For perfusion CMR analysis, quantitative tops qualitative for CAD prognosis

Researchers from Germany and the U.K. found quantitative analysis of perfusion cardiac magnetic resonance (CMR) ischemic burden superior to visual analysis in patients with suspected coronary artery disease (CAD), according to a recent Journal of the American College of Cardiology (JACC) study.

“Quantitative analysis provided incremental prognostic value to visual assessment and established risk factors, potentially representing an important step forward in the translation of quantitative CMR perfusion analysis to the clinical setting,” wrote first author Eva. C. Sammut, MD, PhD, at King’s College London, and colleagues.

In clinical practice, stress perfusion CMR is taken qualitatively via visual analysis and has proved beneficial. But mounting research suggests quantification may be superior—specifically in the setting of multivessel coronary disease, authors wrote. But until now, a direct comparison between visual and quantitative perfusion CMR has yet to be done.

The study included patients suspected of having coronary artery disease, who were referred for adenosine-stress perfusion CMR. Perfusion scans were analyzed visually and using quantitative analysis.

A total of 52 patients reached the primary endpoint (defined as a composite of cardiovascular death, nonfatal myocardial infarction, aborted sudden death and revascularization after 90 days) after the median 460-day follow-up. 

Results showed, at two years, ischemic burden increased prognostic value over a baseline model of age, sex and late gandolinium enhancement. The team found their research fell in line with previous literature suggesting “a quantitative approach was also superior to visual assessment in an unselected group of patients from a prognostic perspective,” Sammut et al. wrote.

“The findings of this study have important implications for facilitating more widespread adoption of stress perfusion CMR by less experienced readers and allowing the prognostic value of perfusion quantification to be realized,” authors added.

The group also found support for the current consensus-based prognostic ischemic burden thresholds for perfusion CMR.

“This finding represents a potentially important step forward in the goal of translating quantitative CMR perfusion analysis to the clinical setting,” Sammut et al. wrote. “Our data support the need for larger, multicenter prospective randomized-controlled studies to further explore the prognostic implications of quantitative CMR perfusion analysis.”

In a related JACC editorial, Andrew E. Arai, MD with the National Institutes of Health’s National Heart, Lung and Blood Institute Advanced Cardiovascular Imaging Laboratory, expressed similar enthusiasm for the findings, while cautioning for further research.

“This is an important step forward in understanding the value of quantitative CMR perfusion imaging because there have been relatively few clinical studies that have shown clear benefits over qualitative interpretation,” he wrote.

“Objectively and quantitatively, stress perfusion CMR appears to be in a strong position for assuming a larger role in the management of stable coronary disease,” the group wrote,” Arai added.