Effect of rosuvastatin on atherosclerotic plaque stability: An intravascular ultrasound elastography study

- Rosuvastatin stabilizes the mechanical properties of atherosclerotic plaques in rabbits.
- The shoulder of eccentric plaque develops faster than the body region into a rupture-prone site.
- Rosuvastatin keeps the shear and area strain of the plaque shoulder region at a low level.
- The differences in mechanical properties are related to plaque composition.
- IVUSE is a sensitive technique for detecting pharmacologically-induced mechanical changes in rabbit atherosclerotic plaques.

ObjectivesThe present study aimed to investigate the effect of potent rosuvastatin therapy on plaque mechanical stabilization as seen on IVUSE.Methods14 purebred New Zealand rabbits were fed a high-cholesterol diet; the abdominal aorta endothelium was balloon-injured after 2 weeks; at week 13, 7 rabbits received rosuvastatin (1.5 mg/kg/day), and the other 7 received an equal volume of saline. IVUS images of abdominal aortas were acquired, and 2 consecutive frames near the end-diastole images in situ were used to construct an IVUS elastogram.ResultsControl rabbits showed a significant increase in shear strain (SS) and area strain (AS) in total plaques. The rosuvastatin group showed no change in SS and AS, but serum TG and LDL-C levels were reduced, with less lipid deposition, macrophage infiltration, production of proinflammatory cytokines and apoptosis in plaques. The changes in SS and AS from baseline between groups significantly differed (SS: 1.15 (1.96) % vs. −0.99 ± 2.83%, p = 0.013; AS: 1.25 (2.29) % vs. −1.67 ± 5.05%, p = 0.022). At follow-up, for controls, strain values were increased in the shoulder of eccentric plaques (SS: 2.66 ± 1.31% vs. 4.86 ± 1.93%, p = 0.016; AS: 4.45 ± 2.33% vs. 7.91 ± 2.74%, p = 0.009) but not the plaque body. Changes in SS and AS in the plaque shoulder differed between the control and rosuvastatin groups (SS: 2.20 ± 2.17% vs. −0.87 ± 3.31%, p = 0.028; AS: 2.10 (4.61) % vs. −2.75 ± 5.97%, p = 0.009).ConclusionRosuvastatin therapy in rabbits with atherosclerotic plaques led to less vulnerable plaque features. IVUSE is a very sensitive technique for detecting pharmacologically-induced mechanical changes in rabbit atherosclerotic plaques.