FDA classifies action as Class I
The U.S. Food and Drug Administration (FDA) has classified Medtronic’s recent voluntary recall of its HeartWare HVAD System as Class I, which the agency defines as “a situation in which there is a reasonable probability that the use of or exposure to a violative product will cause serious adverse health consequences or death.”
Medtronic (Dublin, Ireland) stressed in its news release Friday that “there have been no confirmed reports of catastrophic harm” associated with the recall, which the company issued because of “unexpected power source switching.”
The recall affects 16,399 HeartWare Ventricular Assist Device (HVAD) Systems implanted as of May 22, Medtronic said.
“In a notification letter distributed in May 2018, Medtronic alerted clinicians worldwide about a potential transient interruption of the electrical connection between a HeartWare HVAD System power source and the HVAD Controller, which results in unintended switching to the device's secondary power source and could cause the System to momentarily stop and restart,” the company’s news release says. “In addition, unintended power switching can result in unexpected audible tones (‘beeping’). This beeping, which occurs when the electrical connection interruption automatically resolves, may confuse the patient or caregiver, as the Controller may display sufficient battery capacity or AC/DC connectivity at the time of the audible tone. Also, a Critical Battery Alarm may be momentarily incorrectly displayed due to this phenomenon.”
In a MedWatch Safety Alert issued Friday, the FDA said the interruption in power “is caused by oxidation on the connecting surfaces between the power source connector and the controller’s power source socket.” These interruptions could result in intermittent electrical disconnection, which could lead to a pump stop, the agency said.
“A pump stop could cause patient harm such as exacerbation of heart failure symptoms, or symptoms such as mild weakness, dizziness, anxiety, nausea, loss of consciousness, or death,” the FDA said.
The company recommends that clinicians:
- Emphasize that patients always ensure that two power sources (AC or DC adapter plus battery or two batteries) are connected at all times except when changing a power source,
- Reinforce that patients connect a fully charged battery to the device and then connect the AC adapter when going to bed and ensure that they connect two fully charged batteries when waking up in the morning, and
- Instruct patients to report any “persistent, unexpected audible tones” to the VAD team for additional instructions.
Medtronic made available a lubricant solution that can be applied to the HVAD power source connection as a way to mitigate unexpected transient power switching. HeartWare field representatives are distributing the lubricant, the company said.
The HVAD System is indicated for use as a bridge to cardiac transplant in patients at risk of death from end-stage left ventricular heart failure, according to the FDA. The device functions as a pump that helps the heart deliver blood to the rest of the body.