Noninvasive MRI Technique Shows Promise as Alternative to Cardiac Catheterization

Routine MRI scans may soon help patients avoid invasive cardiac testing, thanks to new research from the University of East Anglia in Norwich, England. The findings suggest that blood oxygen measurements acquired through T2 mapping during cardiac MRI can offer the same diagnostic insights as right heart catheterization—a standard, yet invasive, procedure used to assess heart failure.

Right heart catheterization plays a key role in evaluating patients with advanced heart failure by measuring oxygen saturation levels in the blood. While effective, the procedure involves inserting a catheter through a vein, which carries risks—particularly for older or critically ill individuals. Seeking a safer alternative, researchers developed a noninvasive method for obtaining the same hemodynamic data using magnetic resonance imaging.

“We wanted to develop a safe, noninvasive alternative, which could allow far more patients to be properly assessed—and allow repeat monitoring without the risks of a catheter test,” said Pankaj Garg, MD, consultant cardiologist at Norfolk and Norwich University Hospital and lead author of the study. “Our breakthrough could be a game changer for assessing advanced heart failure."

According to the researchers, blood with varying levels of oxygen behaves differently when exposed to a magnetic field. Using this principle, they applied T2 mapping techniques during MRI scans and developed a formula to calculate oxygen saturation without the need for catheter insertion.

Initial validation of the formula was conducted in a cohort of 60 patients who had undergone both cardiac MRI and right heart catheterization. The results from the noninvasive MRI closely matched those from catheter-based measurements, prompting further research. The team then applied the technique in a larger study involving 628 patients with newly diagnosed heart failure. These patients were followed for three years after undergoing cardiac MRI.

The study found that individuals with healthier MRI-derived oxygen readings had significantly better clinical outcomes. They were less likely to be hospitalized or die from heart failure-related causes, regardless of their age or underlying health conditions.

“This means we may be able to read off a crucial hemodynamic number from an everyday scan—effectively turning a routine MRI into a much more powerful test, without putting a tube into the heart,” said senior author Peter Swoboda, PhD, of the University of Leeds.

The researchers believe this approach could expand access to cardiac diagnostics, particularly for patients who are not ideal candidates for invasive testing. However, they note that additional research involving larger, diverse populations is needed before the technique can be adopted into routine clinical practice.