Editorial Comment—With or Without Protection? The Second Important Question in Carotid Artery Stenting
This is already the second editorial comment within the last 6 months about protection devices in carotid artery stenting.1 Obviously, this seems to be an important question. In the August issue of Stroke, Cremonesi and co-workers reported about their experience with these protection devices and suggested that the use is feasible and effective, but not without complications.2
And now, in this issue, the EVA-3S Trial committee reports the comparison of protected and unprotected stenting procedures.3 Due to the better results when using protection devices, the safety committee recommended stopping unprotected stenting within the study.
From a scientific point of view, this recommendation was not absolutely necessary. A substantial number of patients treated without protection developed a stroke, not during the procedure but during the first 30 days. And this cannot be related to the nonuse of a protection device! However, this is a large randomized study and the reviewers and the editorial board of Stroke decided that the preliminary results have to be published! But, the publication of these results (or should I say, “of this opinion”?) should not be used to change all “stenting” procedures into “stenting with protection” procedures. They should be seen as part of a growing data pool, which it is hoped will allow us one day to make a definite decision based on real evidence. This report is clearly a piece of a puzzle and absolutely not the final proof for the protecting devices. The number of patients treated, the number of complications, and the type of complications (delayed stroke) are not powerful enough to convince. But anyhow, this important decision of the safety committee cannot be ignored by the neurovascular community and should be discussed extensively.
I suggest that the steering committees of the Stent-protected Percutaneous Angioplasty of the Carotid vs Endarterectomy (SPACE) study (Germany) and Carotid and Vertebral Artery Transluminal Angioplasty Study 2 (CAVATAS 2; United Kingdom) should do an interim analysis with a focus on the difference between “protected” and “non-protected” patients as soon as the number of patients is powerful enough. We all know that protection devices are not free of complications and it is still questionable whether the latter is really outbalanced against the advantages.
Eckert and Zeumer1 nicely pointed out that the current data indicate that protected carotid artery stenting has a combined stroke and death rate of 2.0%, whereas that of unprotected carotid artery stenting is 3.2%. However, if it turns out that this difference is true for larger study cohorts, we clearly have to use these devices. To analyze the complications, the learning curve, and at what point of the learning curve the protection devices game into game might be of major importance. If we—at our institution—would start with protection devices tomorrow, it might be that the protected results would be better than the unprotected stenting results from the past 2 years—but probably not really related to the protection, but mainly related to our improved skills and our increased experience with different anticoagulation regimens. To conclude, at our institution we will continue not to use the protection device. From a medicolegal point of view, scientific data still allow us to do the procedure both ways. But we have to be aware and we encourage all investigators to keep their eyes—at least one—on that problem. Coming back to the title: do not forget that we still do not have evidence that stenting is better than surgery. And this is clearly the most important question to answer.
Eckert B, Zeumer H. Carotid artery stenting with or without protection devices? Strong opinions, poor evidence! Stroke. 2003; 34: 1941–1943.
Cremonesi A, Manetti R, Castriota F, Setacci F, Setacci C. Protected carotid stenting: clinical advantages and complications of embolic protection devices in 442 consecutive patients. Stroke. 2003; 34: 1936–1943.