Use of the novel magnetic navigation system Niobe in percutaneous coronary interventions; the Hamburg experience

In interventional cardiology an increasing demand to treat complex coronary lesions (i.e. distal lesions, tortuous vessels, chronic occlusions) has developed within the last years. New devices to fulfill this demand are therefore needed.

The magnetic navigation system (Niobe System; Stereotaxis Inc.) represents a novel system which allows 3-dimensional control of the guide wire tip using magnetic fields. Two computer controlled permanent magnets on each side of the patient create a uniform magnetic field which can freely be directed. A small magnet at the guide wire tip will align according to the vector of the magnetic field. Advancing and retracting of the wire is to be done manually. The remaining steps of angioplasty (i.e. balloon angioplasty and stent implantation) are performed conventionally, after magnetically guided crossing of the target lesion.The study was performed to proof the feasibility of the technique in the treatment of coronary lesions. Seventy seven patients with 82 coronary lesions underwent magnetic guided coronary interventions. Sixty three lesions (77%) could be crossed successfully using magnetic guidance, 13 more by switching to conventional guide wires. Successful angioplasty (with or without stent implantation) was achieved in 74 lesions (90%). Mean fluoroscopy time was 13,9+/-8 min.

The use of magnetic guidance in coronary interventions is a promising tool to treat complex coronary lesions. With more experience and improved devices (i.e. coated wires, steerable microcatheters) the safety and efficacy of the procedures should be improved.