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

The long-term prognostic impact of presumed high-risk morphologic plaque features detected by intracoronary optical coherence tomographic (OCT) imaging remains largely unknown.

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.

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).

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.

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. (Relationship Between OCT Coronary Plaque Morphology and Clinical Outcome [CLIMA]; NCT02883088).