By using PET/CT to measure the level of calcium in the coronary arteries during stress tests, clinicians can better predict which patients are at high risk of heart disease, according to a study presented on Monday at the American College of Cardiology (ACC) annual conference in Orlando, FL.
In a review of more than 8,000 patients, researchers at the Intermountain Medical Center Heart Institute in Salt Lake City found that the presence of calcium in the coronary arteries led to more coronary angiographies, revascularizations, major adverse cardiac events, and deaths.
Of the 8,213 patients in the study, 4,318 (53%) were found to have no calcium in their coronary arteries, while 3,805 (47%) showed evidence of calcium. All patients had no history of coronary artery disease (CAD), heart attack, or known restricted blood flow to the heart; had visited a physician clinic or the hospital with symptoms of suspected heart disease; and had received a PET/CT imaging study from 2013 to 2016.
So, how did the discovery of calcium influence their short-term health?
Within 60 days, the data showed the following:
- 10.8% of patients with calcium underwent coronary angiography, compared with only 3.6% of patients with no calcium (p < 0.001).
- 6.5% of patients with calcium in their coronary arteries received revascularization to restore blood flow to the heart, compared with 0.8% of patients with no calcium who underwent the procedure (p < 0.001).
In addition, the researchers reported findings after two years:
- A major adverse cardiac event occurred in 6% of patients with calcium, compared with 1.9% of those with no calcium (p < 0.001).
- 4.2% of patients with calcium died, compared with 1.4% who were calcium-free (p < 0.001).
By performing a PET/CT scan to measure coronary artery calcium, clinicians could better determine the potential risk and presence of heart disease, concluded lead author Viet Le, a physician's assistant and cardiovascular researcher.
"High blood pressure, diabetes, high cholesterol, and smoking are all risks of heart disease, yet many people who have those risks never have the disease or suffer an event," he said in a statement. "Coronary artery calcium is the disease, and to an extent, it shows just how much of the disease is present."
The PET/CT test also has the potential to reduce healthcare costs proactively, Le and colleagues noted.
"Avoiding a heart attack is a huge economic benefit," Le said. "A similar benefit comes as clinicians prescribe medications more efficiently by identifying precisely who needs them."
