MN Med-Tech Cos. Dispute New Heart Device Study
A new study suggests that medical devices designed to keep patients' hearts beating properly may not help about 40 percent of patients who are currently eligible for the devices.
Fridley-based Medtronic, Inc., and Little Canada-based St. Jude Medical, Inc.-both leading makers of the devices-disagree, contending that the guidelines used to determine whether patients should receive the devices were established using credible clinical trials and should be maintained.
The new study, published by the Archives of Internal Medicine, examined the effectiveness of cardiac resynchronization therapy (CRT) in patients with heart problems. CRT devices resynchronize patients' heartbeats by delivering electrical impulses.
Guidelines have been developed to determine whether patients should be considered candidates for the treatment, based in part on a measurement called a QRS duration, which is read by an electrocardiogram (ECG). Current guidelines recommend that patients with a QRS duration of 120 milliseconds or longer may be eligible for the devices.
But Ilke Sipahi- associate director of heart failure and transplantation at University Hospitals Case Medical Center in Cleveland and author of the study released Monday-said that an analysis of several randomized trials revealed that patients with QRS durations shorter than 150 milliseconds did not benefit from CRT treatment.
According to Sipahi's study, roughly 40 percent of CRT devices are implanted in patients with QRS durations of between 120 and 150 milliseconds. That means, if the study's findings are accurate, four out of 10 patients with CRTs may not benefit from the devices.
Medtronic, Inc., wrote in an e-mail to Twin Cities Business that multiple studies have suggested that CRT benefits are greater for patients with QRS durations longer than 150 milliseconds, as confirmed by Sipahi's study. But the company said that it disagrees with the findings that patients with QRS durations of between 120 and 150 milliseconds don't benefit from CRT.
“Multiple, robust, prospective randomized clinical trials were conducted to establish the current treatment guidelines, which cannot be discounted,” the company said, adding that “meta-analyses” like the one detailed in Sipahi's study “have value limitations, and thus should not be looked to for treatment guideline decisions.”
St. Jude issued a statement echoing similar concerns. It said that the study “looks at CRT through a narrow lens.” The company points out that when Sipahi's study describes “benefits” of CRT, it is focused only on whether the device prevents death or hospitalizations and does not account for the effect on patients' symptoms or quality of life. St. Jude also said that “meta-analyses can be interesting and raise new hypotheses, but should not be given equal weight as randomized clinical trials to determine policies or treatment guidelines.”
A report by the Wall Street Journal indicates that CRTs are implanted in about 60,000 heart patients each year, and the devices typically cost $25,000 or more.
“To continue to perform this procedure when benefit is unlikely will undermine enthusiasm for a remarkably effective therapy in appropriate patients,” Lynne Stevenson, a heart-failure expert from Brigham and Women's Hospital in Boston, wrote in a letter published on the Archives of Internal Medicine Web site. “It may have been optimistic to recommend and reward this procedure in patients for whom there was no evidence of benefit; it may now be unethical to recommend and reward this procedure in patients for whom we now have evidence of no benefit.”
In addition to Medtronic and St. Jude, Natick, Massachusetts-based Boston Scientific-which maintains a significant work force in Minnesota-also is a leading producer of CRT devices.