The FDA has issued an update on Medtronic’s June 28 recall of its HeartWare Ventricular Assist Device (HVAD) system batteries, deeming it a Class 1 recall because of the risk of serious injury and death.

The HVAD system, which is designed to help the heart to pump blood, operates with power from either AC or DC electricity or batteries. Medtronic recalled the batteries because of a risk that they could fail and potentially cause the HVAD pump to stop.

The device is used as a bridge to cardiac transplants in some patients or as a destination therapy — as opposed to a transitional therapy — in patients who will not receive a heart transplant.

The 23,372 affected products were distributed from Jan. 1, 2009 to the time of the recall.

There have been 1,159 complaints, six injuries and one reported death related to this issue so far, the FDA said.