New Version of Blood Test Can Predict Heart Attacks, Strokes Years Before Symptoms
Researchers say the highly sensitive test detects an enzyme that indicates heart damage. Getty Images
Blood tests are widely used to help doctors diagnose heart attacks after a patient experiences symptoms.
Now researchers recently found a more sensitive version of one test that may predict the chances for heart attack or stroke years in advance of any signs of cardiovascular disease.
It’s called the high-sensitivity proportion I test.
The blood test was examined as part of an Atherosclerosis Risk in Communities (ARIC) study designed to investigate the causes and clinical outcomes of atherosclerosis, or clogged arteries.
More than 15,000 middle-aged men and women were enrolled from four communities in the United States.
The research team, using data from this study, concluded that the troponin I test could help predict the onset of cardiovascular issues in healthy middle-aged or older adults.
The researchers examined a group of 8,121 people between 54 and 74 years old from the ARIC study who had no history of cardiovascular disease. Troponin levels were detected in almost 90 percent of them.
According to researchers, people showing no signs of heart disease with elevated troponin I levels were more likely to experience cardiac episodes such as:
The increased risk was independent of other known risk factors, such as high cholesterol levels, blood pressure, smoking, and diabetes.
“We were interested in identifying biomarkers that may help individuals at risk of heart disease but who aren’t typically treated,” Dr. Christie Ballantyne, a study author and a professor of medicine and chief of the section of cardiology at Baylor College of Medicine in Texas, told Healthline.
“As you get middle-aged or older, what we’re seeing is biomarkers of cardiac injury, like troponin, are much better predictors than going by risk factors like cholesterol levels or blood pressure, which are much less informative past someone’s 60s and 70s,” he added.
The enzyme that indicates heart damage
Enzymes are substances the body makes to speed up certain chemical reactions.
After the heart is injured, Ballantyne says, it releases particular enzymes that doctors can test for to confirm the presence of heart damage.
“What was really surprising was we got additional information adding the two types of troponin together. You could have a fairly small panel of these tests to get a very good [cardiovascular disease] risk assessment,” he said.
Troponin levels are normally so low that they can’t be detected, so a positive troponin test typically means the heart has been injured, Ballantyne notes.
The high-sensitivity troponin I test can detect low levels of this enzyme. Researchers said that was associated with a significantly higher risk of cardiovascular disease — even years later.
“Any heart damage can cause elevated troponin levels,” Dr. Aidan R. Raney, an interventional cardiologist with St. Joseph Hospital in California, told Healthline. “As a cardiologist, we usually use these to evaluate for heart attacks caused by coronary disease.”
Ballantyne notes the test is already approved in Europe to evaluate the risk of future cardiovascular events.
“It’s not being used in the U.S. now, but we’ve had some very exciting data, especially regarding heart failure,” he said. “I think the potential for heart failure prevention is very exciting.
The study also found this highly sensitive test was even better at predicting future heart issues when included with the results of a cardiovascular risk calculator. It’s typically used to calculate the 10-year risk of experiencing a heart attack or stroke.
“Physicians typically assess cardiovascular risk with family history, blood pressure, other diseases including diabetes, and history, as well as laboratory studies including cholesterol and inflammation markers,” Raney said.