Background: The Niobe Stereotaxis system consists of two 0.8 Tesla magnets and a navigation software allowing to move specially designed coronary wires.
Aim: The aim of this observational multicenter study was to systematically evaluate the capability of the Stereotaxis Niobe Magnetic Navigation system to facilitate wire navigation during percutaneous coronary intervention (PCI), to determine the success rate of magnetically guided PCIs in a real-world setting, and to analyze procedure-related variables influencing the outcome data.
Methods: One hundred and fifty seven patients underwent magnetically guided PCI in three German centers. Demographic variables of the patients, lesion quality determined by quantitative coronary angiography, success rate of the procedure as well as radiation time were analyzed. A subanalysis was performed for two periods (06/04-10/06 and 10/06-10/07) owing to a second generation of wires which was introduced at the beginning of the second period and procured-related learning curves of the operators.
Results: Mean age of the patients was 65 +/- 0.4 years (82% male, 18% female). 25% of the patients were diabetics. The lesions were characterized by high complexity (11% AHA type A, 25% type B1, 38% type B2, 25% type C). Mean percent lesion stenosis was 83.7 +/- 11.9%. The total fluoroscopy time was 13.2 +/- 0.3 min and the fluoroscopy time to cross lesion was 90.4 +/- 62.2 s. The overall success rate of the magnetically guided approach was 89%. All failures occurred within the first period were. In these cases, 80% of the failures could be successfully treated after switching to the conventional wires. On the other hand, between 10/06 and 10/07 three conventional PCI failures could be successfully treated using the Stereotaxis system.
Conclusions: Magnetically guided PCI represents a promising tool for the treatment of dedicated lesions. There is a marked difference in the success rates of the method between the two different time periods which were analyzed, reflecting advances in the wire development and learning curves of the respective operators. Randomized controlled trials are required to determine the method's overall value and to identify subgroups that may particularly benefit.