Author + information
- Bu-Chun Zhang1
Despite the well-described association between plaque morphology and acute coronary syndromes, there is limited in vivo evidence regarding the temporal evolution of non-culprit coronary plaque morphology under standard medical treatment. We aimed to evaluate the changes in plaque morphology of non-culprit lesions over time by optical coherence tomography (OCT) using a qualitative and a quantitative approach, and further identify factors that are associated with these changes.
119 patients had undergone serial OCT examination of the same vessel in our institution between 1/1/2009 and 31/8/2014. Among those, 72 patients with 257 non-culprit segments fitted the inclusion criteria and were analyzed. Non-culprit coronary segments were matched between baseline and follow-up pullbacks. OCT plaque characterization including automated attenuation analysis was performed for both intervals and changes over a median follow-up of 6.2 months were evaluated.
On a segment-level basis, lumen area decreased from baseline to follow-up, whereas fibrous cap thickness increased. Similarly, plaque attenuation indexes at follow-up were significantly decreased compared to baseline. In most segments (68.5%), plaque morphology did not change. Favorable change was observed in 18.4% of segments and unfavorable in 12.9%. There were no robust clinical predictors of favorable or unfavorable change in plaque morphology. Attenuation analysis supported the qualitative characterization, showing significantly different attenuation between different plaque types.
In non-culprit coronary segments of patients with coronary artery disease under standard medical therapy, fibrous cap thickness increases over time. However, in individual segments, there are observations of both plaque stabilization and destabilization, even within the same artery and patient. No clinical factor could reliably predict these changes, implying a need for new hypotheses and study designs.