Krueger Julia J, Ewert Peter, Yilmaz Sevim, Gelernter Dinah, Peters Björn, Pietzner Klaus, Bornstedt Axel, Schnackenburg Bernhard, Abdul-Khaliq Hashim, Fleck Eckart, Nagel Eike, Berger Felix, Kuehne Titus
Department of Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
Circulation. 2006 Feb 28;113(8):1093-100. doi: 10.1161/CIRCULATIONAHA.105.578112. Epub 2006 Feb 20.
MRI guidance of percutaneous transluminal balloon angioplasty (PTA) of aortic coarctation (CoA) would be desirable for continuous visualization of anatomy and to eliminate x-ray exposure. The aim of this study was (1) to determine the suitability of MRI-controlled PTA using the iron oxide-based contrast medium Resovist (ferucarbotran) for catheter visualization and (2) to subsequently apply this technique in a pilot study with patients with CoA.
The MRI contrast-to-noise ratio and artifact behavior of Resovist-treated balloon catheters was optimized in in vitro and animal experiments (pigs). In 5 patients, anatomy of the CoA was evaluated before and after intervention with high-resolution respiratory-navigated 3D MRI and multiphase cine MRI. Position monitoring of Resovist-treated catheters was realized with interactive real-time MRI. Aortic pressures were continuously recorded. Conventional catheterization was performed before and after MRI to confirm interventional success. During MRI, catheters filled with 25 micromol of iron particles per milliliter of Resovist produced good signal contrast between catheters and their background anatomy but no image distortion due to susceptibility artifacts. All MRI procedures were performed successfully in the patient study. There was excellent agreement between the diameters of CoA and pressure gradients as measured during MRI and conventional catheterization. In 4 patients, PTA resulted in substantial widening of the CoA and a decrease in pressure gradients. In 1 patient, PTA was ineffective.
The MRI method described represents a potential alternative to conventional x-ray fluoroscopy for catheter-based treatment of patients with CoA.
对于主动脉缩窄（CoA）的经皮腔内球囊血管成形术（PTA），磁共振成像（MRI）引导有助于持续观察解剖结构并避免X线辐射。本研究的目的是：（1）确定使用基于氧化铁的造影剂Resovist（ferucarbotran）进行MRI引导的PTA用于导管显影的适用性；（2）随后在CoA患者的初步研究中应用该技术。
在体外和动物实验（猪）中优化了经Resovist处理的球囊导管的MRI对比噪声比和伪影表现。对5例患者，在干预前后采用高分辨率呼吸导航3D MRI和多期电影MRI评估CoA的解剖结构。通过交互式实时MRI实现对经Resovist处理导管的位置监测。连续记录主动脉压力。在MRI前后进行传统导管插入术以确认介入成功。在MRI期间，每毫升Resovist中填充25微摩尔铁颗粒的导管在导管与其背景解剖结构之间产生了良好的信号对比，且未因磁敏感伪影导致图像失真。在患者研究中所有MRI操作均成功完成。MRI测量的CoA直径与压力梯度和传统导管插入术测量结果之间具有高度一致性。4例患者中，PTA使CoA明显增宽且压力梯度降低。1例患者中，PTA无效。
所描述的MRI方法是CoA患者基于导管治疗的传统X线透视的一种潜在替代方法。
