Stress Cardiac MRI Identifies Hidden Heart Issues When Angiograms Show Clear Arteries

Stress cardiac MRI testing may help improve diagnosis and treatment for people with chest pain even when coronary angiogram testing shows the main heart arteries appear clear. Research presented at the American Heart Association's Scientific Sessions 2025 found that using cardiac stress MRI uncovered small vessel problems in about half of participants who had prior coronary angiography indicating no obstructive coronary artery disease. According to study author Colin Berry, M.B.Ch.B., Ph.D., professor of cardiology at the University of Glasgow, "People may have real angina even when the main arteries appear wide open. By measuring blood flow with a stress cardiac MRI test, we found that small vessel problems were common. Our findings show that an angiogram alone is not always enough to explain chest pain."

The CorCMR trial enrolled 250 adults with chest pain but no blocked coronary arteries based on previous testing. All participants had a coronary angiogram test within three months prior to enrollment, with results indicating suspected angina and no obstructive coronary arteries. Participants were randomly assigned to two groups, with one group having stress cardiac MRI results shared with doctors to guide diagnosis and treatment, while the other group received treatment based only on angiogram results. After following participants for at least 12 months, the analysis revealed significant findings. About half of all participants experienced a diagnosis change after the stress cardiac MRI was completed. Approximately one in two participants had chest pain from small vessels in the heart, diagnosed as microvascular angina, while about 48% had chest pain not linked to the heart, and 2% had other conditions such as heart muscle inflammation or thickened heart muscle.

When doctors reviewed stress cardiac MRI images, about one in two participants were diagnosed with microvascular angina, compared with fewer than one in 100 when doctors relied only on angiogram tests. More than half of those diagnosed with microvascular angina were women, highlighting the particular importance of this testing for female patients. Quality of life outcomes showed substantial improvements in the stress cardiac MRI group. Using the Seattle Angina Questionnaire, which assesses physical mobility, chest pain frequency and severity, and quality of life, participants in the stress cardiac MRI group improved by an average of 18 points at six months and 22 points at one year. In contrast, people in the angiogram-guided group improved by less than 1 point, resulting in a 21-point difference between groups after one year.

The study, coordinated by an independent clinical trials unit with data analyzed by a blinded statistician to minimize bias, found no serious side effects from stress cardiac MRI screening and no deaths during the year of follow-up. Berry emphasized that "clinical practice should now change to include a stress cardiac MRI test for angina, especially for women with chest pain and no blockages in the main arteries." These findings are particularly significant given that chest pain is the second most common reason adults visit hospital emergency departments in the U.S., accounting for more than 6.5 million visits each year according to the American Heart Association's Heart Disease and Stroke Statistics – 2025 Update available at https://www.heart.org. The research abstract can be viewed in the American Heart Association Scientific Sessions 2025 Online Program Planner at https://professional.heart.org.