health problems, including shortness of breath, swelling of hands and feet, symptoms of shock (such as loss of consciousness), atrial fibrillation, and heart failure.

Mitral regurgitation affects an estimated 1.7% of the U.S. population, with the prevalence rising to about 9.3% in those over age 75, according to the Journal of the American Heart Association.

For many years, people with severe cases of mitral regurgitation had to decide whether to risk open-heart surgery to repair or replace the valve, or live with a defect that might kill them. MitraClip provides a less invasive option. Doctors guide a catheter through a vein in the patient’s leg to reach the heart. Through the catheter they deliver a small clip — made of cobalt-chromium with a polyester cover — that attaches to the valve to help it close more completely, as explained by Penn Medicine. The procedure takes 1-3 hours.

“You can put a clip on the mitral valve and reduce the amount of leakage substantially for people that are just too ill to be able to undergo surgery,” Nissen says. “That’s a pretty big innovation.”

Studies, such as one published last year in The New England Journal of Medicine, have shown that the clip reduces mitral regurgitation, the risk of hospitalization, and the risk of death for up to five years after the procedure. The study was conducted by researchers at numerous universities, including the Icahn School of Medicine in New York, the Cleveland Clinic, and the University of Colorado Hospital.

Development of MitraClip began in the late 1990s at Evalve Inc. (later purchased by Abbott), with the first implant in a patient occurring in 2003, according to Abbott. The FDA initially approved the procedure for certain severely ill patients in 2013, and gradually expanded approvals for more patients.

GLP-1 agonists

Drugs such as Ozempic and Wegovy, which are widely used to treat diabetes and obesity, have recently been found to reduce heart attack and stroke. 

The drugs mimic the intestinal hormone (GLP-1) that (as explained here) triggers the release of insulin (which lowers glucose levels), keeping blood sugar down, slowing digestion, and increasing how full a person feels after eating.

The FDA approved the GLP-1 agonist Ozempic as a treatment for diabetes in 2017. The agency approved Wegovy for weight loss in 2021, and approved Mounjaro (for diabetes) and Zepbound (for weight loss) in 2023.

Studies have shown that patients who took the drugs for diabetes also experienced significant reductions in adverse cardiac events, according to a review published in 2023 in Frontiers in Clinical Diabetes in Healthcare. Research at the University of Texas Southwestern Medical Center has included the effect of GLP-1 agonists on glucose control and weight loss, while research at the University of Vermont Medical Center has included cardiovascular outcomes.

“The GLP-1 drugs are being widely used for treatment of diabetes, and they have been shown in treatment of patients with diabetes to reduce the risk of cardiovascular morbidity and mortality,” Nissen notes.

In addition to reducing such cardiovascular risk factors as glucose levels, weight, lipid levels, and hypertension, the drugs also stimulate production of nitric oxide (which expands blood vessels and increases blood flow), reduce oxidative stress (thus stabilizing antioxidant levels), and help to reduce inflammation.

Helping babies with congenital heart defects live longer

About 40,000 U.S. babies are born with congenital heart defects (CHDs) each year, making CHDs the leading cause of infant illness and death associated with birth defects, according to the Centers for Disease Control and Prevention (CDC).

In decades past, babies born with a severe CHD almost always died in childhood, often before their first birthdays. Those with less severe cases routinely died by early adulthood. But various medical advances have gradually and significantly prolonged their lifespans. According to the CDC:

• 69% of babies born with critical CHDs are expected to survive to at least 18 years of age
• 95% of those born with non-critical CHDs are expected to survive until at least age 18
• 81% of babies born with any type of CHD are expected to survive to at least age 35; with more and more of those babies living into old age

Because so many babies with CHDs are now living longer, “the prevalence of patients with CHD has shifted away from infancy and childhood towards adulthood,” as reported in a 2019 literature review in Acta Paediatrica (a journal from the Karolinska Institutet in Sweden). In 2010 (the last year for which a full analysis is available), about 1 million children and 1.4 million adults in the United States were living with CHDs, according to the CDC.

Researchers and doctors attribute the shift to numerous improvements in cardiovascular diagnosis and treatment that began decades ago, and that continued improving and growing more common. They include:

• Earlier and better detection through such methods as fetal echocardiography (which evaluates the heart in utero), pulse oximetry screening of neonates before they leave the hospital, and diagnostic techniques for babies, such as echocardiography and magnetic resonance imaging (MRI).
• Advances in surgical interventions, such as septostomy to initiate (in utero) treatment for cyanotic heart disease, which reduces the amount of oxygen delivered to the body; and a series of surgeries in the years after birth to correct one of the most fatal CHDs: hypoplastic left heart syndrome, which is an underdevelopment of the left side of the heart that reduces its ability to pump blood.

The increased survival of children with CHDs has created a growing need for physicians trained to treat them when they become adults — a need that is expected to rise as the country’s population ages. In 2012, the American Board of Medical Specialties created a subspeciality certification for adult congenital heart disease.

These are just some of the many innovations in cardiac care that have saved countless lives.

“The recent advances in the diagnosis and treatment of cardiac and related disorders have not only improved the quality of care,” said David J. Skorton, MD, a cardiologist and president and CEO of the Association of American Medical Colleges. “They have also expanded life-saving care to more people by making procedures less invasive and less risky.”