4D flow CMR can be employed to measure in-vivo 3D blood flow dynamics in the heart and atria. Derived flow stasis maps in the left atrium and left atrial appendage are a novel concept to visualize and quantify regions with low flow, known to cause clot formation and risk for stroke. (Credit: Northwestern)

A new imaging technique has been developed that can help predict who is most at risk for stroke. This breakthrough could lead to better treatment and outcomes for patients with atrial fibrillation. The cardiac magnetic resonance (CMR) imaging test can detect the blood’s velocity through the heart and body. Called “atrial 4D flow CMR,” the technique is noninvasive and does not require contrast agents.

The imaging program, which images blood flow dynamically and in the three spatial dimensions, comes in the form of software that can also be integrated into current MRI equipment without the need of special hardware and scanners or equipment upgrades. The software allows the scanner to measure flow, diffusion of molecules, and tissue elasticity.

Historically, physicians have attempted to assess stroke risk in atrial fibrillation patients by using a risk scoring system, which takes risk factors, such as age, general health, and gender, into account. The 4D flow imaging technique can give a more precise assessment of who needs the medication, preventing physicians from overtreating their patients.