Intracoronary imaging guided percutaneous coronary intervention of stent restenosis: does it make a difference?
Authors: Barradas M , Pires-Morais G , Melica B , Goncalves M , Espada Guerreiro C , Santos L , Rodrigues A , Braga P , Fontes-Carvalho R 
Published: November 2023

Abstract

Background
In-stent restenosis (ISR) remains the most common cause of stent failure after percutaneous coronary intervention (PCI). Compared to coronary angiography (CA), intracoronary imaging (ICI) provides a more accurate and detailed characterization of the degree of ISR and may help identify the underlying pathophysiological mechanism. Although recommended in the European guidelines, the impact of ICI in clinical outcomes in ISR is still under discussion.

Purpose
Our study aimed to analyze and compare clinical outcomes between CA PCI (group 1 - G1) and ICI-guided PCI (Intravascular ultrasound (IVUS) or optical coherence tomography (OCT)) (group 2 - G2).

Methods
We performed a retrospective single-center review of all consecutive patients with ISR treated in our center from September 2014 to January 2022. Patients with acute stent thrombosis were excluded. Primary endpoint was defined as death by all causes and secondary endpoint as a composite of cardiovascular (CV) mortality, culprit ISR PCI and ischemic stroke.

Results
130 patients were included (mean age 66.23 ± 11.832 years, 77.7% male and mean follow-up period (FUP) 48.70 ± 27.356 months). Mean left ventricular ejection fraction was 50.19 ± 10.509%, 66.2% had dyslipidemia, 45.3% hypertension, 38.5% diabetes, 36.2% heart failure and 29.2% previous multivessel PCI. A total of 142 ISR lesions from 136 arteries were treated and ICI was used in 37 (28.5%) patients (IVUS in 16 (12.3%) and OCT in 21 (16.2%)). The ISR coronary segment and pattern is described in Table 1. The mechanism for ISR was identified in 23 lesions. The most common indication for coronary angiography was stable angina in 34.6% and NSTEMI in 31.5% and ISR was the culprit in 128 (98.5%) of the cases. The groups were well matched regarding baseline characteristics and comorbidities. PCI strategy was more often drug-eluting stenting (DES) vs drug-coated balloon (DCB) in group 2 (DES 18.3% vs 51.4% and DCB 81.7% vs 43.2% in G1 and G2 respectively). And, as expected, treatment of bifurcation lesions was more frequent in group 2 (9.7% G1 vs 30.6% G2). During the FUP there were 10 (7.7%) CV deaths and 19 (14.6%) non-CV deaths (19 in G1 and 0 in G2). The composite outcome of CV mortality, ischemic stroke and culprit ISR PCI occurred in 19 (20.2%) patients in G1 and 1 (2.7%) patient in G2. The use of ICI was associated with reduced all-cause mortality (HR=0.667 [95% CI 0.584-0.760], p=0.011) and reduced composite outcome (B (95%CI): -0.251 (-0.455 - -0.046), p=0.017). No difference between IVUS or OCT was found. The PCI strategy (DES vs DCB), stent type, length or diameter were not predictors of outcomes.

Conclusion
In IRS PCI, the use of ICI compared to standard of care CA was associated with a reduction in all-cause mortality and composite outcome of CV mortality, culprit ISR PCI and ischemic stroke. The strategy of PCI differed with DES being used more frequently than DCB. No difference between IVUS or OCT was found.