Tapan Mehta, MBBS, MPH
In this entry, I discuss a recent publication by Dr. Jeong-Ho Hong and colleagues regarding effectiveness of statin pretreatment on preventing the periprocedural complications of carotid artery stenting (CAS).
CAS as a procedure has evolved significantly in the past two decades. Previous studies have shown increased periprocedural complication risk with CAS compared to carotid endarterectomy (CEA). Invention of new endovascular devices, distal embolization protection systems and antiplatelet medications, along with increasing operator experience, have contributed in reduction of periprocedural complications. Recently published CREST trial data can be considered an important example of this. As there is already data available on statin pretreatment reducing periprocedural complication risk for CEA and percutaneous coronary intervention, this study importantly extends the possibility of benefit with pre-procedural statin use for patients undergoing CAS.
The study population with symptomatic carotid disease within 180 days of CAS was collected retrospectively from a prospective CAS registry of 2 tertiary university hospitals, between July 2003 and June 2013. Patients with recent stroke who were at higher risk for hemorrhagic transformation and life expectancy less than a year were excluded. Self-reporting or hospital record review ascertained the statin name and dose. Patients were accordingly categorized into no-statin, standard-dose (≤40 mg), and high-dose statin groups (> 40 mg) according to the atorvastatin-equivalent dose, based on the lipid reduction fraction at the time of CAS, independently of the duration of therapy. Periprocedural complications were defined as the composite outcome of any stroke, myocardial infarction, or death because of any cause during or within 1 day after the CAS procedure (immediate procedural events) and 1 to 30 days after the procedure (30-day clinical events).
397 CAS cases were enrolled, of which 239 cases (60.2%) received statins; atorvastatin was the most commonly used statin (n=191; 80.0%). There were 39.8% cases in the no-statin, 39.0% in the standard-dose, and 21.1% in the high-dose groups. Urgent carotid stenting was performed in 43 cases (10.8%), and the proportion of acute carotid stenting did not differ among the 3 groups. Similarly, there was no statistically significant difference in lipid profile among the three groups. Statistically significant higher prevalence of hypertension, dyslipidemia and ischemic heart disease was noted in the high-dose statin group. It is important to note that 93% no-statin group and 98.1% standard dose statin group received pre-stenting antiplatelet medication, compared to 100% in the high-dose group (p<0.008). The authors included pre-stenting antiplatelet use, pre-stenting statin use, sex, hypertension, ischemic heart disease, hyperlipidemia, the quartile of recruitment, and statin pre-treatment as co-variates in multivariate logistic regression analysis for the outcome of periprocedural complications. In addition to statin pre-treatment being an independent predictor of reduced periprocedural risk, there was a linear trend effect of the statin dose (standard-dose statin: odds ratio (OR) 0.24; 95% Confidence Interval (CI) 0.07−0.81; high-dose statin: OR 0.11, 95% CI 0.01−0.96; P for trend=0.01). The antiplatelet pre-treatment was also an independent predictor of lower pre-procedural complication risk (OR 0.18, 95% CI 0.05–0.69, p = 0.01).
The study shows an important association of statin use before CAS with a reduction in periprocedural complication rate in a dose dependent manner. Despite limitations due to the retrospective nature of the study with a relatively long 10-year duration, the association shown by the authors is very important and warrants further prospective clinical trial to show causation. In the era of overall similar efficacy of CAS and CEA for symptomatic carotid disease, appropriate procedure selection based on patient profile and understanding of predictors of complications and good outcomes is pivotal.