Fewer heart attacks, but more deaths from failure and arrhythmias

While heart disease has been the leading cause of death in the U.S. for over a century, the past 50 years have seen a substantial decrease (66%) in overall age-adjusted heart disease death rates, including a nearly 90% drop in heart attack deaths, according to new research published in the Journal of the American Heart Association<.

During that time, there have been major shifts in the types of heart disease people are dying from, with large increases in deaths from heart failure, arrhythmias and hypertensive heart disease.

In an analysis of data from the U.S. Centers for Disease Control and Prevention, researchers reviewed the age-adjusted rates of heart disease deaths among adults aged 25 and older from 1970 to 2022. The analysis found:

Over this 52-year period, heart disease accounted for nearly one-third of all deaths (31%).
During this time, heart disease death rates decreased substantially, from 41% of total deaths in 1970 to 24% of total deaths in 2022.
In 1970, more than half of all people who died from heart disease (54%) died because of a heart attack—a type of acute ischemic heart disease. The age-adjusted death rate decreased 89% by 2022, when less than one-third of all heart disease deaths (29%) were caused by a heart attack.
Conversely, during this time, the age-adjusted death rate from all other types of heart disease (including heart failure, hypertensive heart disease and arrhythmia) increased by 81%, accounting for 9% of all heart disease deaths in 1970 and 47% of all heart disease deaths in 2022.

“This distribution shift in the types of heart disease people were dying from the most was very interesting to us,” said the study’s first author, Sara King, M.D., a second-year internal medicine resident in the department of medicine at Stanford School of Medicine in Stanford, California.

“This evolution over the past 50 years reflects incredible successes in the way heart attacks and other types of ischemic heart disease are managed. However, the substantial increase in deaths from other types of heart conditions, including heart failure and arrhythmias, poses emerging challenges the medical community must address.”

During the decades reviewed:

Deaths from arrhythmias had the largest relative increase, with the age-adjusted death rate rising by 450%. However, arrhythmias still accounted for only about 4% of all heart disease deaths in 2022. Arrhythmias occur when electrical impulses to the heart may be too fast, too slow or erratic, causing an irregular heartbeat. Atrial fibrillation is one of the most common types of arrhythmias.
The age-adjusted death rate from heart failure—a chronic condition where the heart is unable to pump enough blood to meet the body’s needs for blood and oxygen—increased by 146%. The rate of deaths from hypertensive heart disease—heart problems that occur because of high blood pressure that is present over a long time—increased by 106%.

In addition to analyzing the types of heart disease deaths, the researchers also identified several underlying factors that may account for the shift in deaths from ischemic heart disease to other heart conditions.

“Over the past 50 years, our understanding of heart disease, what causes it and how we treat it has evolved considerably. That’s especially true in how we address acute cardiac events that may appear to come on suddenly,” King said.

“From the establishment and increased use of bystander CPR and automated external defibrillators to treat cardiac arrest outside the hospital setting, to the creation of systems of care that promote early recognition of and quick procedural and medical intervention to treat heart attacks, there have been great strides made in helping people survive initial acute cardiac events that were once considered a death sentence.”

Other specific advancements noted in the study included:

The invention in the 1960s of coronary artery bypass grafting and the formation of coronary care units improved in-hospital and long-term heart disease death rates.

Cardiac imaging improved in the 1970s with coronary angiography, which was capitalized by the advent of balloon angioplasty in 1977, followed by coronary stenting to open blocked heart arteries in the 1980s to 1990s.

Simultaneously, there was significant development of medical therapies in the 1970s to 1990s, including thrombolytics and aspirin to reduce blockages; beta blockers to treat high blood pressure; renin-angiotensin-aldosterone system inhibitors to slow the progression of heart and kidney disease; and statins to control cholesterol. These advances all contributed to the decline in deaths from treatment and deaths due to a second or subsequent acute cardiac event.

At the turn of the 21st century, high-intensity statin therapy to lower cholesterol and dual antiplatelet therapy to reduce clotting were established, as well as landmark “door-to-balloon” trials that displayed substantial benefits when care to open blocked arteries was expedited.

From 2009 to 2022, high-sensitivity troponins that improved the rapid diagnosis of heart attacks and advanced antiplatelet agents to reduce clotting and restore blood flow to the heart further improved death rates, while lipid-lowering therapies such as ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors emerged to improve options for secondary prevention.

In addition to medical advances, significant public health strides, such as smoke-free policies, increased emphasis on physical activity and updated practice guidelines that support improved blood pressure and cholesterol management, have driven much of the improvements, according to the report.

Study researchers point out that, despite the overall reduction in heart disease and the progress in therapies and guidelines, there has been a substantial rise in many CVD risk factors, such as obesity, type 2 diabetes, hypertension and physical inactivity, in the United States. An aging population is also contributing to an increase in the types of heart disease people are dying from. The report found:

From the 1970s to 2022, obesity prevalence has risen from 15% to 40%.
Type 2 diabetes, including prediabetes, has risen to impact nearly half of all adults in the U.S. in 2020.
Hypertension has increased from a prevalence of approximately 30% in 1978 to nearly 50% in 2022.
Demographic shifts in the U.S. have also contributed significant changes to the landscape of heart disease mortality. From 1970 to 2022, there has been a notable increase in life expectancy, from 70.9 years to 77.5 years.

“All of these risk factors contribute to an ongoing burden of heart disease, especially as related to heart failure, hypertensive heart disease and arrhythmias,” said senior author of the paper Latha Palaniappan, M.D., M.S., FAHA, associate dean for research and a professor of medicine at Stanford University School of Medicine.

“While heart attack deaths are down by 90% since 1970, heart disease hasn’t gone away. Now that people are surviving heart attacks, we are seeing a rise in other forms of heart disease like heart failure. The focus now must be on helping people age with strong, healthy hearts by preventing events, and prevention can start as early as childhood.”

The authors note several limitations to this study:

There are likely substantial differences in these reductions in heart disease deaths by age, sex, race, ethnicity, region and urbanization. The study did not analyze data including these components, and research including these factors should be prioritized in future studies to confirm if these overall trends remain valid in subpopulations.

The use of multiple iterations of the International Classification of Diseases (ICD) coding system may allow for potential miscoding and presents challenges in maintaining consistency in comparisons across the years. Particularly prominent is the change from ICD-8 to ICD-9 in the year 1979, where the mortality of several conditions (valvular heart disease, hypertensive heart disease, pulmonary heart disease) dramatically increased.

The true burden of ischemic heart disease may be underestimated in the findings presented in this study, since certain conditions, including heart failure, cardiomyopathy, arrhythmias and, in particular, ventricular arrhythmias and cardiac arrest, may be overly simplistic. Many of these cases likely have underlying causes that cannot be precisely differentiated using current or past ICD codes.