St. Jude calls for retraction of Hauser et als study on lead failures
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The analysis, titled, “Deaths Caused by the Failure of Riata and Riata ST Implantable Cardioverter-Defibrillator Leads,” published March 26, assessed the number of death reports associated with St. Jude’s Riata and Riata ST defibrillation leads compared with Medtronic’s Quattro Secure leads, based on a search of the FDA’s Manufacturers and User Facility Device Experience (MAUDE) database. In the analysis, the authors classified the deaths in one of three categories (lead related, indeterminate or not lead related) and drew conclusions about how Riata and Riata ST leads compare with Medtronic’s Quattro Secure leads.
“Using the same search criteria outlined in the manuscript,” St. Jude said it has identified that Hauser’s research “substantially undercounted total deaths in the MAUDE database for Quattro Secure, which therefore resulted in substantial errors related to how Riata and Riata ST leads compared to the Quattro Secure lead.”
St. Jude said its independent search of the MAUDE database found 377 reports of deaths involving Quattro Secure leads, not 62 as stated by Hauser et al in the published study. The St. Paul, Minn.-based company also said that its analysis of Riata and Riata ST lead events found in the MAUDE database indicated that Hauser did not report an additional three deaths, which would change the number from 71 in Hauser’s study to 74.
In the study's methodology, Hauser et al defined a lead-related death as a sudden or unexpected death accompanied by evidence of a lead defect; an indeterminate death was a death that was either non-sudden or the circumstances were unclear or evidence of a lead defect was not provided; a not lead-related death was a death that was non-sudden or expected for reasons related to the patient’s health status and/or there was no evidence that the lead’s performance contributed to the patient’s demise.
The study authors also wrote that "deaths due to perforation or occurring during or as the result of a lead extraction procedure were considered indirect causes of death, and therefore not lead-related."
Hauser’s study is “mistaken or misleading in a number of other respects as well," according to St. Jude's public statement. "It is important to note that Hauser has selectively chosen to include only one Quattro Secure lead model in his analysis versus all of the Riata and Riata ST models for St. Jude Medical. Although we did not include those lead models in our analysis, there are also deaths associated with those additional model numbers.”
Finally, St. Jude said the “entire premise of the comparison of a recalled silicone-only insulated lead versus Quattro Secure, which is a product insulated with a polyurethane outer insulation, is flawed. It is acknowledged in the industry that silicone-insulated leads are more susceptible to abrasion than leads with newer insulation materials. A more appropriate comparison would have been to compare the Riata and Riata ST leads to other recalled leads.”
Addressing this issue in the study, Hauser et al wrote, "These multilumen silicone leads are prone to a unique inside-out insulation defect caused by movement of the conductor cables within their lumens. While much interest has been directed toward externalized conductors, it is an electrical malfunction, such as failure to pace or defibrillate, that poses the greatest risk to patients."
In response to this independent study, Medtronic spokesperson Christopher Garland told Cardiovascular Business that “St. Jude’s press release appears to be nothing more than a dispute between St. Jude and Hauser. However, over the weekend, Medtronic reviewed the MAUDE filings on Quattro as described in Hauser’s report, and has followed his criteria as outlined in his article. To that end, the conclusions we have reached about Sprint Quattro are consistent with what Hauser found, and we confirm his results related to Sprint Quattro.”
In addition, St. Jude said it was not consulted prior to the publication, nor asked to validate any of the data against its returns analyses. Since the study was published, the company said it has spent more than 300 hours attempting to reach the same conclusions as Hauser, “but can find no way of analyzing the MAUDE database that reproduces the same numbers reported in the manuscript.”
“Given these factual errors and biased analysis,” St. Jude is “requesting that the manuscript immediately be retracted by the authors and removed from online publication by the official journal of the HRS.”
As of press time, HRS did not respond with a comment or issue a formal statement about St. Jude's independent study.