Additive Effect of Multiple High-Risk Coronary Artery Segments on Patient Outcomes: LRP Study Sub-Analysis.

BACKGROUND: The Lipid Rich Plaque (LRP) Study established the association between high volume of lipidic content (maximum Lipid Core Burden Index [maxLCBI4mm] >400) in the coronary arteries and subsequent non-culprit major adverse cardiac events (NC-MACE). This analysis sought to assess the clinical impact of more than one lipid-rich plaque in the coronary tree. METHODS: The LRP patient population was divided into four cohorts: 1) patients with all segments with maxLCBI4mm = 0; 2) patients with all coronary segments maxLCBI4mm < 400, but >0; 3) patients with 1 segment maxLCBI4mm > 400; and 4) patients with 2+ coronary segments with maxLCBI4mm > 400. Baseline characteristics, plaque-level characteristics, and follow-up outcomes were described. RESULTS: Among 1550 patients, only 3.2 % had all segments with maxLCBI4mm = 0; 65.1 % had segments with maxLCBI4mm > 0 but <400; 22.5 % had one segment with maxLCBI4mm > 400; and 9.5 % had 2+ coronary segments with maxLCBI4mm > 400. Distribution within the coronary tree (one versus multiple arteries) did not differ. Overall, 1269 patients were allocated to follow-up (per study design). The composite of all-cause death, cardiac death, any revascularization, and NC-MACE was statistically higher in patients with 1 segment maxLCBI4mm > 400 and numerically even higher in patients with 2+ segments with maxLCBI4mm > 400. Patients with maxLCBI4mm = 0 had no events within two years. CONCLUSION: There is a stepwise increased risk of all-cause death, cardiac death, any revascularization, and NC-MACE according to the number of coronary segments with maxLCBI4mm > 400. In contrast, maxLCBI4mm = 0 results in a low event rate. CLINICAL TRIAL REGISTRATION: The Lipid-Rich Plaque Study (LRP), https://clinicaltrials.gov/ct2/show/NCT02033694, NCT02033694.