TGA Halts Study on St. Jude Medical Nanostim Leadless Pacemaker

Australia’s TGA has issued a warning and halted a clinical study of St. Jude Medical’s Nanostim leadless cardiac pacemakers due to battery malfunctions.

The pacemakers were implanted in 22 Australian patients as part of the Nanostim Leadless II IDE/CAP clinical study, which has been halted. The company reported that 0.5 percent of the implanted Nanostim leadless cardiac pacemakers have experienced battery malfunction.

The study was being conducted at 56 centers in the U.S., Canada and Australia. To date, 1,423 devices have been implanted worldwide, according to St. Jude Medical.

There have been seven reports of patients participating in the study who experienced loss of telemetry and pacing. Each of those cases occurred more than two years after implantation. No injuries were reported. Symptomatic bradycardia was identified in one patient, St. Jude Medical said.

The other six patients were asymptomatic, and the device malfunctions were discovered during routine scheduled follow-up visits. The company said that no injuries were reported.

According to an analysis of the first 300 patients in the study, serious adverse events were observed in 6.7 percent of patients in the primary analysis cohort at six months post implantation. Those events included device dislodgement, cardiac perforation and pacing-threshold elevation. An FDA advisory committee said that those results provided reasonable safety assurance.

Leadless cardiac pacemakers, like standard pacemakers, deliver electrical impulses to treat slow heart rate. Unlike a standard pacemaker, a leadless cardiac pacemaker is implanted into the patient’s heart via a catheter into the right ventricle and does not require a pacing lead, connector, or pulse generator pocket.

Read the TGA safety notice here: www.fdanews.com/12-02-16-StJudeAustralia.pdf. — Tamra Sami