Coronary atheroma volume and cardiovascular events during maximally intensive statin therapy

Abstract

The impact of baseline coronary plaque burden on the clinical outcome in patients receiving aggressive low-density lipoprotein cholesterol (LDL-C) lowering therapy to levels <70 mg/dL is unknown. We assessed the prognostic significance of baseline coronary plaque burden following high-intensity statin therapy. SATURN used serial intravascular ultrasound (IVUS) to measure coronary atheroma volume in 1039 patients before and after 24 months of treatment with rosuvastatin 40 mg or atorvastatin 80 mg. This post hoc analysis compared the relationship between baseline percent atheroma volume (PAV) and major adverse cardiovascular events (MACE: death, myocardial infarction, stroke, coronary revascularization, hospitalization for unstable angina) in patients with baseline PAV less than (n = 519) or greater than (n = 520) the median. Patients with a higher baseline PAV had a similar LDL-C compared with those with a lower baseline PAV at baseline (119.0 ± 29 vs. 121.0 ± 27 mg/dL, P = 0.09) and at follow-up (65.3 ± 23 vs. 65.8 ± 22 mg/dL, P = 0.47). In multivariable analysis, each standard deviation increase in baseline PAV was associated with a 28% increase in MACE [HR 1.28 (1.05, 1.57), P = 0.01]. Those with the highest quartile of baseline PAV (>41.8%) had a 2-year cumulative MACE rate of 12%, which was significantly higher (log-rank P = 0.001) than MACE rates of all lower PAV quartiles (MACE: quartile 3, 2, and 1 were 5.7, 7.9, and 5.1%, respectively). LDL-C levels at baseline [HR 0.96 (0.79, 1.18), P = 0.73] and on-treatment [HR 1.19 (0.83, 1.73), P = 0.35] were not associated with MACE. Following 2 years of high-intensity statin therapy, a baseline coronary atheroma volume predicted MACE, despite the achievement of very low on-treatment LDL-C levels.