CRT-D May Cause The Pacemaker To Stop Working. A battery defect with some St. Jude Medical implantable cardioverter defibrillators (ICD) and cardiac resynchronization therapy defibrillators (CRT-D) may cause the pacemaker devices to stop working sooner than expected. These heart devices are implanted in the upper chest area and connected to the heart through insulated wires. In patients with a slow heart rhythm, they provide pacing. In patients with an abnormally fast heart rhythm, they provide electrical shocks or pacing.
The U.S. Food and Drug Administration (FDA) warned that in some devices, the lithium-based battery is prone to early depletion. As such, the agency is urging patients and healthcare providers to address elective replacement indicator (ERI) alerts immediately. Under normal circumstances, the battery will last another three months after the ERI alert goes off. According to the FDA safety communication however, there have been reports of the battery losing power within 24 hours of the ERI alert.
The Defect Is Caused By Lithium
The battery defect is caused by a buildup of lithium. These so-called “lithium clusters” can cause a short-circuit, draining the battery quickly. If the battery undergoes premature depletion, the ICD or CRT-D will be unable to provide shocks or pacing, which could result in death.
Out of 398,740 devices sold worldwide, 841 have been returned for analysis due to premature battery failure. Two patients died when the devices were unable to provide life-saving therapy. Battery depletion was also implicated in 10 cases of patients fainting and 37 reports of dizziness.
The ERI alerts should be programmed to vibratory mode. Patients are also advised to use the St. Jude Medical’s home monitoring system to monitor battery status. Removing the pacemakers comes with its own complications and risks, so monitoring is recommended for most patients.
In some cases, the ERI alert may not be detected before the battery depletes. Therefore, monitoring may be inadequate in these patients. Physicians should determine whether or not it is appropriate to replace a device.