Atrial fibrillation ablation assessment and guidance using native-contrast T1 weighted MRI

点击翻译按钮获取中文摘要

Project Summary: Atrial fibrillation (Afib) is a common arrhythmia that is currently difficult to manage. Afib catheter ablation is more effective than medical therapy for maintaining normal rhythm. However, treatment failure is common, around 50% for persistent forms of Afib. Attempts to improve outcomes by performing more extensive ablation have been limited by new arrhythmias, like atrial flutter, which can be caused by the procedure. Outcomes can be improved by repeat procedures, but arrhythmia recurrence is still common. Surgical procedures have higher success for treating Afib, but the successful techniques are prohibitively invasive for treating most patients. Methods to improve the success of the first Afib catheter ablation procedure are needed. Ablation failure is thought to be due to the inability to create properly placed, permanent ablation lesions. Currently, transient tissue injury and edema caused by ablation can make ablation appear complete at the end of the procedure. However, as transient injury resolves over days to weeks, arrhythmia can recur. Current methods for determining whether ablation is finished cannot tell the difference between permanent and transient tissue injury. Methods that show where additional ablation needs to be performed and confirm that permanent ablation has been completed are expected to improve the success of Afib ablation. We have developed a non-contrast MRI method for seeing permanent ablation lesions. We recently showed this method can see ablation lesions in the thin walled atrium, which is the part of the heart that causes Afib. Because this method does not need intravenous contrast, it can be repeated during a procedure until complete ablation is confirmed. This proposal will find out if this method can 1) detect sites of incomplete Afib ablation, 2) guide additional ablation to these sites, and 3) confirm ablation is complete at the end of the procedure. This proposal also translates this method, previously developed in animals, to patients undergoing Afib ablation. Effective acute assessment of ablative treatment would provide an important component of feedback not currently available for procedure guidance. Successful completion of these aims will introduce a new paradigm for confirming ablation completion in order to reduce arrhythmia recurrence following AFib ablation. These methods could also be applied to other arrhythmias where incomplete ablation contributes to poor ablation outcomes, like ventricular tachycardia.