Magnetism powers cardiac procedure

The first fully automated, magnetically enabled mapping and therapeutic cell injection procedure has been performed in the heart. Results will be presented May 18 at the EuroPCR (Paris Course on Revascularization) 2006 conference in Paris.

The procedure involves the remote magnetic steering of the Stereotaxis Niobe Magnetic Navigation System, the electromechanical mapping features of the Noga XP Cardiac Navigation System for Cordis, and a uniquely designed magnetically enabled injection catheter.

Dr. Emerson Perin, director of new interventional cardiovascular technology at the Texas Heart Institute at St. Luke's Episcopal Hospital in Houston, has performed the procedure remotely from a control room. He mapped the left ventricle, then identified and navigated the magnetic injection catheter to 15 ischemic sites in the left ventricle for targeted injections.

Successful demonstration of the technology clears the way to begin implanting stem cells with unprecedented accuracy in the failing hearts of patients. Work toward this end began in the U.S. as part of a clinical trial approved by the FDA two years ago. The study was based on the theory, still investigational and unproven, that bone marrow cells may stimulate the growth of new blood vessels that will feed and restore the health of ischemic myocardial tissue.

Results from the trial, which was approved for 30 patients, have not been released. The principal goal of the study is to determine the safety of the procedure. Results from a Brazilian study that laid the groundwork for the Texas research were encouraging.

Three years ago, Perin and Texas colleagues, working with staff at Pro-Cardiaco Hospital in Rio de Janeiro, treated damaged human hearts with stem cells taken from the patients' own bone marrow. The patients' improvement surpassed expectations, providing the documentation needed to win FDA approval to begin the trial in the U.S.

The procedure uses a 3D electromechanically derived map of the heart to identify damaged tissue in the left ventricle. Stem cells are then injected along the periphery of the damaged areas. The combined Niobe, Noga, and magnetically driven injector promise to increase reliability and reproducibility. Perin said the combination has the potential to become the new gold standard for injecting stem cells into the heart.

Enhanced control of the catheter tip, possible with the Niobe magnetic navigation platform, provides dramatically faster left ventricular mapping and improved safety and delivery of biologics, according to Stereotaxis. It also allows the mapping and injection to be accomplished remotely, without exposing staff to radiation.