Non-Fibroatheroma Lesion Phenotype and Long-Term Clinical Outcomes : A Substudy Analysis From the PROSPECT Study

Objectives The purpose of this study was to determine the clinical impact of non-fibroatheroma lesion phenotype in patients presenting with an acute coronary syndrome (ACS). Background Although fibroatheromas (FAs) are known to be clinically unstable, the impact of non-FA lesion phenotype on clinical outcomes has not been studied. Methods In the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study, patients presenting with an ACS underwent 3-vessel grayscale and virtual histology intravascular ultrasound (VH-IVUS) after successful percutaneous intervention for all culprit lesions and were followed for 3 years. Patients were divided into those who had only the non-FA phenotype (pathological intimal thickening or fibrotic and/or fibrocalcific lesions) versus those who had at least 1 nonculprit FA. Results Among 2,880 nonculprit lesions identified by VH-IVUS, 39.8% were non-FAs (1,042 pathological intimal thickening, 72 fibrotic, and 33 fibrocalcific). Nonculprit major adverse cardiac events (MACE) (death, myocardial infarction, or urgent rehospitalization for progressive or unstable angina) were attributed to only 7 non-FA lesions (0.7%) versus 43 FA lesions (2.7%, p Conclusions Non-FA lesions were clinically stable and were rarely associated with clinical events during 3 years of follow-up. The intermediate-term prognosis in patients presenting with ACS in whom all nonculprit lesions are non-FAs is favorable. (PROSPECT: An Imaging Study in Patients With Unstable Atherosclerotic Lesions; NCT00180466 )