Changes in high-sensitivity troponin according to optical characteristics of neointima and treatment modality of in-stent restenosis
Authors: Nano N , Aytekin A , Ndrepepa G , Seguchi M , Bresha J , Alvarez Covarrubias H A , Nicol P , Rheude T , Wiebe J , Schunkert H , Kufner S , Cassese S , Joner M , Kastrati A , Xhepa E 
Published: October 2022

Abstract

Background
Intravascular imaging studies of native vessel percutaneous coronary intervention (PCI) have shown a relationship between presence of lipid-rich plaques or large necrotic cores and occurrence of periprocedural myocardial injury (PMI). However, limited evidence exists on the relationship between neointimal tissue characteristics, and PMI following PCI of in-stent restenosis (ISR) lesions. Beside neointimal tissue characteristics, treatment modality may represent an additional mechanism influencing PMI in the setting of ISR-PCI. Current ESC guidelines recommend either drug-coated balloon (DCB) or drug-eluting stent (DES) as treatment options for ISR.

Purpose
To investigate the impact of increasing neointimal inhomogeneity and neoatherosclerotic changes of the neointima, as well as of ISR treatment modality on the occurrence of PMI.

Methods
Patients with normal or stable/falling increased baseline high-sensitivity troponin T (hs-cTnT) undergoing intravascular optical coherence tomography (OCT) and subsequent DCB or DES treatment of ISR lesions were included. PMI was classified as “minor” or “major” according to the definitions of a recent ESC/EAPCI consensus document. Quadrant-based neointimal characterization was performed at the frame displaying the maximal % area stenosis and the 5 preceding and following analyzed frames. Neointimal tissue was categorized as homogeneous or inhomogeneous, the latter including heterogeneous, layered or neoatherosclerosis quadrants. Hs-cTnT was measured at the time of admission, 3–6 h after PCI, at 6 h intervals in case of rising values, and on a daily basis thereafter.

Results
Overall, 128 patients were subdivided into low (n=64) and high (n=64) neointimal inhomogeneity groups, based on the median of distribution of non-homogeneous quadrants. No significant between-group differences were detected in terms of hs-cTnT changes (28.0 [12.0–65.8] vs. 25.5 [9.8–65.0] ng/L; p=0.355), or major PMI occurrence (31.2% vs. 31.2%; p=1.000). Similarly, no differences were observed between DCB and DES treated groups in terms of hs-cTnT changes (27.0 [10.0–64.0] vs. 28.0 [11.0–73.0] ng/L; p=0.795), or occurrence of major PMI (28.9% vs. 35.6%; p=0.566). Of note, no significant interaction was observed between optical neointimal characteristics and treatment modality in terms of changes in hs-cTnT (p int = 0.432). There were no significant differences in PMI occurrence between low and high neoatherosclerosis subgroups.

Conclusion
The present study, which combined a detailed, quadrant-based multi-frame neointimal characterization coupled to systematic pre- and post-procedural hs-cTnT measurements in patients undergoing PCI for ISR, showed no association between increasing neointimal inhomogeneity, or increasing expression of neoatherosclerosis, and occurrence of PMI. PMI occurrence was not influenced by the ISR treatment modality (DCB vs. DES), a finding that supports the safety of DCB treatment for ISR.

Funding Acknowledgement
Type of funding sources: None.