Gear corrosion can occur in motors that are sewn inside patients' bodies.
Medtronic Inc., the world's largest heart device maker, recalled two types of drug infusion pumps after reports that they may fail to properly deliver medicines, leading to a return of symptoms and potentially death.
Medtronic sent an urgent medical device safety notification to doctors on Nov. 9 that the motors may stall on the SynchroMed II and SynchroMed EL pumps. Though the Food and Drug Administration classified the letter as a recall, the machines remain on the market, said Donna Marquard, a spokeswoman for the Fridley-based company.
The pumps are more likely to stall and not properly administer medications when they are used with unapproved drugs, the FDA said Friday in a posting on its website. The failure rate is 2.4 percent when used exclusively with approved drugs, and 7 percent with unapproved medicines after 6.5 years of use, according to an FDA summary. Medtronic and the agency said only approved drugs should be used with the pumps and patients should be closely monitored for return of symptoms.
"The SynchroMed pump continues to demonstrate reliability at or above expected levels," Marquard said in an interview. "We remain confident in its ability to deliver safe and effective therapy to those who need it."
The company isn't aware of any deaths related to the pump and they aren't being removed from the field, she said. The company is investigating the risk of motor gear corrosion, which has been deemed a primary contributor to the pump stalling.
The pumps were manufactured from May 1998 until last month. The risk of corrosion that would cause a motor to stall or seize was first identified in October 2007. There have been 567 complaints about the problem, the FDA said in a July 17 letter.