Assessing Impact of High-Dose Pitavastatin on Carotid Artery Elasticity with Speckle-Tracking Strain Imaging

Abstract

Aim: Speckle-tracking imaging has been introduced for the precise assessment of vessel mechanics. However, there are no data on the role of this imaging tool in assessing the changes in vasculature with statin therapy, which is known to enhance vascular elasticity.

Methods: This study was a prospective study including 48 statin-naïve patients (age, 58.2±8.4 years; 29.2% male) with hypercholesterolemia. Circumferential carotid artery strain (CAS) and stiffness index (β₂) were measured using speckle-tracking imaging before and after 3 months of high-dose pitavastatin treatment (4 mg daily). For the comparison, we measured conventional carotid elasticity parameters and intima-media thickness using B-mode ultrasound at the same time points.

Results: Compared with baseline, there was significant improvement in circumferential CAS (2.98%±1.18% to 3.40%±1.43%, p=0.008) and β₂ (0.19±0.07 to 0.17±0.08, p=0.047) after statin therapy. Contrariwise, there were no significant changes in all conventional carotid elasticity metrics and intima-media thickness. When stratifying patients into two subgroups by 10 year atherosclerotic cardiovascular disease (ASCVD) risk, speckle-tracking-derived circumferential CAS and β₂ improved significantly only in patients with ASCVD risk ≥ 7.5%.

Conclusions: Short-term treatment with high-dose pitavastatin improved carotid artery elasticity measured by speckle-tracking method, but not conventional parameters by B-mode ultrasound. Speckle-tracking-based measurements may allow the early noninvasive assessment of statin effects on vascular function in hypercholesterolemic patients.

Keywords: Carotid artery elasticity; Carotid artery strain; Hypercholesterolemia; Pitavastatin; Speckle-tracking imaging.

Fig. 1.

Flowchart of study subjects

Fig. 2.

Representative examples of measurements of CAS by speckle-tracking imaging

Fig. 3.

Plot of individual changes in carotid ultrasound variables by statin The individual changes in circumferential CAS (A), stiffness index (β₂) (B), strain by B-mode ultrasound (C), and mean carotid IMT (D) after high-dose pitavastatin therapy. The dots and bars on the sides indicate means and standard deviations. CAS, carotid artery strain; IMT, intima–media thickness.

Fig. 4.

Plot of individual changes in speckle-tracking-derived carotid artery elasticity parameters according to 10 year ASCVD risk Note significant improvements in circumferential CAS and β₂ by speckle-tracking imaging in patients with ASCVD risk ≥ 7.5% (A and B), which are not observed in patients with ASCVD risk <7.5% (C and D). The dots and bars on the sides indicate means and standard deviations. CAS, carotid artery strain; ASCVD, atherosclerotic cardiovascular disease.

Supplemental Fig. 1.

Plot of individual changes in speckle-tracking-derived carotid artery elasticity parameters according to baseline LDL-C levels Note the effect of statin treatment on improvements in circumferential CAS and β₂ was pronounced in patients with baseline LDL-C levels ≥ 190 mg/dL. CAS, carotid artery strain; LCL-C, low-density lipoprotein cholesterol.

Fig. 5.

Bland–Altman analysis for circumferential CAS measurement Bland–Altman plots of intraobserver (A) and interobserver variabilities (B) for measurements of circumferential CAS by speckle-tracking method. The solid line is the mean difference between the two scans, whereas the limits of agreement are drawn as dashed lines (mean difference ± 2 SD). CAS, carotid artery strain; SD, standard deviation.