Clinical profile and optical coherence tomography based morphological characteristics of coronary in-stent restenosis: A cross-sectional study.

BACKGROUND

In-stent restenosis (ISR), a complication after percutaneous coronary intervention (PCI), involves neointimal hyperplasia and neoatherosclerosis. With the rise of drug-eluting stents (DES), Optical Coherence Tomography (OCT) has become essential for evaluating ISR morphology and guiding treatment decisions.

OBJECTIVES

This study aimed to investigate the morphological patterns and clinical features of ISR in an Indian cohort using OCT, identify common morphological characteristics, and explore their relationship with ISR duration.

METHODS

A cross-sectional observational study at a tertiary care center in New Delhi included 50 patients with angiographically confirmed ISR. OCT was used to assess qualitative and quantitative parameters of restenotic lesions, including neointimal patterns, minimal lumen area (MLA), minimal stent area (MSA), lipid content, and calcium burden. The correlation between ISR duration (early vs. late) and OCT features was also analyzed.

RESULTS

The mean age was 58.08 ± 9.68 years, with 74 % male participants. Most patients (80 %) had late ISR. Hypertension (66 %) and diabetes (44 %) were the most common comorbidities, and chronic stable angina was the most frequent presentation (60 %). OCT findings showed heterogeneous neointima in 64 %, stent under-expansion in 42 %, and calcification in 82 %. Late ISR had a significantly larger neointimal area, though no other features correlated significantly with ISR duration.

CONCLUSIONS

Neoatherosclerosis, especially heterogeneous neointima, is the primary morphological cause of ISR in this cohort. Stent under-expansion is a key contributor. OCT is valuable for diagnosing and planning ISR interventions. Larger studies are needed for broader conclusions and standardized management.