EXercise Cardiac Magnetic Resonance Assessment of Left Atrial Mechanics Following Ablation TO Reduce Atrial Fibrillation Burden and Correlation with Exercise CapacitY: EXCLAMATORY Longitudinal Study

项目摘要 心房纤颤是一种非常普遍的疾病，导致心房（心房的顶部腔室）的无序收缩。 心）。四分之一的人在一生中受到影响。已知心律失常具有 与功能失调性心房收缩的双向关系，这种情况本身正在被理解 作为个体可能发展为心力衰竭的手段。然而，大多数已发表的文献， 数据涉及在休息时仰卧检查心房功能，因此不能完全表征不同的心房功能。 一个人在日常生活活动中所经历的努力状态。心血管磁共振成像 共振成像是一种强大的非侵入性诊断方式， 运动，并有可能揭示心房颤动患者可能 进展到明显的心力衰竭-以及目前的治疗技术（即导管消融术）是否可以 改变这个轨迹。 本申请的主要目标是促进主要研究者Cory Trankle博士（医学博士）的培训， 职业生涯作为一个以病人为中心的独立研究人员谁使用运动为基础的诊断模式（包括 磁共振成像），特别关注运动限制的表征机制 例如左心房功能障碍，并将它们鉴定为潜在的生物标志物和治疗靶点， 干预措施。除了教学课程和亚专业研讨会，特朗克尔博士将领导一个 一个多学科团队进行了一项前瞻性临床研究，调查导管消融术对 房颤对运动时心房功能的影响。他将在心房肌无力患者中提出三个具体目标， 接受导管消融术的房颤：（1）确定消融术对左心房功能的影响， 在运动过程中增强其功能，（2）确定消融对左心室性能的影响， 运动，以及（3）确定左心室性能中经历的这些变化是否确实 与左心房功能的改变有关。更好地了解导管消融术的影响， 心房颤动的常见治疗方法，在运动期间对这些心脏结构有可能 确定那些心力衰竭发病率最高的风险，并在这一高度危险的疾病中进行更有针对性的治疗。 流行病。

PROJECT SUMMARY Atrial fibrillation is a highly prevalent condition resulting in disordered contraction of the atria (top chambers of the heart). It affects one in four individuals during their lifetime. It is known that the arrhythmia has a bidirectional relationship with dysfunctional atrial contraction, a condition which itself is becoming understood as a means by which individuals may develop heart failure. However, the majority of published literature to date involves examining atrial function while lying supine at rest, thus incompletely characterizing the varying states of exertion that one experiences during activities of daily living. Exercise-based cardiovascular magnetic resonance imaging is a powerful non-invasive diagnostic modality that can measure heart function during exercise and has the potential to uncover key mechanisms by which patients with atrial fibrillation may progress to overt heart failure – and whether current treatment techniques (namely, catheter ablation) may alter that trajectory. The broad goal of this application is to facilitate training of the principal investigator, Dr. Cory Trankle, MD, for a career as a patient-centered independent researcher who uses exercise-based diagnostic modalities (including magnetic resonance imaging), with a specific interest in characterizing mechanisms of exercise limitations such as left atrial dysfunction and identifying them as potential biomarkers and targets for therapeutic interventions. In addition to didactic coursework and subspecialty seminars, Dr. Trankle will lead a multidisciplinary team conducting a prospective clinical study investigating the effects that catheter ablation for atrial fibrillation has on atrial function during exercise. He will address three specific aims in patients with atrial fibrillation undergoing catheter ablation: (1) determine the effects of ablation on the ability of the left atrium to augment its function during exercise, (2) determine the impacts ablation on left ventricular performance during exercise, and (3) determine whether those changes experienced in left ventricular performance are indeed associated with changes in left atrial function. A better understanding of the impact of catheter ablation, a common treatment for atrial fibrillation, has on these cardiac structures during exercise has the potential to identify those at highest risk for heart failure incidence and lead to more targeted treatment in this highly prevalent disease.