Long-term prognostic impact of optical coherence tomography detected plaque rupture in nonculprit coronary segments.

Background And Aims
Atherosclerotic plaque rupture is largely acknowledged as the main mechanism of acute coronary syndrome. However, the prognostic significance of plaque rupture detected in nonculprit coronary sites remains largely unknown.Methods
We investigated the long-term clinical outcomes of nonculprit plaque rupture detected by optical coherence tomography in the prospective CLIMA study. The primary composite endpoint was cardiac death or target-segment myocardial infarction (TS-MI) through 5-year follow-up.Results
Among 1003 patients (age 64.8y; 24.6% women), nonculprit plaque rupture was observed in 7.3% of patients. Three-vessel disease, total plaque length, thin-cap fibroatheroma and large lipid arc were independently associated with nonculprit plaque rupture. The presence of nonculprit plaque rupture was associated with the primary endpoint at univariable (HR 2.09, 95%CI 1.07-4.08, p = 0.030) but not clinical (adjusted HR 1.70, 95%CI 0.83-3.48, p = 0.145) and morphological (adjusted HR 1.63, 95%CI 0.83-3.21, p = 0.156) multivariable analysis. The individual rates of cardiac death (HR 1.64, 95%CI 0.70-3.85, p = 0.252) and TS-MI (HR 2.87, 95%CI 0.97-8.47, p = 0.057) did not significantly differ between patients with vs without nonculprit plaque rupture. At the Kaplan-meier analysis, the presence of nonculprit plaque rupture was significantly associated with the primary endpoint only in presence of a thin-cap fibroatheroma (TCFA). The presence of nonculprit plaque rupture did not improve the predictive accuracy of any TCFA in multiple prediction models.Conclusions
Nonculprit plaque rupture was associated with cardiac events at univariable but not multivariable analysis. Identification of nonculprit PR did not improve the predictive value of established high-risk morphological features such as TCFA; however, future ad hoc studies are needed to further clarify its potential independent clinical relevance.Clinical Trial Registration
URL: https://www.Clinicaltrials
gov; Unique identifier: NCT02883088.