Stent Underexpansion Is an Underestimated Cause of Intrastent Restenosis: Insights From RESTO Registry
Géraud Souteyrand, Thomas Mouyen, Benjamin Honton, Aurélien Mulliez, Benoît Lattuca, Jean‐Guillaume Dilinger, Sébastien Levesque, Grégoire Rangé, Nicolas Combaret, Stéphanie Marlière, Ouarda Lamallem, Marine Quillot, Édouard Gerbaud, Pascal Motreff, Nicolas Amabile
Abstract
Background Despite improvement in devices, in‐stent restenosis remains a frequent and challenging complication of percutaneous coronary interventions. Methods and Results The RESTO (Morphological Parameters of In‐Stent Restenosis Assessed and Identified by OCT [Optical Coherence Tomography]; study NCT04268875) was a prospective multicenter registry including patients presenting with coronary syndromes related to in‐stent restenosis. All patients underwent preintervention OCT analysis, which led to analysis of in‐stent restenosis phenotype, number of strut layers, and presence of stent underexpansion. The primary end point was the in‐stent restenosis type according to the OCT morphological classification. The 1‐year incidence of target vessel failure (a composite of death from cardiac causes, target‐vessel myocardial infarction, or ischemia‐driven target‐vessel revascularization) was assessed. The study included 297 patients. The culprit stent was a drug‐eluting stent in 74.2% of cases. OCT analysis revealed the presence of neoatherosclerosis in 57% (52% calcified), neointimal hyperplasia in 43% (58% homogeneous), stent underexpansion (minimal stent area <4.5 mm 2 ) in 43%, and multiple stent layers in 30%. The prepercutaneous coronary intervention OCT analysis modified the operator's strategy for management in 30% of cases. Treatment involved drug‐eluting stent implantation in 61.6% and drug‐eluting balloon angioplasty in 36.1% of cases with only 63.2% optimal results. The 1‐year target vessel failure incidence was 11% (95% CI, 9%–13%). Residual postpercutaneous coronary intervention stent underexpansion was associated with significantly higher target vessel failure incidence (19% [95% CI, 14%–24%] versus 7% [95% CI, 5–9], P =0.01). Conclusions OCT identified neoatherosclerosis and neointimal hyperplasia in comparable proportions. Stent underexpansion was frequent and favored subsequent adverse clinical outcomes.