Remote magnetic navigation

Remote Magnetic Navigation is an emerging technology in interventional cardiology. Catheters with magnetic tips can be steered within the patient, without the need for an electrophysiologist to maneuver the catheter placement manually. The engineering was developed at the University of Virginia, and the patent rights were later acquired by Stereotaxis, Inc. to market and develop a magnetic navigation system, according to its 2005 10-K filing with the SEC.

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Traditional catheter labs in hospitals rely on the manual placement and steering of catheters by a physician. In interventional cardiology, catheters are used to map the cardiovascular system and to correct arrhythmias and atrial fibrillation, among other heart related problems, through a variety of methods including ablation. The patient is placed under a flouroscopic system, such as a C-arm, to give the EP real-time feedback on the positioning of the catheter. In manual procedures, the physician must wear a lead apron due to radiation exposure.

Remote magnetic navigation operates by using two large magnets placed on either side of the patient, and alterations in the magnetic field produced by the magnets deflects the tips of catheters within the patient to the desired direction. The EP operates the catheter placement from a side table with screens and a joyce stick. Stereotaxis offers software which enables automated mapping and other advantages through its Navigant suite. Due to the lack of irrigated catheters, completing ablation procedures with magnetic navigation has been difficult, especailly in the left atrium. Irrigated catheters for Stereotaxis's Niobe MNS are awaiting FDA approval. Due to the increased precision of catheter placement, the Niobe system is used mainly for complex procedures. As of January 2007, 6,000 total clinical cases were performed by magnetic navigation, and as of June, 1,000 atrial fibrillation cases (per company press releases). The Niobe has yet to report an instance of perforation during a procedure.

Installing a MNS requires that the catheter lab be equipped with steel plates and specialized equipment to prevent the magnetic fields from interfering with other equipment. Such installations can be costly and time consuming. According to the company, close to 100 units have been installed worldwide, including the Clevand Clinic, UCSF, and several hospitals in Europe, with close to 50 systems in the company's backlog. Due to the cost of the systems ($1.6 million+) and the need to outfit catheter labs for magnetic fields, product adoption has been slow.

Hansen Medical offers a robotic catheter placement device, the Sensei, which claims to have similar advantages as the Niobe without the higher initial capital cost and construction. However, clinical data and disclosures in the company's SEC filings indicate that perforations and safety concerns remain an issue.