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Updated: Jan 30, 2026

Imaging In-Stent Restenosis: An Inexpensive, Reliable, and Rapid Preclinical Model
Published on: September 14, 2009
Coronary restenosis of in-stent protruding bump with rapid progression: Optical frequency domain imaging and
Kenji Kawai1, Hirokuni Akahori1, Takahiro Imanaka1
1Division of Cardiovascular Medicine and Coronary Heart Disease, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan.
Insights
Recurrent in-stent restenosis (ISR) after drug-eluting stent (DES) implantation is rare but possible. Multimodality imaging aids in diagnosing complex ISR morphologies, guiding treatment for challenging coronary artery disease cases.
Area of Science:
- Cardiovascular Medicine
- Interventional Cardiology
- Medical Imaging
Background:
- In-stent restenosis (ISR) remains a significant challenge following percutaneous coronary intervention (PCI), even with advanced drug-eluting stent (DES) technology.
- This case highlights a rare instance of recurrent ISR in a patient with non-ST elevation acute coronary syndrome (NSTE-ACS) undergoing hemodialysis.
Observation:
- The patient presented with recurrent NSTE-ACS, and coronary angiography revealed ISR in the left circumflex artery (LCx) previously treated with DES.
- Intravascular imaging, including optical frequency domain imaging and angioscopy, identified an eccentric protruding mass with an irregular, high-backscatter surface, described as an in-stent bump.
Findings:
- Despite successful treatment of the ISR lesion with a drug-coated balloon, the patient experienced further NSTE-ACS due to new de novo lesions and re-restenosis.
- Multimodality assessment proved crucial in diagnosing the complex morphology of the recurrent restenosis, including a calcified nodule.
Implications:
- The presence of an in-stent protruding bump on intravascular imaging may indicate a higher risk of recurrent ISR.
- Multimodality imaging assessment is valuable for differentiating ISR tissue and guiding management strategies in complex coronary artery disease.
- This case underscores the importance of comprehensive assessment and tailored treatment approaches for patients experiencing ISR after DES implantation.
Abstract:
In-stent restenosis (ISR) remains a tough problem after percutaneous coronary intervention (PCI) despite advances in technology of drug-eluting stents (DES). A 63-year-old man undergoing hemodialysis was diagnosed with non-ST elevation acute coronary syndrome (NSTE-ACS). An emergency coronary angiography (CAG) revealed severe stenosis in the middle left circumflex artery (LCx). After pre-dilatation with non-compliant balloon, primary PCI was successfully performed with DES implantation. Four months after, CAG was performed again and verified ISR of LCx under diagnosis of recurrent NSTE-ACS. Subsequently multimodality intravascular imaging assessment was performed for the ISR lesion. Optical frequency domain imaging showed the eccentric protruding mass with irregular surface with high-backscatter, whereas angioscopy revealed the in-stent bump with yellow color. The ISR lesion was successfully treated by drug-coated balloon angioplasty. However, he suffered recurrent NSTE-ACS five months later. CAG revealed de novo stenotic lesions not only in re-restenosis of LCx but also in proximal left anterior descending artery and ostium of right coronary artery. He was scheduled to undergo coronary artery bypass grafting for three-vessel disease. Multimodality assessment is useful to diagnose the recurrent restenosis lesion with calcified nodule. <Learning objective: In-stent restenosis (ISR) is rarely recurrent even after drug-eluting stent (DES) implantation. In-stent protruding bump is observed in types of ISR morphology by intravascular imaging, and the finding suggests the possibility of recurrent ISR. Diagnosis of the morphology is sometimes difficult, but multimodality imaging assessment is useful to distinguish the ISR tissue.>.
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