Response to Letter by De Rango et al
I agree with De Rango et al that the verdict is “still pending” as to whether carotid artery stenting (CAS) is equivalent or even better than carotid endarterectomy (CEA) in low surgical risk patients or better than medical therapy in high surgical risk patients. The key point is that CAS is not proven effective yet for either patient population. In no way was CAS judged inferior. It is simply unproven.
We differ on the application of this information for the treatment of patients with asymptomatic carotid stenosis. Our first responsibility to our patients has always been to do no harm, ie, primum non nocere. At present, there are no data from randomized trials to show that CAS provides any benefit to any asymptomatic patient. Furthermore, it may be harmful. This may be particularly true in the high surgical risk patients, given the results of the SAPPHIRE trial. In addition, patients with low surgical risks already have a proven benefit with CEA. Routine use of CAS in this population is clearly not appropriate. There are ongoing clinical trials that are aimed at providing this information and we are obligated to support them.
Most of the specific issues raised by the authors are largely valid and I do not argue them here, because none affects the strength of the original conclusion as stated. It is true that we have limited information regarding the risk of CAS in low surgical risk patients. The definition of high surgical risk may be subjective, both for anatomic and coexisting medical problems. Whether contralateral carotid occlusion is a risk factor for future stroke is controversial. Nevertheless, we have a proven effective therapy for low surgical risk patients (CEA). It is not ethical to substitute CAS for CEA in this population until CAS is proven equivalent. Furthermore, the current data for CAS and CEA in high surgical risk patients suggest that there may be no benefit of either procedure in this population. The verdict is still pending. Consequently, the use of this procedure in asymptomatic patients should be limited to studies designed to provide us the answer to these questions.
C.P.D. is on the Scientific Advisory Board for W.L. Gore and Associates, and has received honoraria from Boston Scientific Corporation/Target Therapeutics.