Motion-Tracking MRI Tests Reveal Novel Indication of Stroke Risk in A-fib

In a study recently published in the Journal of the American Heart Association, researchers from Johns Hopkins University performed sophisticated motion studies of MRI scans to help predict the stroke risk of people with atrial fibrillation (a-fib). The results from the scans found that specific altered function in the left atrium of the heart may signal stroke risk in those with a-fib and, possibly, those without it. The imaging technique combines standard MRI scans with a motion-tracking software that can analyze cardiac muscle movement. Researchers say the specialized tests can pave the way to more accurate risk-gauging models and more precise therapy for those with the highest likelihood of stroke. The study results, according to the research term, also cast doubt on the current clinical dogma that chaotic beating of the upper chambers of the heart during a-fib fuels the blood clot formation that causes stroke. That view, the team says, has failed to explain why many people with atrial fibrillation never have strokes and why many with history of atrial fibrillation have no evidence of abnormal rhythms within a month before the stroke. “Our research suggests that certain features of the heart’s upper left chamber that are easily seen on heart MRI could be the smoking gun we need to tell apart low-risk from high-risk patients,” said the lead investigator of the study. “Our observations suggest that altered function in the left atrium of the heart may lead to stroke independently of the heart rhythm disturbance itself.” Researchers say the reason why remains unclear, but they believe that the suppressed function and altered anatomy of the left atrium reflect more sluggish blood flow that can lead to clot formation and precipitate stroke. To read more about this study, click here.