Regarding “Clinical course of asymptomatic patients with carotid duplex scan end diastolic velocities of 100 to 124 centimeters per second”

Abstract

I read with great interest the article written by Riles et al1Riles T.S. Lee V. Cheever D. Stableford J. Rockman C.B. Clinical course of asymptomatic patients with carotid duplex scan end diastolic velocities of 100 to 124 centimeters per second.J Vasc Surg. 2010; 52: 914-919Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar regarding the follow-up of 97 asymptomatic patients presenting initially with carotid end-diastolic velocities of 100 to 124 cm/s. The authors should be commended for their efforts to define the natural history of moderate asymptomatic carotid stenosis in a period where endarterectomy is challenged by medical therapy in such cases.2Woo K. Garg J. Hye R.J. Dilley R.B. Contemporary results of carotid endarterectomy for asymptomatic carotid stenosis.Stroke. 2010; 41: 975-979Crossref PubMed Scopus (48) Google Scholar Given their results, the authors conclude, “medical management is appropriate in most cases.” However, two weaknesses of the study should be pointed out: First, as stated by the authors, one of the main current criticisms of large prospective randomized studies (Asymptomatic Carotid Atherosclerosis Study, Asymptomatic Carotid Surgery Trial) that demonstrated the benefit of surgery over medical therapy for asymptomatic carotid disease is that current medical therapy is probably more efficient today than it was 20 years ago, especially because of the generalization of statin use. Therefore, the types of medications administered to the 97 patients during follow-up duration should have been provided to the readers of the Journal of Vascular Surgery because it seems paramount to correctly interpret the results. Second, the authors' conclusion is not supported by their results. The fundamental goal of carotid stenosis management in asymptomatic patients is to prevent ipsilateral stroke and death from neurologic cause with regards to the patient's life expectancy. Although the benefit of medical therapy over surgical intervention in these patients might be real, it needs to be confirmed by studies that include follow-up durations exceeding the usual timing of symptoms occurrence. In the study of Riles et al,1Riles T.S. Lee V. Cheever D. Stableford J. Rockman C.B. Clinical course of asymptomatic patients with carotid duplex scan end diastolic velocities of 100 to 124 centimeters per second.J Vasc Surg. 2010; 52: 914-919Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar mean follow-up was 29.1 months (range, 2-116 months), but ipsilateral symptoms occurred in five patients after a mean of 35.3 months (range, 12-58 months). Of note, three of these five patients experienced symptoms at 54, 54, and 58 months, a follow-up duration that largely exceeded the mean follow-up period of the study. Therefore, it is foreseeable that a higher number of patients managed medically would experience ipsilateral symptoms with a longer follow-up. These patients were not captured by the present study, and this weakens the authors' conclusions regarding the efficiency of medical management in asymptomatic carotid disease. Clinical course of asymptomatic patients with carotid duplex scan end diastolic velocities of 100 to 124 centimeters per secondJournal of Vascular SurgeryVol. 52Issue 4PreviewWith the decline of diagnostic angiography, clinicians increasingly rely upon duplex scan criteria to select appropriate asymptomatic candidates for carotid intervention. Some recent trials have enrolled patients for intervention based upon end diastolic velocities (EDVs) as low as 100 cm/second, and peak systolic velocities (PSVs) as low as 230 cm/second. In as much as we have used more selective duplex scan criteria, we reviewed the course of asymptomatic patients who had EDVs from 100 to 124 cm/second. Full-Text PDF Open ArchiveReplyJournal of Vascular SurgeryVol. 53Issue 1PreviewWe appreciate the comments regarding our clinical study of individuals with moderate asymptomatic carotid stenosis defined by an end diastolic velocity ranging between 100 and 124 cm/sec. I am pleased to respond to the two points made in the letter. Full-Text PDF Open Archive