Cardiac Magnetic Resonance IMaging During Arrhythmia

描述（由申请人提供）：本提案的职业发展和研究策略的目标是建立一个独立的临床科学家职业生涯，重点是：1)可靠的成像参数有助于心律失常病理生理和消融手术结果，2)了解患者特异性结构变化如何影响心律失常的传播和对治疗的反应，以及3)发展细胞到器官系统水平的心律失常病理生理的理解，这将作为未来工作的基础。我在临床电生理学、成像科学和计算建模方面的背景非常适合通过个性化图像引导治疗改善心律失常治疗的目标。我的职业发展目标将通过在约翰霍普金斯大学医学院和生物医学工程系的课程学习和指导研究相结合来实现。约翰霍普金斯大学提供了一个令人兴奋的研究和临床环境，并且在以患者为导向的研究方面有着悠久的培养领导者的历史。该机构在研究心脏电生理学和心律失常病理生理学的细胞到器官水平方面具有特别的优势。本职业发展计划的结构化课程部分将包括MRI研究、图像集成计算建模、临床研究设计和研究伦理方面的高级主题培训。这个职业发展奖项的指导研究药剂将集中在心律失常期间的心脏磁共振成像（CMR）。虽然许多速性心律失常可以通过导管消融术治愈，但一些常见疾病，特别是房颤和室性心动过速（VT），目前的医学和消融术治疗效果不佳。心脏磁共振成像（CMR）对心脏电生理学的兴趣越来越大，因为1)CMR有可能显示心肌疤痕和纤维化，这对VT和房颤病理生理很重要，2)CMR有可能显示消融组织以及预定消融区域的间隙。这些间隙可能不会急性传导，因此消融后心律失常可能不会立即复发，但随着时间的推移，间隙可以恢复传导。这种传导恢复可能是消融后心律失常复发的主要机制。CMR可视化间隙的能力，并消除这些可视化间隙，可能会显著降低室性心动过速和消融后房颤复发率。然而，目前用于瘢痕、纤维化和消融病变成像的高分辨率CMR技术在常规临床应用中还不够可靠。拟议的研究将进一步开发在心律失常期间进行更可靠的高分辨率CMR的技术，并将研究相关的CMR应用：1)通过心律失常期间的区域壁运动成像预测成功的消融部位，2)使用抗心律失常CMR热成像预测消融充分性。这项工作的主题是提供更具体和个性化的图像引导治疗，以提高心律失常消融手术的疗效、速度和安全性。

DESCRIPTION (provided by applicant): The aim of the career development and research strategies of this proposal are to build an independent clinician-scientist career focusing on: 1) reliable imaging of parameters that contribute to arrhythmia pathophysiology and ablation procedure outcome, 2) understanding how patient specific structural variations affect arrhythmia propagation and response to treatment, and 3) developing a cellular to organ system level understanding of arrhythmia pathophysiology, that will serve as a basis for future work. My background in clinical electrophysiology, imaging science, and computational modeling is well suited to the goal of improve arrhythmia treatment through individualized image guided therapy. My career development goals will be achieved through a combination of course work and mentored research at the Johns Hopkins University School of Medicine and Department of Biomedical Engineering. Johns Hopkins provides a stimulating research and clinical environment and has a long history of training leaders in patient-oriented research. The institution has a particular strength in studying the cellular to organ level aspects of cardiac electrophysiology and arrhythmia pathophysiology. The structured coursework portion of this career development program will include training in advanced topics in MRI research, image integrated computational modeling, clinical study design, and research ethics. The mentored research potion of this career development award will focus on cardiac magnetic resonance imaging (CMR) during arrhythmia. While many tachy-arrhythmias are curable by catheter ablation, some common conditions, in particular atrial fibrillation and ventricular tachycardia (VT), are sub-optimally managed by current medical and ablation treatments. Cardiac magnetic resonance imaging (CMR) is of increasing interest to cardiac electrophysiology because 1) CMR has the potential to visualize myocardial scar and fibrosis, which are important to VT and atrial fibrillation pathophysiology, and 2) CMR has the potential to visualize ablated tissue as well as gaps in intended regions of ablation. These gaps may not conduct acutely, so that the arrhythmia may not recur immediately after ablation, but the gaps can regain conduction over time. This recovery of conduction is likely a major mechanism for arrhythmia recurrence after ablation. The ability to visualize gaps with CMR, and eliminate those visualized gaps, would likely dramatically reduce the high incidence of VT and atrial fibrillation recurrence after ablation. Current high-resolution CMR techniques for imaging scar, fibrosis, and ablation lesions, however, are not reliable enough for routine clinical application. The proposed research will further develop techniques to perform more reliable high-resolution CMR during arrhythmia and will investigate related CMR applications of 1) predicting successful ablation sites by imaging regional wall motion during arrhythmia and 2) predicting ablation adequacy using arrhythmia resistant CMR thermography. The theme of this work is to provide more specific and individualized image guided therapy toward the goal of increasing the efficacy, speed, and safety of arrhythmia ablation procedures.