The Washington Post is reporting on recent findings in the New England Journal of Medicine highlighting an increased risk of strokes due to emboli, in patients implanted with carotid stents, which runs contrary to previous knowledge. Apparently, the critical detail in the new methods was the failing to use the downstream umbrella-like filter devices used to catch clots that might originate at the location of the stent…
In the new study, French researchers recruited adult patients who had symptoms, a 60 percent or more blockage of the carotid artery, and an average surgery risk. Of the 520 participants, half got surgery and half got stents.
A month after undergoing the procedures, nearly 10 percent of the stented patients suffered death or stroke, versus only 4 percent of the surgical patients.
In contrast, a 2004 U.S. study of patients with high surgery risk found the incidence of death, stroke or heart attack was about 5.5 percent in patients treated with a stent and 10 percent in patients treated with surgery. The difference was attributed to fewer heart attacks in the stent patients.
Some doctors criticized the new study. They noted that initially, the physicians who placed stents did not use an umbrella-like device that is placed beyond the blockage to catch any plaque that breaks off. The 2004 study used the devices.
There you have it…evidence that experimental design is critical. When your tactics don’t reflect the current state of clinical treatment, you risk finding out just how important those little details can be.
More from the original article by Mike Stobbe…