MR-compatible polyetheretherketone-based guide wire assisting MR-guided stenting of iliac and supraaortic arteries in swine: Feasibility study

Abstract

The purpose of this study was to demonstrate first magnetic resonance (MR)-guided stenting of iliac and supraaortic arteries using a polyetheretherketone-based (PEEK) MR-compatible guide wire. In vitro and animal experiments were performed in a short magnet wide-bore scanner (1.5 Tesla, Espree, Siemens Healthcare, Erlangen, Germany). For all experiments, a 0.035'' MR-compatible guide wire prototoype was used. This wire had a compound core of PEEK with reinforcing fibres, a soft and atraumatic tip and a hydrophilic coating. For its passive visualization, paramagnetic markings were attached. All experiments were performed through a vascular introducer sheath under MR-guidance. In vitro repetitive selective over the wire catheterizations of either the right carotid artery and the left subclavian artery were performed. In vivo, selective catheterization and over-the-wire stenting of the brachiocephalic trunk and the left subclavian artery were performed. The common iliac arteries were catheterized retrogradely (left) and cross-over (right). Angioplasty and stenting were performed over-the-wire. All procedures were successful. Visibility of the PEEK-based guide-wire was rated good in vitro and acceptable in vivo. Guide wire pushability and endovascular device support were good. The PEEK-based MR-compatible guide wire is well visible and usable under MR-guidance. It supports over-the-wire treatment of iliac arteries and supraaortic arteries.

Towards real-time cardiovascular magnetic resonance-guided transarterial aortic valve implantation: In vitro evaluation and modification of existing devices

“…While our experiments showed, that the Nu-Med Z-Med II balloon-catheter is suitable for real-time CMR-guidance and may thus be used for balloon valvuloplasty, CMR-compatible guidewires need to be considered for passage of the aortic valve and for propagation of the delivery catheters. According to the literature, there are currently two groups that work towards development and commercialization of first CMR-compatible guidewires [8,9,32-34]. Such CMR-compatible guidewires are polyetheretherketone-based or built from fiberglass or other non-metallic, reinforced components and are passively visualized by their susceptibility artifacts.…”

“…Safe navigation of the valve delivery devices through the vasculature and precise placement of the stent-valve prostheses within the native aortic valve annulus are the challenging key steps of the procedure, which is currently performed under X-ray fluoroscopic and angiographic guidance. X-ray fluoroscopy and angiography, however, entail several shortcomings beyond the inherent harmful effects of radiation exposure which may be overcome by real-time cardiovascular magnetic resonance (CMR) guidance, offering real-time image acquisition with unrestricted scan plane orientation and superior, detailed soft-tissue contrast with simultaneous visualization of the interventional device[3,4] as demonstrated for a variety of vascular procedures in animal studies, including percutaneous transluminal angioplasties[5], selective embolization procedures[6], placement of atrial septal closure devices[7], peripheral[8,9] as well as coronary stent placement[10], stenting of aortic coarctation[11], and aortic stent-graft placement[12]. …”

Multi-selective catheter for MR-guided endovascular interventions

“…Therefore, the use of contrast agent can be significantly reduced compared with angiography. However, to become part of clinical routine, several issues of this imaging modality need to be addressed: increased operational complexity, reduced temporal and spatial resolution, restricted access to the patient and limited patient monitoring, and tremendous amount of noise during the scan [12,[15][16][17]19,20]. Most importantly, MRIguided interventions demand MR compatible instruments [19,20], which are not widely available at the moment.…”

“…Unlike X-ray images, MRI has an excellent soft-tissue contrast [12][13][14][15][16][17]. MRI Table 1 Design requirements for the multi-selective catheter and evaluation of the assembled prototype.…”

“…MRI Table 1 Design requirements for the multi-selective catheter and evaluation of the assembled prototype. flow sensitivity provides angiography, which allows for endovascular interventions with only small amounts or without the use of contrast media [15,18]. Therefore, the use of contrast agent can be significantly reduced compared with angiography.…”