Eight complaints involving a device used to filter clots out of the bloodstream has lead Boston Scientific to recall 18,000 Greenfield vena cava filters manufactured before March 10, 2004.
Included in the eight complaints were two involving serious injuries and one involving death.
The device is a cone-shaped steel filter that is installed in a large vein to catch dangerous clots before they are able to reach the lungs. The defect in the product occasionally allows the device to detach before it has been implanted. The filter would then tumble through the bloodstream and eventually cause a blockage itself.
No danger exists in patients who already have the device implanted since the defect was in the delivery system and not in the actual filter. The defect was detected and eliminated by a change in the manufacturing process in March 2004. No recall was issued at that time, however.
In November 2004, a patient died when the device became detached. Again, no recall was issued because the company said it did not know enough about the particular incident. It was a year after the death that Boston Scientific claims to have had enough information upon which to base the recall.
Since the Greenfield filter was first marketed in 1972, some 600,000 have been implanted. Only a small fraction of the recalled devices are expected to be returned. The updated version will remain on the market.
Annual sales of the Greenfield filter amount to some $20 million. To put that in perspective, Boston Scientific’s top product, the Taxus coronary stent, brings in about $3 billion in annual sales.
In addition to the U.S. recall, the company is warning healthcare officials in other countries where the device is marketed about the defect.