Coronary CTA identifies high-risk plaque leading to CV events
High-risk plaque detected by coronary CTA was linked to future major adverse CV events in patients with stable chest pain, according to new data from the PROMISE trial.
As Cardiology Today previously reported, in the main results of PROMISE, low-risk patients with suspected CAD had no differences in outcomes at 2 years regardless if they were evaluated with CTA or functional testing.
For the present secondary analysis, researchers analyzed if high-risk plaque detected by coronary CTA was independently linked to major adverse CV events regardless of significant stenosis or CV risk factors.
Maros Ferencik, MD, PhD, MCR, from the Knight Cardiovascular Institute at Oregon Health and Science University, and colleagues evaluated 4,415 patients who underwent CTA in PROMISE (mean age, 61 years; 52% women). Median atherosclerotic CVD risk score was 11, and 3% had major adverse CV events during a median follow-up of 25 months.
According to the researchers, 15.3% of patients had high-risk plaques and 6.3% had significant stenosis.
Risk for events
Those with high-risk plaques had a 6.4% rate of major adverse CV events vs. 2.4% for those without them (HR = 2.73; 95% CI, 1.89-3.93.) The elevated risk associated with high-risk plaques remained after adjustment for atherosclerotic CVD risk score and significant stenosis (adjusted HR = 1.72; 95% CI, 1.13-2.62).
Net reclassification improvement was significant after addition of high-risk plaque to the atherosclerotic CVD risk score and significant stenosis assessment (0.34; 95% CI, 0.02-0.51), Ferencik and colleagues wrote.
In patients with nonobstructive CAD, high-risk plaque was associated with increased risk for major adverse CV events (aHR for patients with high-risk plaque = 4.31; 95% CI, 2.25-8.26; aHR for patients without high-risk plaque = 2.64; 95% CI, 1.49-4.69).
In patients with significant stenosis, there was no difference in risk for major adverse CV events in those with high-risk plaque (aHR = 8.68; 95% CI, 4.25-17.73) and those without it (aHR = 9.31; 95% CI, 4.21-20.61), according to the researchers.
High-risk plaque had a stronger association with major adverse CV events in women (aHR = 2.41; 95% CI, 1.25-4.64) than in men (aHR = 1.4; 95% CI, 0.81-2.39) and in younger patients (aHR = 2.33; 95% CI, 1.2-4.51) than in older patients (aHR = 1.36; 95% CI, 0.77-2.39).
“The detection of high-risk plaque added the most value in patients with nonobstructive CAD, younger patients and women,” Ferencik and colleagues wrote. “High-risk plaque may constitute an additional risk stratification tool for clinical management. However, because absolute event rates were low and the positive predictive value of high-risk plaque was diminished, the findings may be of limited applicability to clinical management strategies.”
Benefit may be limited
In a related editorial, Raymond J. Gibbons, MD, professor of medicine and consultant in the division of ischemic heart disease and critical care in the department of cardiovascular medicine at Mayo Clinic in Rochester, Minnesota, and past president of the American Heart Association, agreed with Ferencik and colleagues.
“Because the positive predictive value of the presence of high-risk plaque for MACE was only 6.4% (and could probably be estimated at approximately 3% for hard cardiac events), only 1 in 33 patients with high-risk plaque with have a hard cardiac event and, therefore, potentially benefit,” he wrote. “Since high-risk plaque did not predict more MACE in those with significant stenosis ... percutaneous coronary intervention would seem to be of limited value.” – by Erik Swain
Disclosure: Ferencik reports he received a grant from the AHA. Please see the study for the other authors’ relevant financial disclosures. Gibbons reports he receives personal fees from Astellas Pharmaceuticals and Peer View Institute.