St. Jude Medical, Inc. (NYSE:STJ), a global medical device company, today announced the first enrollments in the company’s LEADLESS Pacemaker Observational Study evaluating the Nanostim™ leadless pacing technology. The Nanostim pacemaker received CE Mark in 2013, and post-approval implants have occurred in the UK, Germany, Italy, Czech Republic, France, Spain, and the Netherlands.