Objectives: Percutaneous coronary intervention (PCI)-related cardiac enzyme elevation is an independent risk factor for adverse clinical outcomes, but preprocedural predictors of this complication have not been established. This study evaluated the morphological characteristics of culprit lesions by frequency-domain optical coherence tomography (FD-OCT), and examined their predictive value for procedure-related myocardial injury in patients undergoing elective PCI.
Methods: Sixty-eight patients treated by FD-OCT-guided elective PCI were studied. On the basis of the presence or absence of postprocedural plasma cardiac troponin T (cTnT) elevation, patients were divided into elevation (cTnT-E, n=25) and nonelevation (cTnT-nonE, n=43) groups. FD-OCT examinations of culprit lesions were performed before and after stent implantation, and tissue characteristics were evaluated within a 10-mm-long segment of each lesion.
Results: Clinical parameters were similar between the two groups. Stent length was significantly longer in the cTnT-E group than in the cTnT-nonE group. On baseline OCT images, thin-cap fibroatheroma and calcium deposition were more frequently observed within culprit segments of the cTnT-E group compared with the cTnT-nonE group (32.0 vs. 11.6%, P=0.043, and 72.0 vs. 46.5%, P=0.039, respectively). In addition, colocalization of these two findings was a powerful predictor of PCI-related cTnT elevation (odds ratio 8.40, 95% confidence interval 1.65-52.78, P<0.01). Further, the predictive value of this colocalization was enhanced when the analysis included only spotty calcification (odds ratio 21.00, 95% confidence interval 2.65-454.22, P=0.003).
Conclusion: FD-OCT examination showed that colocalization of thin-cap fibroatheroma and spotty calcification was a powerful predictor of PCI-related cTnT elevation. FD-OCT is useful for stratifying risk during PCI to avoid procedure-related complications.