"We show that different cardiac MRI markers of atrial fibrosis -- percentage of positive [late gadolinium enhancement] and T1 relaxation times -- were significantly elevated in patients with a recurrence of atrial fibrillation," said Dr. Julian Luetkens of the radiology department at the University of Bonn. "Both parameters were independent predictors of poor outcome following ablation therapy."
The prospective study included 61 patients with a mean age of 60.3 years. Left atrial late gadolinium enhancement and left atrial T1 mapping were performed during preprocedural cardiac MRI. Patients were categorized by four different fibrosis stages based on the percentage of left atrial wall enhancement on late-enhancing MRI scans.
At one year of follow-up, atrial fibrillation recurred in 20 (33%) subjects. Patients with a recurrence of atrial fibrillation showed a higher mean percentage of left atrial wall enhancement, higher left atrial T1 relaxation times, and a higher plasma level of relaxin. A multivariate analysis also revealed that poor ablation outcome was best predicted by advanced fibrosis stage and higher T1 relaxation times.
"Preprocedural cardiac MRI seems to be a valuable tool for prediction of poor response to catheter ablation therapy in patients with atrial fibrillation," Luetkens told AuntMinnie.com. "It offers various imaging techniques for outcome prediction and might be valuable for better patient selection prior to ablation therapy."
