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Every year, researchers gain a deeper understanding of the pathways that lead to cardiovascular disease. Along with continuously evolving technological and therapeutic advances, this opens new avenues to prevent and treat heart disease and stroke.

As a leading funder in heart- and stroke-related research, the ·¬ÇÑÊÓƵ compiles an annual review of significant scientific advances in the fight against cardiovascular disease, which claims more than 850,000 lives in the U.S. each year and is the leading cause of death and disability worldwide.

In 2024, several notable strides were made in the ability to assess cardiovascular risk, identifying predictors of disease much earlier in life that offer greater opportunities for prevention. The pressing need for prevention was driven home by research revealing a shift in national health trends, as cardiovascular disease burdens that had been falling reversed course and began an upward climb – a disturbing trend researchers forecast to continue in the coming decades.

Investigators also made major strides in developing strategies to reduce heart failure-related events and deaths, explored new therapies for bleeding strokes, found wide-ranging benefits for anti-obesity drugs and ways to lower the life-threatening risks of cardiogenic shock.

Here are some of the most significant developments from 2024.

Forecasting the burden of CVD

Cardiovascular diseases – including coronary heart disease, heart failure, atrial fibrillation and stroke – are the most common causes of death in the U.S. After decades of reducing CVD and stroke-associated death and disease, that trend has reversed course and prevalence has begun rising again in recent years.

According to extensive research that led to a new AHA , the prevalence of cardiovascular disease and many of its risk factors is expected to continue to climb over the next 30 years. By 2050, cardiovascular disease is expected to increase from 11.3% to 15% of the population, affecting up to 45 million U.S. adults. Stroke prevalence is expected to double, from 10 million to almost 20 million adults. Obesity – a major risk factor for cardiovascular disease – is predicted to climb from 43% of the population to more than 60%. These findings serve as a call to arms and a warning that we must better control risk factors to avoid the oncoming tsunami of cardiometabolic disease.

Treating cardiovascular disease can be extremely costly. In 2020, 1 in 3 U.S. adults received care for a cardiovascular risk factor or condition. In a second AHA Presidential Advisory, researchers warned the associated economic burden would also continue to rise in the U.S. in the coming decades. This in-depth research projected health care costs for cardiovascular risk factors would triple by 2050 from their 2020 levels, from $400 billion to $1.344 trillion.

Predicting – and preventing – future cardiovascular disease

A growing number of studies focus on ways to predict who is at risk for future cardiovascular disease so that more targeted efforts may be made to prevent it.

One study looked for ways to identify people at risk for cardiovascular disease because of the way their blood platelets behave.

Research has shown that hyperactive blood platelets are more prone to clumping together to form potentially deadly blood clots in the arteries, a condition known as atherothrombosis. This can lead to heart attacks and strokes.

Researchers have long known about this condition, but identifying who might be at risk for platelet hyperactivity has been challenging. Now genetic research has provided a way forward. Investigators looked for genetic differences among people with peripheral artery disease, or PAD, whose platelets were hyperactive and compared them to the genes of healthy people.

After sifting through hundreds of genes, they developed , the Platelet Reactivity ExpreSsion Score – a tool that assesses platelet reactivity using genetic signatures. A study that validated the tool found it could be useful in identifying people who could benefit from antiplatelet therapy to lower their risk for future cardiovascular events.

Three new studies suggest cholesterol, hypertension and sedentary behavior – all major cardiovascular risk factors for adults – may begin doing damage as early as childhood.

High cholesterol is a major risk factor for atherosclerosis, the buildup of plaque in the arteries that can lead to heart attacks and strokes. Prior research has shown the risk for these cardiovascular events rises along with cumulative lifetime exposure to low-density lipoprotein cholesterol, or LDL, the so-called "bad" cholesterol. Other studies have found fluctuations in LDL are linked to worse cardiovascular outcomes, but why exposure to cholesterol causes the development of inflammatory plaque is not well understood.

Researchers may have found clues through a study in which mice were fed a high-cholesterol, Western diet – either intermittently, causing cholesterol to rise and fall, or continuously but starting later. Among mice that were fed the diet intermittently and earlier, researchers noted changes in the number and type of arterial macrophage, or white blood cells that play a critical role in atherosclerosis. These mice also experienced an acceleration of plaque growth.

The same researchers then analyzed data from the Young Finns Study, one of the largest long-term studies of cardiovascular risk from childhood to adulthood. They found a link between exposure to cholesterol early in life and plaque size in mid-adulthood in humans. Taken together, they concluded these show early, intermittent exposure to cholesterol may be a strong predictor of accelerated plaque growth, suggesting high cholesterol early in life may be even more damaging than cholesterol that doesn't rise until later adulthood.

