Heart rate lowering treatment leads to a reduction in vulnerable plaque features in atherosclerotic rabbits

摘要: OBJECTIVE To investigate the effect of a heart rate (HR) lowering agent (Ivabradine) on features atherosclerotic plaque vulnerability with magnetic resonance imaging (MRI), ultrasound imaging, and histology. APPROACH AND RESULTS Atherosclerosis was induced in abdominal aorta 19 rabbits. Nine rabbits were treated Ivabradine (17 mg/kg/day) during entire study period. At week 14, performed. Plaque size quantified contrast-enhanced T1-weighted MR images. Microvascular flow, density, permeability studied dynamic MRI. biomechanics by measuring aortic distension ultrasound. After, animals sacrificed histology HR reduced 16% (p = 0.026) Ivabradine-treated animals. No differences absolute relative vessel wall beat-to-beat found, but due to reduction HR, frequency biomechanical load reduced. (MR histology) similar between groups. Although microvessel density (histology) groups, AUC Ktrans, indicative for microvasculature permeability, decreased 24% 0.029) 32% 0.037), respectively. Macrophage content (relative RAM11 positive area) 44% (p<0.001) CONCLUSIONS treatment an rabbit model is associated vulnerable features. The current suggests that may be beneficial inducing or maintaining more stable phenotype.