Long-Term Prognostic Impact of OCT-Derived High-Risk Plaque Features: Extended Follow-Up of the CLIMA Study

Background: The long-term prognostic impact of presumed high-risk morphologic plaque features detected by intracoronary optical coherence tomographic (OCT) imaging remains largely unknown. Objectives: The aim of this study was to assess the relationship between OCT plaque characteristics and cardiovascular outcomes throughout 5 years as part of the CLIMA (Relationship Between OCT Coronary Plaque Morphology and Clinical Outcome) study. Methods: In the multicenter, international, prospective CLIMA study, 1,003 patients underwent OCT evaluation of the untreated proximal left anterior descending coronary artery. The 4 prespecified high-risk criteria were thin-cap fibroatheroma (TCFA), minimum luminal area <3.5 mm², lipid arc >180°, and the presence of macrophages. The primary composite endpoint was cardiac death or target segment myocardial infarction (TS-MI). Results: At 5-year follow-up (median 1,825 days; Q1-Q3: 1,137-1,825 days), the presence of all 4 OCT criteria, observed in 3.6% of patients at baseline, was independently associated with the primary endpoint (adjusted HR: 4.33; 95% CI: 2.01-9.33). The individual risks for cardiac death (HR: 3.73; 95% CI: 1.59-8.73) and TS-MI (HR: 7.02; 95% CI: 2.37-20.77) were significantly increased in patients with vs without all 4 OCT criteria. The combined presence of 4 OCT criteria remained significantly associated with the primary endpoint independently of high-intensity lipid-lowering therapy (adjusted HR: 2.94; 95% CI: 1.21-7.11). The presence of any TCFA was observed in 18.3% of patients and was similarly predictive of cardiac death and/or TS-MI. Conclusions: The simultaneous presence of 4 OCT high-risk features, although infrequent, was independently associated with cardiac death or TS-MI on long-term follow-up. The presence of any TCFA was 5-fold as prevalent and similarly predictive of 5-year adverse outcomes.