Abstract 4515: Treatment With Statin on Atheroma Regression Evaluated by Intravascular Ultrasound With Virtual Histology (TRUTH Study)
Background: Intensive lipid-lowering therapy with statins has been demonstrated to produce regression of coronary artery plaques. However, the actual changes in the coronary arterial plaque composition associated with statin therapy have not yet been well delineated.
Methods: A prospective, open-label, randomized multicenter study was performed at 11 centers in Japan. One hundred and sixty-four patients with stable or unstable angina were randomly assigned to either pitavastatin treatment (4 mg/day, intensive lipid-lowering) or pravastatin treatment group (20 mg/day, moderate lipid-lowering). Non-percutaneous coronary intervention (PCI) lesions (>5mm distal and/or proximal to the stent) were evaluated by Virtual Histology (VH) intravascular ultrasound (IVUS) at the time of PCI and after 24 – 40 weeks of statin therapy.
Results: The mean low-density lipoprotein cholesterol levels decreased significantly from 126±28 to 74±22 mg/dL (−41%, p<0.0001) in the pitavastatin group and from 137±35 to 95±23 mg/dL (−29%, p<0.0001) in the pravastatin group. Gray-scale IVUS analysis demonstrated significant decrease of the plaque volume from 9.06±2.90 to 8.86±2.78 mm3/mm (−1.9%, p<0.05) in the pitavastatin group, but no significant change in the pravastatin group (from 8.83±3.67 to 8.71±3.60 mm3/mm, −0.6%). VH-IVUS analysis revealed that the statins produced a significant decrease of the fibro-fatty component (pitavastatin: from 1.09±0.88 to 0.81±0.60 mm3/mm, p<0.01; pravastatin: from 1.05±1.03 to 0.83±0.85 mm3/mm, p<0.001) and increase the dense-calcium component (pitavastatin: from 0.42±0.35 to 0.55±0.43 mm3/mm, p<0.0001; pravastatin: from 0.44±0.47 to 0.55±0.56 mm3/mm, p<0.01) of the plaques. There was a negative correlation between the changes in the fibro-fatty and dense-calcium components in both groups (pitavastatin: r=−0.75; pravastatin: r=−0.69).
Conclusions: Intensive lipid-lowering therapy with pitavastatin produced significant regression of coronary arterial plaques. The increase of the dense-calcium component and decrease of the fibro-fatty component tended to be more pronounced in the pitavastatin group. These changes of coronary arterial plaque composition may be one of the stabilizing effects of statin therapy.