Real-time MRI guided cardiovascular intervention

点击翻译按钮获取中文摘要

During the past year we have continued our work applying rapid MRI to guide simple and complex mechanical and biological interventions. We reported the first careful comparison of conventional X-ray and wholly MRI guided transfemoral pulmonary artery catheterization in adults. In this pilot, we found that radiation-free MRI catheterization is safe and feasible. Guidewire-free MRI catheterization was just as successful as X-ray catheterization (more so in specific challenging procedure steps) and took approximately the same time. We continue to perform X-ray-free MRI catheterization in patients whenever possible. We performed the first ever MRI pericardiocentesis procedure in humans. We have developed still another novel access port into the heart across the chest wall, as an alternative to surgery to implant large cardiac appliances such as mitral valve replacements. In this novel approach, we enter the left ventricle across the interventricular septum. This allows the dangerous port to pericardial space to enjoy low pressure, and the right ventricle to serve as the high-pressure pop-off chamber. We found unexpectedly that the interventricular septum closes tightly, immediately, and heals spontaneously as a very small scar. We intend these also to allow direct repair of congenital heart defects on small children who otherwise might require open surgical access. We have begun work on challenges in pediatric cardiology, starting with a non-surgical pulmonary artery resistor device to help reduce the complexity of cardiac surgery for certain congenital heart defects. We are developing other novel catheterization tools, for example, to access the aorta without surgery in patients with severe peripheral artery disease. NHLBI Cardiothoracic Surgery Research Branch investigators have used our interventional MRI system and environment to further test the feasibility and utility of real-time MRI guidance for surgical transapical implantation of a custom aortic stent valve bioprosthesis in swine. Overall we have successfully developed novel applications of real-time MRI for cardiovascular treatments, and we continue to work to clinical applications of these exciting new developments.