Likewise, evidence is mounting that hypertension, or high blood pressure, that develops in childhood is a strong predictor of poor cardiovascular health in adulthood. Childhood hypertension is on the rise, affecting roughly 1 in 25 U.S. youth ages 12 to 19.

Researchers compared long-term health data for 26,605 Canadian children who had been diagnosed with hypertension to 128,025 of their peers who had not. Up to 20 years later, children who had been diagnosed with high blood pressure faced more than twice the risk for a major adverse cardiovascular event, or MACE, including stroke, hospitalization for a heart attack or unstable angina, coronary intervention or congestive heart failure.

Sedentary behavior is another major cardiovascular risk factor and a growing problem among children worldwide, who spend an average of 8 to 10 hours per day in prolonged inactivity. This of the Avon Longitudinal Study of Parents and Children in the UK investigated the impact of sedentary time, light intensity physical activity, and moderate to vigorous physical activity on cardiac structure and function for 1,682 children over 13 years.

They found that the longer children were sedentary, the bigger the increase in cardiac size. Overall, sedentary time contributed to an increase in body fat, inflammation, blood pressure, cholesterol, arterial stiffness and subsequent cardiac enlargement, raising the risk for cardiovascular problems later in life. Reducing sedentary behavior by engaging in light physical activity at least three hours a day lessened these impacts.

A new tool to help calculate cardiovascular risk

The PREVENT risk calculator is a new tool developed by volunteer science experts working with the ·¬ÇÑÊÓƵ to help people better understand their risk for developing heart disease, stroke or heart failure. It calculates 10- and 30-year total cardiovascular disease risk using heart, kidney and metabolic health measures such as cholesterol, blood pressure, blood glucose, weight and age. Unlike other risk calculators it does not factor in a person's race or sex but does include measures of social disadvantage.

The tool was using data from more than 6 million U.S. adults whose average age was 53 years old. Over an average 4.8 years of follow-up, PREVENT accurately and precisely predicted risk for cardiovascular disease and its many subtypes in a large, diverse and contemporary sample of U.S. adults.

A study using NHANES data investigated how well PREVENT estimated cardiovascular risk compared to the Pooled Cohort Equation, or PCE, which was the previous standard for calculating 10-year cardiovascular risk. The PREVENT calculator predicted lower estimates for atherosclerotic cardiovascular disease risks than the PCE, suggesting prior estimates may have been too high and some people may have been overtreated with medications to lower lipids and blood pressure.

Growing evidence of the wide-ranging benefits of anti-obesity drugs

According to the Centers for Disease Control and Prevention, 40% of U.S. adults are obese, a problem that has been steadily growing over the past decade. Obesity contributes to cardiovascular disease and other chronic illnesses, accounting for an estimated 4 million deaths globally in 2015.

A growing body of evidence finds anti-obesity drugs developed to treat diabetes can have wide-ranging benefits for people with and without diabetes, reducing cardiovascular, kidney and heart failure-related symptoms and deaths and improving weight loss in adults and children. Five such studies were published in the New England Journal of Medicine.

Three studies investigated potential uses for semaglutide, a glucagon-like peptide-1 receptor agonist, which has previously been shown to reduce cardiovascular risks in people with diabetes. But it was unknown whether the drug could reduce these risks in people who didn't have diabetes. A multi-center, double-blind, randomized, placebo-controlled, event-driven of 17,604 middle-aged adults found that it could.

People who are dealing with obesity or being overweight – with pre-existing cardiovascular disease but no diabetes – who were injected with 2.4 mg of semaglutide on a weekly basis lowered their risk for cardiovascular-related death, nonfatal heart attacks and nonfatal strokes over more than three years of follow-up.

Another found people with obesity-related heart failure with preserved ejection fraction and type 2 diabetes could reduce their heart failure symptoms and achieve greater weight loss with the same once-weekly dose. And a third study people with chronic kidney disease and type 2 diabetes could benefit from an even lower dose of semaglutide. Patients given 1 mg subcutaneously weekly over a median 3.4 years improved kidney function and reduced their risk of dying from all causes.

Tirzepatide, another glucagon-like, peptide-1 receptor agonist, similarly of cardiovascular-related deaths and worsening heart failure in obese people with heart failure and preserved ejection fraction when given in a 15 mg dose subcutaneously for 52 weeks.

New finds liraglutide, a third glucagon-like, peptide-1 receptor agonist that has been shown to induce weight loss in obese adults and adolescents, also can be used to improve weight loss in children under 12, when daily injections are added to lifestyle interventions. No medications have yet been approved to treat weight loss in children in this age group.

