MRI-based visualization and acute targeting of gaps in atrial ablation lesions

描述（由申请人提供）：此提案描述了一个为期五年的培训计划，以发展心脏电生理学的学术生涯。首席研究员对心脏电生理研究有长期的兴趣。在这项资助的过程中，申请人将获得培训和资金，成为一名独立的研究者，其长期目标是了解心律失常的机制和开发新技术，从而导致更有效的治疗方案。在接下来的五年中，申请人将接受核磁共振成像技术和临床研究方面的正式教学培训。研究者将由Dennis Parker博士和一个由MRI研究、临床电生理学、图像处理和生物统计学领域的专家组成的委员会进行指导。Parker博士是MRI研究领域的领导者，拥有独立的NIH资助和多年的指导经验。在培训计划的开始，研究计划将集中于开发MRI可视化技术，以可视化消融病变集的间隙，目的是测试针对这些间隙的假设

DESCRIPTION (provided by applicant): This proposal describes a five-year training program to develop an academic career in cardiac electrophysiology. The principal investigator has a long-standing interest in cardiac electrophysiology research. Over the course of this grant, the applicant will obtain the training and funding to become an independent investigator with the long-term goal of understanding arrhythmia mechanisms and developing new technologies, leading to more efficacious treatment regimens. Over the next five years the applicant will undergo formal didactic training in Magnetic Resonance Imaging (MRI) techniques and clinical investigation. The investigator will be mentored by Dr. Dennis Parker, along with a committee comprised of experts in the field of MRI research, clinical electrophysiology, image processing and biostatistics. Dr. Parker is a leader in the field of MRI research with independent NIH funding and many years of mentoring experience. At the onset of this training program, the research program will be focused on developing MRI visualization techniques to visualize gaps in ablation lesion sets with the goal to test the hypothesis that targeting these gaps acutely will lead to improved outcomes. The success rate for ablation in atrial fibrillation remains persistently low and can require multiple procedures, leaving room for significant improvement. The goal in most of these ablation procedures is to isolate a region with sources of electrical "triggers" from tissue susceptible to such triggers by creating a line of tissue burns or ablation lesions. For such ablation lines to be effective, the lines should have no gaps. Currently, there i no effective means to provide direct proof of successful lines of lesion or ablation and the evaluation of success depends on indirect markers that are often poor predictors. MRI has exceptional capabilities for visualizing soft tissue. These proposed studies aim to develop MRI-based techniques to visualize and evaluate radiofrequency ablation lesions and target gaps in lesion sets. The specific aims for this project are: 1) to determine the smallest gap in ablation lesion sets that can be detected by MRI and then targeted acutely, 2) to test the hypothesis that identifying and targeting gaps acutely will lead to significant improvement in maintaining electrical isolation over time, and 3) to test the hypothesis that gaps detected by MRI in ablation lines will predict electrical reconnection and arrhythmia recurrence in humans. Success in these studies will greatly expand our ability to target gaps in ablation lesion sets acutely leading to improved outcomes from ablation procedures. Moreover, these studies, didactic training in MRI, and clinical investigation and mentoring during this period, will prepare the applicant to pursue rigorous hypothesis testing research. These studies will also form the basis of the next set of studies in animal models of atrial fibrillation, and finally, in humans. We already have a number of species of large animal models of atrial fibrillation as part of another funded project, which makes this research all the more attractive.