Clinical Implications of Poststent Optical Coherence Tomographic Findings: Severe Malapposition and Cardiac Events

Abstract

Objectives: This study sought to evaluate the impact of poststent optical coherence tomography (OCT) findings, including severe malapposition, on long-term clinical outcomes.

Background: Suboptimal OCT findings following percutaneous coronary intervention (PCI) are highly prevalent; however, their clinical implications remain controversial.

Methods: Of the patients registered in the Yonsei OCT registry, a total of 1,290 patients with 1,348 lesions, who underwent OCT immediately poststenting, were consecutively enrolled for this study. All patients underwent implantation of drug-eluting stents. Poststent OCT findings were assessed to identify predictors of device-oriented clinical endpoints (DoCE), including cardiac death, target vessel-related myocardial infarction (MI) or stent thrombosis, and target lesion revascularization (TLR). Significant malapposition criteria associated with major safety events (MSE) were also investigated, such as cardiac death, target vessel-related MI, or stent thrombosis.

Results: The median follow-up period was 43.0 months (interquartile range [IQR] 21.4 to 56.0 months). The incidence rates of stent edge dissection, tissue prolapse, thrombus, and malapposition after intervention were not associated with occurrence of DoCE. However, patients with significant malapposition (total malapposition volume [TMV] ≥7.0 mm³] exhibited more frequent MSE. A smaller minimal stent area (MSA) was identified as an independent predictor for DoCE (hazard ratio [HR]: 1.20 [95% confidence interval [CI]: 1.00 to 1.43]; p = 0.045). Malapposition with TMV ≥7.0 mm³ was found to be an independent predictor of MSE (HR: 6.12 [95% CI: 1.88 to 19.95]; p = 0.003). Follow-up OCT at 3, 6, or 9 months after PCI showed that poststent TMV ≥7.0 mm³ was related to a greater occurrence of late malapposition and uncovered struts.

Conclusions: Although most suboptimal OCT findings were not associated with clinical outcomes, a smaller MSA was associated with DoCE, driven mainly by TLR, and significant malapposition with TMV ≥7.0 mm³ was associated with more MSE after PCI. (Yonsei OCT [Optical Coherence Tomography] Registry for Evaluation of Efficacy and Safety of Coronary Stenting; Yonsei OCT registry; NCT02099162).

Keywords: drug-eluting stent(s); malapposition; optical coherence tomography; percutaneous coronary intervention; total malapposition volume.