More advances in heart failure treatment and prevention

Heart failure occurs when the heart isn't able to properly pump blood to the rest of the body, depriving the tissues of oxygen. There are several types of heart failure, which can affect the left, right or both sides of the heart. When it affects the left chamber, or ventricle, the heart has to work harder to pump the same amount of blood. The percentage of blood volume ejected from the heart with each beat is measured by a unit called ejection fraction, or EF, which is considered normal when the left ventricle ejects about 60% of the blood that's in it.

In heart failure with preserved ejection fraction, or HFpEF, the heart can't fill well with blood during the resting period between heartbeats. Another type of heart failure is HFrEF, or heart failure with reduced ejection fraction, which occurs when the left ventricle loses its ability to properly contract. When this happens, the heart can't pump hard enough to push blood into the circulation.

Aldosterone antagonists, sometimes called mineralocorticoid receptor antagonists, have been shown to reduce symptoms and mortality in patients with HFrEF, but it was unknown how well a new class of therapies called non-steroidal mineralocorticoid receptor antagonists would work for people with mildly reduced or preserved ejection fraction.

In an international, double-blind, clinical , 6,001 patients with heart failure and left ventricular ejection fraction of 40% or greater were randomly assigned to receive the drug finerenone (at a maximum dose of 20 mg or 40 mg once daily) or matching placebo, in addition to usual therapy.

After a median 32 months of follow-up, patients who took finerenone had a significantly lower rate of worsening heart failure events and death from cardiovascular causes than those who took placebo. These findings could have potentially practice-changing implications.

Another study looked at ways to repair heart valves in people who have heart failure.

When the heart contracts, blood flows normally through the mitral valve into the left ventricle. Mitral regurgitation occurs when some blood leaks backward through the mitral valve into the left atrium during every contraction, creating increased pressure in the atrium from the excess blood volume.

The trial investigated whether a minimally invasive procedure to repair the mitral valve would improve outcomes in patients with heart failure and functional mitral valve regurgitation. More than 500 patients from 30 sites in nine countries were randomly assigned to transcatheter mitral valve repair with guideline-recommended medical therapy or medical therapy alone. The addition of transcatheter mitral valve repair resulted in lower rates of first or recurrent hospitalizations for heart failure or cardiovascular death, better health a year later and a lower rate of first or recurrent hospitalization for heart failure two years after the repair.

Another study in the ·¬ÇÑÊÓƵ journal looked at how heart failure develops by investigating the ways cells in the hearts of mice interact. Prior research has shown that different types of cells in the human heart respond differently to stress, which can change the way these cells interact. Most heart failure research has focused on cardiomyocytes, the cells that make up heart muscle. Researchers in this study looked at the role played by endothelial cells, which regulate the movement of materials in and out of the bloodstream. They found that when stressed, endothelial cells produce a protein called Igfbp7, which causes cardiac dysfunction. But a vaccine that targeted Igfbp7 improved cardiac function, suggesting vaccine therapy could be a promising treatment for preventing the development heart failure.

New management strategies for hypertrophic cardiomyopathy (HCM)

Hypertrophic cardiomyopathy, or HCM, occurs when the walls of the left ventricle are thicker than normal, which can make them stiff. This reduces the amount of blood taken into the heart chamber and pumped out to the body. It is most often caused by abnormal genes in the heart muscle but typically doesn't get diagnosed until middle age.

When the thickened part of the heart muscle blocks or reduces blood flow from the left chamber to the aorta, this is called obstructive hypertrophic cardiomyopathy. Symptoms include chest pain, shortness of breath, fatigue, fainting, dizziness, a rapid or irregular heartbeat, swelling in the ankles, feet or legs or in the neck veins.

Roughly two-thirds of people with HCM have the obstructive type, which is potentially lethal. It can be treated with medications or, when that fails, with one of two types of septal reduction therapy. Septal myectomy is a surgical procedure to remove excess heart muscle, allowing blood to empty from the chamber more easily. Alcohol septal ablation is a minimally invasive procedure in which alcohol is injected into a blood vessel of the septum, causing some of the heart muscle to die. This treatment has a shorter recovery period but a higher risk for complications, such as irregular heart rhythms.

An analysis of data from 13 high-volume HCM centers from the international SHARE (Sarcomeric Human Cardiomyopathy Registry) study provides the most robust and comprehensive long-term results to date for the two main interventions for this complex condition. This landmark looked at outcomes for 1,377 people who underwent surgical septal myectomy and 455 people who underwent catheter-based alcohol septal ablation. After 10 years of follow-up, it showed an 83% overall survival rate, relatively free from heart failure with only rare occurrences of ventricular arrhythmias. The highest rate of heart failure-related complications occurred in a subgroup of women who underwent alcohol septal ablation, though it was unclear why.

