Aims: Statins are highly effective in reducing major adverse clinical events, but the direct effects on coronary plaque composition remain debatable. Our aim was to mechanistically evaluate the treatment effect of high-intensity statin therapy on compositional coronary plaque changes.
Methods and results: The third Integrated Biomarker and Imaging Study (IBIS-3) was a prospective, investigator-initiated, single-centre study. Serial radiofrequency intravascular ultrasound (RF-IVUS) measurements of a predefined non-stenotic segment in a non-culprit coronary artery were performed to evaluate the effect of rosuvastatin (intended dose: 40 mg daily) on necrotic core (NC) volume in patients with stable angina or acute coronary syndrome. Changes in lipid core burden index (LCBI) were evaluated through serial near-infrared spectroscopy (NIRS) imaging in a subset. Serial RF-IVUS (and NIRS) data of a median segment of 41 mm (interquartile range: 32 to 49 mm) were complete in 164 (103) patients. Follow-up measurements were performed at six and 12 months in 30 (26) and 134 (77) patients, respectively. Mean levels of low-density lipoprotein cholesterol decreased by 30%, from 2.49 mmol/l to 1.73 mmol/l at the end of follow-up. High-dose rosuvastatin therapy resulted in a non-significant change of -1.4 mm3 (95% CI: -3.0, 0.1) in NC volume during follow-up (p=0.074). The change in NC percentage of total plaque volume was -1.4% (95% CI: -2.4 to -0.4; p=0.006). A neutral effect was also observed on LCBI. Indications of significant regression of NC volume and LCBI in the highest baseline quartiles were observed, which should cautiously be regarded as hypothesis-generating.
Conclusions: High-intensity rosuvastatin therapy during one year resulted in a neutral effect on NC and LCBI within non-stenotic, non-culprit coronary segments with a relatively low atheroma burden. This study has been registered in The Netherlands Trial Register (NTR) nr. 2872.