Federal regulators this week upgraded the recall of Medtronic's HeartWare Ventricular Assist Device to a Class 1 recall, its most serious classification.
Under the recall, the Food and Drug Administration (FDA) warns that "use of these devices may cause serious injuries or death."
Medtronic stopped selling the device, also known as HVAD, last summer as mounting clinical evidence indicated a higher rate of stroke and death among patients using the product compared with similar devices.
About 3,800 patients still have the Medtronic device implanted. The latest action recalls more than 1,600 of them.
The HVAD was designed for patients with severe heart failure; its mechanical pump was designed to increase blood flow through the body.
This year, a welding defect was disclosed that could cause the pump to rotate incorrectly. Patients with those devices might show symptoms akin to pump thrombosis, which is a blockage in the flow of blood through a vessel.
"The well-being and experiences of patients implanted with the HVAD pump are vitally important to us," said Erika Winkels, a Medtronic spokeswoman.
"Although Medtronic no longer distributes the HVAD system, we are committed to ongoing quality assessments and control measures to further patient safety and therapy effectiveness."
