Specific calcium deposition on pre-procedural CCTA at the time of percutaneous coronary intervention predicts in-stent restenosis in symptomatic patients.

Purpose: To characterize preprocedural coronary atherosclerotic lesions derived from CCTA and assess their association with in-stent restenosis (ISR) after percutaneous coronary intervention (PCI).

Materials and methods: This retrospective cohort-study included patients who underwent CCTA for suspected coronary artery disease, subsequent index angiography including PCI and surveillance angiography within 6-8 months after the index procedure. We performed a plaque analysis of culprit lesions on CCTA using a dedicated plaque analysis software including assessment of the surrounding pericoronary fat attenuation index (FAI) and compared findings between lesions with and without ISR at surveillance angiography after stenting.

Results: Overall 278 coronary lesions in 209 patients were included. Of these lesions, 43 (15.5 ​%) had ISR at surveillance angiography after stenting while 235 (84.5 ​%) did not. Likewise, plaque composition such as volume of calcification [129.8 mm³ (83.3-212.6) vs. 94.4 mm³ (60.4-160.5) p ​= ​0.06] and lipid-rich and fibrous plaque volume [38.4 mm³ (19.4-71.2) vs. 38.0 mm³ (14.0-59.1), p ​= ​0.11 and 50.4 mm³ (26.1-77.6) vs. 42.1 mm³ (31.1-60.3), p ​= ​0.16] between lesion with and without ISR were not statistically significant. However lesions associated with ISR were more eccentric (n ​= ​37, 86.0 ​% versus n ​= ​159, 67,7 ​%; p ​= ​0.03) and more frequently demonstrated calcified portions on opposite sides on the vessel wall on cross-sectional datasets (n ​= ​24, 55.8 ​% versus n ​= ​55, 23.4 ​%, p ​= ​0.001). FAI_lesion was significantly different in lesions with ISR as compared to those without ISR [-76.5 (-80.1 to -73.6) vs. -80.9 (-88.9 to -74.0), p ​= ​0.02]. There was no difference with respect to FAI_RCA between the two groups [-77.4 (-81.9 to -75.6) vs. -78.5 (-86.0 to -71.0), p ​= ​0.41].

Conclusion: Coronary lesions associated with ISR at surveillance angiography demonstrated differences in the arrangement of calcified portions as well as an increased lesion-specific pericoronary fat attenuation index at baseline CCTA. This latter finding suggests that perivascular inflammation at baseline may play a major role in the development of in-stent restenosis.