UPDATED: St. Jude recalling some defibrillator leads due to damaged insulation

Optisure defibrillator lead--Courtesy of St. Jude Medical

St. Jude Medical ($STJ) is still smarting from the permanent recall of its Riata defibrillator leads in 2010, following reports of injuries and a handful of patient deaths from the faulty defibrillator wires, whose insulation wore off far faster than anticipated. Last year, the company agreed to pay $14.25 million to settle 950 pending legal claims related to the component. So news of a Class 1 recall of 447 Optisure defibrillator leads due to a manufacturing defect that may have introduced damage to the wires' insulation is rather unsettling.

The good news is that the problem doesn't appear to be as widespread this time around. St. Jude sent doctors a recall letter in November informing them that company discovered "that during the manufacturing process of a limited number of Optisure leads, a trim technique to remove excess medical adhesive around the SVC shock coil may have introduced damage to the lead's insulation," according to a post in the FDA's recall database. Almost two-thirds of the affected units are in the U.S.

The agency classified the recall as Class 1, a designation that is reserved for situations in which the use of the faulty devices may cause serious injury or death.

"Depending on device programming and the depth of the inadvertent cut to the insulation, compromise of lead insulation can potentially lead to an electrical malfunction wherein the defibrillator cannot deliver appropriate high voltage therapy," St. Jude explains in a release. 

In the recall letter, which is made public by Germany's Federal Institute for Drugs and Medical Devices, St. Jude says it is not aware of any adverse events related to the manufacturing defects. The company estimates the probability of a high voltage short resulting from the insulation damage to be 0.32%.

But the company is not asking doctors to return the affected leads, and a replacement is unlikely to be needed in the vast majority of cases. 

St. Jude advised doctors ensure all potentially affected patients are enrolled in its web-based Merlin.net patient monitoring platform, and use a technology, dubbed DynamicTx, that "automatically adjusts shock configurations to ensure the delivery of high-voltage therapy even if an electrical short were to occur," according to the recall letter. All but 9 patients with the affected leads have devices with the DynamicTx feature, St. Jude said in a release.

For patients with an ICD or CRT-D without DynamicTx, a lead replacement should be considered based on the results of certain tests, the letter says. St. Jude said in its release that all 9 patients whose device does not have DynamicTx have been contacted and informed of the situation.

The notice in the FDA's recall database contains additional information to assist in the identification of the affected devices that are subject to the recall.

The recall occurs as St. Jude ICDs and pacemakers lose market share in the U.S. due to a lack of approved, MRI conditional low-voltage devices. Quarterly sales of cardiac rhythm management devices fell 10% year over year to $580 million.

- here's more from the St. Jude release 
- read the recall letter to doctors
- here's more information in the FDA's recall database

Editor's Note: This article has been updated with information from a St. Jude release.