Effect of Low- and High-Dose Atorvastatin on Carotid Artery Distensibility Using Carotid Magnetic Resonance Imaging - A Post-Hoc Sub Group Analysis of ATHEROMA (Atorvastatin Therapy: Effects on Reduction of Macrophage Activity) Study

Aim: To assess the effect of low- (10 mg) or high- (80 mg) dose atorvastatin on carotid artery distensibility in patients with asymptomatic carotid artery disease using carotid magnetic resonance imaging. Methods: Eighteen patients underwent initial 2-dimensional ECG gated-phase contrast carotid MR imaging and off-line applanation tonometry for distensibility assessment before randomisation to receive low-or high-dose statins and this was repeated at 12 weeks. Phase and magnitude images from the 2-D phase contrast acquisitions were used for quantification of distensibility and compliance coefficients and were compared between the low-and high-dose statin groups. Results: Both groups were comparable with regards to their demographics, co-morbidities and baseline cholesterol levels. After 12 weeks of high-dose statin administration, a significant decrease in LDL (p=0.003) and CRP (p=0.03) was observed. At 12 weeks, the distensibility coefficient of the common and internal carotid artery was found to be significantly higher (with respect to baseline) in the high-dose group (p=0.004 and p=0.007, respectively). The compliance coefficient was likewise found to be raised in the high-dose group when compared with the low-dose group [common carotid (p=0.002), internal carotid (p=0.009)]. Conclusions: High-dose atorvastatin tends to reduce carotid arterial stiffness, as suggested by increased distensibility and compliance coefficients; however, these results need validation through large-scale trials to fully establish their possible use in clinical practice.