Patients Hurt by Deceit in Bjork Shiley Valve Approval

San Diego, CAWhen Donald P. Shiley, co-inventor of the Bjork Shiley Heart Valve died in 2010, the Los Angeles Times (8/7/10) covered his death. Shiley had suffered failing health not related to the Bjork Shiley heart valves that he helped create. But the Los Angeles Times article noted that fewer than 10 years after the valve was approved for sale, the US Food and Drug Administration (FDA) forced a Bjork Shiley valve recall.

The recall was announced following concerns that the Bjork Shiley valve was seriously flawed, causing fatal adverse events in patients. Furthermore, the FDA conducted an investigation into Pfizer, who had purchased Shiley Laboratories, for allegedly withholding information about the risk of flaws in the valves. Following the investigation, the FDA reached a $20 million settlement with Pfizer regarding the Bjork Shiley heart valves.

The Bjork Shiley heart valves were approved by the FDA in 1979, but were withdrawn from the market in 1986. The reason for the recall was that the outlet strut reportedly developed fractures due to welding problems. According to a report by Brown University (biomed.brown.edu; 2007), one end of the strut usually fractured first, and within a few months, the other end would also fracture.

"Fracture occurred from brief impacts on the outlet strut connections due to over-rotation of the disc closing with almost ten times the force of the disc opening," the Brown report notes. "This created bending stresses beyond the strut's fatigue endurance limit that eventually caused fatigue-induced fracture after many occurrences of outlet tip overloading."

Once the valve failed, the disc became free of the valve, preventing the valve from regulating blood flow. If the problem was not detected and resolved in time, the patient could die.

Brown notes that fractures of the valve occurred during premarket trials and were thought to be the result of welding problems, but Shiley told the FDA that the failures were flukes and the number of people who would benefit from the valve was far greater than those who were at a very small risk of outlet strut fracture. The FDA reportedly approved the device, trusting that the company in charge of the valves would report failures, but Pfizer allegedly restricted the release of negative reports to the FDA, allowing the struts to continue to be implanted.

According to Brown, of 500 cases of fracture reported, two-thirds resulted in death.