Qualitative and quantitative neointimal characterization by optical coherence tomography in patients presenting with in-stent restenosis.

AIMS

To describe optical coherence tomography (OCT) findings in patients with in-stent restenosis (ISR) and determine predictors of neointimal patterns and neoatherosclerosis.

METHODS AND RESULTS

Patients undergoing OCT prior to PCI for ISR in three European centres were included. Analyses were performed in a core laboratory. Qualitative and quantitative [gray-scale signal intensity (GSI)] neointima analyses were performed on a per quadrant basis. A total of 107 patients were included. Predominantly homogeneous lesions included 4.5% (0.0-14.3) non-homogeneous quadrants, while predominantly non-homogeneous ones included 28.1% (20.3-37.5) homogeneous quadrants. Mean GSI values differed significantly between homogeneous [108.4 (92.5-123.6)], non-homogeneous [79.9 (61.2-95.9)], and neoatherosclerosis [88.3 (72.8-104.9)] quadrants (p < 0.001 for all comparisons). Stent underexpansion was observed in 48.5% and 61.1% of lesions, respectively (p = 0.225). Female sex and maximal neointimal thickness independently correlate with a non-homogeneous pattern, while angiographic pattern and diabetes mellitus inversely correlate with such pattern. Time from index stenting procedure was the only independent predictor of neoatherosclerosis.

CONCLUSIONS

Different neointimal patterns coexist in a significant proportion of ISR lesions. GSI values differ significantly between neointimal categories. Neoatherosclerosis is a time-dependent phenomenon, displaying different time courses in DES compared to BMS, with earlier appearance in the former group. Stent underexpansion is a frequent finding in patients with ISR.