MRI cardiovascular catheterization technology development

在过去的一年里，我们使用0.55T的新型低场高性能磁共振成像系统进行了第一次人类心血管磁共振成像。该系统以较低的SAR保存成像，从而允许使用导电金属心血管导丝进行MRI插管。这允许使用基本的金属导管工具，而不会有危险的加热。 与阿德里安·坎贝尔-沃什伯恩的实验室合作，我们正在帮助描述低场下感兴趣组织的基本磁共振特性。 我们证明了阿魏酸甘油(多糖包裹的氧化铁纳米颗粒)用于指示稀释法测量血池的价值，并在大型哺乳动物身上进行了一氧化碳对照验证。对于不同心力衰竭表型的患者，这可能被证明是一种有用的测量方法。 我们研究了低场高性能MRI成像铁敏感标记用于导丝跟踪和导航的价值。 我们探讨了低场(0.55T)实时磁共振成像对射频消融(RFA)和乙醇或醋酸化学消融所致急性心肌损伤的显示能力。初步数据显示，RFA造成的急性损伤很难跨领域力量实时成像。相比之下，化学消融损伤很容易使用实时核磁共振成像显示。这些发现将使结构性心脏病和节律紊乱的新疗法成为可能，包括磁共振导管术。 我们正在与业界密切合作，通过合作研究和开发协议，在介入MRI实验期间以及在X射线和MRI之间传输期间，安全地监测和记录患者的血流动力学。我们正在与业界密切合作，将我们的开发转化为可广泛用于世界各地医疗保健的商业工具。

During the past year we performed first human cardiovascular MRI using a novel low-field and high-performance MRI system at 0.55T. The system preserves imaging with reduced SAR which allows MRI catheterization using conductive metallic cardiovascular guidewires. These allow using fundamental metallic catheter tools without dangerous heating. In collaboration with the laboratory of Adrienne Campbell-Washburn we are helping to characterize fundamental MR properties of tissues of interest at low field. We demonstrated the value of ferumoxytol (polysaccharide coated iron oxide nanoparticles) for indicator-dilution measurement of blood pool, validated against carbon monoxide in large mammals. This may prove a useful measure in patients with different hear failure phenotypes. We have investigated the value of low-field high-performance MRI to image iron susceptibility markers for guidewire tracking and navigation. We have explored the ability of real-time MRI at low field (0.55T) to visualize acute myocardial injury from radiofrequency ablation (RFA) and from chemoablation using ethanol or acetic acid. Preliminary data suggests acute injury from RFA is difficult to image in real-time across field strengths. By contrast, chemoablation lesions are readily visualized using real-time MRI. These findings will enable novel treatments for structural heart disease and rhythm disorders including MRI catheterization. We are working closely with industry, through a Collaborative Research and Development Agreement, system for safe patient hemodynamic monitoring and recording during interventional MRI experiments and during transfer between X-ray and MRI. We are working closely with industry to transfer our developments into commercial tools that can be used widely in medical care throughout the world.