Nav: Home

Artificial intelligence improves heart attack risk assessment

June 25, 2019

OAK BROOK, Ill. - When used with a common heart scan, machine learning (ML), a type of artificial intelligence, does better than conventional risk models at predicting heart attacks and other cardiac events, according to a study published in the journal Radiology.

Heart disease is the leading cause of death for both men and women in the United States. Accurate risk assessment is crucial for early interventions including diet, exercise and drugs like cholesterol-lowering statins. However, risk determination is an imperfect science, and popular existing models like the Framingham Risk Score have limitations, as they don't directly consider the condition of the coronary arteries.

Coronary computed tomography arteriography (CCTA), a kind of CT that gives highly detailed images of the heart vessels, is a promising tool for refining risk assessment--so promising that a multidisciplinary working group recently introduced a scoring system for summarizing CCTA results. The decision-making tool, known as the coronary artery disease reporting and data system (CAD-RADS), emphasizes stenoses, or blockages and narrowing in the coronary arteries. While CAD-RADS is an important and useful development in the management of cardiac patients, its focus on stenoses may leave out important information about the arteries, according to study lead author Kevin M. Johnson, M.D., associate professor of radiology and biomedical imaging at the Yale School of Medicine in New Haven, Conn.

Noting that CCTA shows more than just stenoses, Dr. Johnson recently investigated an ML system capable of mining the myriad details in these images for a more comprehensive prognostic picture.

"Starting from the ground up, I took imaging features from the coronary CT," he said. "Each patient had 64 of these features and I fed them into a machine learning algorithm. The algorithm is able to pull out the patterns in the data and predict that patients with certain patterns are more likely to have an adverse event like a heart attack than patients with other patterns."

For the study, Dr. Johnson and colleagues compared the ML approach with CAD-RADS and other vessel scoring systems in 6,892 patients. They followed the patients for an average of nine years after CCTA. There were 380 deaths from all causes, including 70 from coronary artery disease. In addition, 43 patients reported heart attacks.

Compared to CAD-RADS and other scores, the ML approach better discriminated which patients would have a cardiac event from those who would not. When deciding whether to start statins, the ML score ensured that 93 percent of patients with events would receive the drug, compared with only 69 percent if CAD-RADS were relied on.

"The risk estimate that you get from doing the machine learning version of the model is more accurate than the risk estimate you're going to get if you rely on CAD-RADS," Dr. Johnson said. "Both methods perform better than just using the Framingham risk estimate. This shows the value of looking at the coronary arteries to better estimate people's risk."

If machine learning can improve vessel scoring, it would enhance the contribution of noninvasive imaging to cardiovascular risk assessment. Additionally, the ML-derived vessel scores could be combined with non-imaging risk factors such as age, gender, hypertension and smoking to develop more comprehensive risk models. This would benefit both physicians and patients.

"Once you use a tool like this to help see that someone's at risk, then you can get the person on statins or get their glucose under control, get them off smoking, get their hypertension controlled, because those are the big, modifiable risk factors," he said.

Dr. Johnson is currently working on a paper that takes results from this study and folds them into the bigger picture with non-imaging risk factors.

"If you add people's ages and particulars like smoking, diabetes and hypertension, that should increase the overall power of the method and improve the overall results," he said.
-end-
"Scoring of Coronary Artery Disease Characteristics on Coronary CT Angiograms by Using Machine Learning." Collaborating with Dr. Johnson were Hilary E. Johnson, B.A., Yang Zhao, Ph.D., David A. Dowe, M.D., and Lawrence H. Staib, Ph.D.

Radiology is edited by David A. Bluemke, M.D., Ph.D., University of Wisconsin School of Medicine and Public Health, Madison, Wis., and owned and published by the Radiological Society of North America, Inc. (https://pubs.rsna.org/journal/radiology)

RSNA is an association of over 53,400 radiologists, radiation oncologists, medical physicists and related scientists promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill. (RSNA.org)

For patient-friendly information on CCTA, visit RadiologyInfo.org.

Radiological Society of North America

Related Heart Attack Articles:

Where you live could determine risk of heart attack, stroke or dying of heart disease
People living in parts of Ontario with better access to preventive health care had lower rates of cardiac events compared to residents of regions with less access, found a new study published in CMAJ (Canadian Medical Association Journal).
Activated T-cells drive post-heart attack heart failure
Chronic inflammation after a heart attack can promote heart failure and death.
ICU care for COPD, heart failure and heart attack may not be better
Does a stay in the intensive care unit give patients a better chance of surviving a chronic obstructive pulmonary disease (COPD) or heart failure flare-up or even a heart attack, compared with care in another type of hospital unit?
Heart attack treatment might be in your face
Researchers at the University of Cincinnati have received $2.4 million in federal funding to pursue research on a novel cell therapy that would repair heart damage using modified cells taken from the patient's own facial muscle.
Tissue engineering advance reduces heart failure in model of heart attack
Researchers have grown heart tissue by seeding a mix of human cells onto a 1-micron-resolution scaffold made with a 3-D printer.
Study shows functional effects of human stem cell delivery to heart muscle after heart attack
Researchers delivered human stem cells seeded in biological sutures to the damaged heart muscles of rats following induced acute myocardial infarction and assessed the effects on cardiac function one week later.
Younger heart attack survivors may face premature heart disease death
For patients age 50 and younger, the risk of premature death after a heart attack has dropped significantly, but their risk is still almost twice as high when compared to the general population, largely due to heart disease and other smoking-related diseases The risk of heart attack can be greatly reduced by quitting smoking, exercising and following a healthy diet.
After the heart attack: Injectable gels could prevent future heart failure (video)
During a heart attack, clots or narrowed arteries block blood flow, harming or killing cells in the heart.
Heart failure after first heart attack may increase cancer risk
People who develop heart failure after their first heart attack have a greater risk of developing cancer when compared to first-time heart attack survivors without heart failure, according to a study today in the Journal of the American College of Cardiology.
1 in 4 patients develop heart failure within 4 years of first heart attack
One in four patients develop heart failure within four years of a first heart attack, according to a study in nearly 25,000 patients presented today at Heart Failure 2016 and the 3rd World Congress on Acute Heart Failure by Dr.

Related Heart Attack Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...