Another new treatment helps reduce symptoms in people with obstructive HCM. HCM makes it much harder for people to stay active because the body isn't getting the oxygen it needs.

In a , double-blind trial, patients with symptomatic HCM, who were an average 59 years old, were randomly assigned to receive the drug aficamten or placebo for 24 weeks. People who took aficamten achieved greater improvements in peak oxygen uptake than those taking placebo.

Lowering the life-threatening risks of cardiogenic shock

Cardiogenic shock is a life-threatening condition that occurs when the heart can't pump enough blood and oxygen to the brain and other vital organs. It is often caused by a heart attack.

In this international, multicenter, randomized , published in the New England Journal of Medicine, researchers described using a microaxial flow pump to move blood from the left ventricle into the aortas of patients who had gone into cardiogenic shock after a severe heart attack. The device successfully lowered the risk of dying from any cause for up to six months. However, patients treated with the microaxial flow pump had a greater risk of developing renal failure and experiencing other adverse events, such as moderate or severe bleeding, decreased blood flow to the limbs and sepsis.

Do nanoplastics pose a risk for cardiovascular disease?

Studies have suggested a potential link between exposure to microplastics and nanoplastics – tiny pieces of plastic that result from its disintegration in the environment – and a greater risk for cardiovascular disease, but there has been little direct evidence to support the theory.

This , multicenter, observational study analyzed plaque specimens taken from patients who had surgery to remove build-up in their carotid arteries, the large vessels in the neck that bring blood to the brain.

Polyethylene – the world's most commonly used plastic, found in everything from grocery bags to bullet proof vests – was present in the carotid artery plaque of more than 58% of patients in the study. Polyvinyl chloride, or PVC plastic, a high-strength material found in products such as medical devices and pipes, also was present in the plaques of 12% of people in the study.

After an average 34 months of follow-up, patients whose carotid artery plaques contained these microplastics had a higher composite risk for heart attacks, strokes and death from any cause than those whose plaques contained no traces of plastic debris.

Exploring new therapies for intracerebral hemorrhage

An intracerebral hemorrhage, or ICH, occurs when a weakened blood vessel ruptures and bleeds into the brain. It is the second most common cause of stroke, accounting for 10-15% of strokes in the U.S. and growing at a faster rate among younger to middle-aged adults than older ones in recent years. This type of stroke is also the most deadly.

Treatment focuses on stopping the bleeding and removing hematomas, or pooled blood, to relieve pressure on the brain. This may include medication or surgery, but whether and how surgery should be done has been controversial.

A new study offers hope for at least some bleeding stroke patients.

(Early, Minimally Invasive Removal of Intracerebral Hemorrhage) is the first trial to show minimally invasive surgery performed within 24 hours of an acute bleeding stroke offered a greater survival benefit to patients than medical management. However, the surgery only improved survival for patients with a lobar hemorrhage – one that occurred in a superficial area of one of the main lobes of the brain – not for those with bleeding deeper in the brain. Researchers stopped enrolling patients with deep brain bleeds when it became apparent the surgery offered them no benefit.

Should beta blockers be prescribed to all heart attack survivors? Maybe not.

Beta blockers are a class of drugs used to treat a variety of heart conditions, including high blood pressure, irregular heartbeats and heart failure. They work by blocking hormones that speed up the heart, lowering blood pressure and making the heart beat slower and with less force. Previous research has shown that giving beta blockers to heart attack survivors may reduce the risk of a new heart attack or death.

The ·¬ÇÑÊÓƵ and American College of Cardiology recommend beta blockers for heart attack survivors, who often take them for at least a year, if not the rest of their lives. But a new study casts doubt on whether this treatment is right for everyone.

presented at the 2024 American College of Cardiology's Annual Scientific Sessions and published in the New England Journal of Medicine suggest this treatment might not be appropriate for people who have acute heart attacks and a preserved ejection fraction of 50% or greater. Among these patients, long-term beta blocker usage did not lower the risk of having another heart attack or dying.

Editor's note: This story was corrected Dec. 18, 2024. An earlier version of this story incorrectly stated that a class of drugs known as non-steroidal mineralocorticoid receptor agonists had been shown to reduce symptoms and mortality in patients with HFrEF. It should have stated that aldosterone antagonists, sometimes called mineralocorticoid receptor antagonists, have been shown to reduce symptoms and mortality in patients with HFrEF, but it was unknown how well a new class of therapies called non-steroidal mineralocorticoid receptor antagonists would work for people with mildly reduced or preserved ejection fraction.