The treatment and follow-up of patients with carotid artery stenosis

Dear Editor,

We have read the article by Yılmaz et al. 1 entitled “In-stent restenosis estimation following carotid artery stenting: The robust predictive value of atherogenic index of plasma and other non-traditional lipid profiles” with great interest. First of all, we congratulate the authors for their good contribution. However, we would like to discuss some issues about the treatment and follow-up of patients with carotid artery stenosis.

In their single-center retrospective study, the authors included 719 consecutive patients who underwent carotid artery stent (CAS). ¹ They analyzed the factors affecting the development of restenosis during 2-year follow-ups. Restenosis occurred in 29 (4%) patients. Doppler ultrasonography (DUSG) was primarily used in the diagnosis of restenosis, and angiography was performed in suspicious patients. ¹ However, it should not be forgotten that ultrasonography is an operator-dependent imaging method.^2,3 Therefore, some diagnoses may be missed, especially in retrospective follow-up studies. The fact that the physician who performs the DUSG evaluation immediately after the CAS procedure is the same as the physician who performs the follow-up evaluations may be valuable in these studies.

In the study, the authors analyzed the baseline values of laboratory and clinic parameters. Accordingly, it is understood that approximately 40% of patients did not use statins. ¹ Has there been any change in the patient’s statin usage during the 2-year follow-up after the CAS procedure? It is also obvious that the atherogenic index value may be affected by statin use and the type of statin used. ⁴ In addition, the relationship of parameters obtained from routine blood values to a current event can be easily evaluated.^5,6 However, it should not be forgotten that blood lipid values may change in long-term follow-up studies.

Diabetes mellitus (DM) affects the development of cardiovascular diseases and is a very important prognostic factor. ⁷ In their study, the authors found the rate of DM to be similar in patients who developed restenosis and those who did not (50% vs 42.4%, p = .409). However, in multivariate analysis Model 2, DM was found to significantly increase the risk of restenosis (odds ratio = 3.75, p = .043). ¹ What do the authors think about this situation? In addition, it should not be ignored that changes in blood glucose values may have an impact on prognosis in long-term follow-up studies.

Finally, the authors did not include patients with non-atherosclerotic disease (cerebral arteritis, etc.) to whom they applied CAS in their study. ¹ However, CAS applications in patients with arteritis are a very controversial issue.^8,9 How many patients with arteritis underwent CAS in the current study dates (2016-2020)? What are the authors’ clinical protocols in these applications?