Contrast Staining Outside the Sirolimus-Eluting Stent Leading to Coronary Aneurysm Formation

Abstract

A 69-year-old man with prior myocardial infarction (hypertension; dyslipidemia; smoking; no diabetes; and no history of allergy, autoimmune disease, or vasculitis) underwent sirolimus-eluting stent (SES) implantation (3.0 mm in diameter; 33 mm in length) for chest pain on exertion with chronic total occlusion of the left anterior descending coronary artery (LAD) ( Figure 1A through 1C and Video 1). Intravascular ultrasound examination after SES implantation demonstrated well-expanded stent struts without evidence of incomplete stent apposition (ISA) ( Figure 1D through 1F).Follow-up angiography at 8 months after initial SES implantation demonstrated multifocal contrast staining outside the stent contour with no evidence of angiographic restenosis ( Figure 2A and Video 2). Subsequently, at 16 months after stenting, coronary angiography showed that the areas of contrast staining outside the stent contour increased in size ( Figure 2B and Video 3). At 23 months after stenting, coronary artery aneurysm (CAA) formation was demonstrated in the midportion of the SES ( Figure 2C and Video 4). The first 8-month angiography was a protocol-driven follow-up study for the index LAD lesion. The second 16-month angiography was also a protocol-driven follow-up study for the circumflex coronary artery lesion treated 8 months before. Similarly, the third 23-month angiography Figure 1. Baseline angiographic and intravascular ultrasound findings. A, Chronic total occlusion of the proximal LAD before percutaneous coronary intervention (arrow); B, collateral flow into the LAD from the right coronary artery (arrow); C, LAD after SES (3.0 mm in diameter; 33 mm in length) implantation (arrows); D through F, intravascular ultrasound images after SES implantation demonstrating well-expanded stent struts without evidence of incomplete stent apposition.

Incidence, Risk Factors, and Clinical Sequelae of Angiographic Peri-Stent Contrast Staining After Sirolimus-Eluting Stent Implantation

“…More recently, Kon et al reported a case with VLST of SES demonstrating serial changes in PSS leading to aneurysm formation, as well as histopathological evidence of hypersensitivity vasculitis in the stented segment. 22 Therefore, accumulating evidence suggests that VLST associated with ISA and/or PSS might be mechanistically related to chronic inflammatory reactions. Inflammation leading to destruction of the medial wall might lead to loss of elastic vessel integrity and aneurismal dilatation.…”

Optical Coherence Tomography Findings in Lesions After Sirolimus-Eluting Stent Implantation With Peri-Stent Contrast Staining

“…Several mechanisms of ISA including positive arterial remodeling, vessel wall injury at stent implantation, dissolution of jailed thrombus or plaque debris, and hypersensitivity reaction of coronary artery have been proposed, 2,4,5,21 but the mechanism of PSS is still unclear. Kon et al 4 reported a case with PSS in a lesion after SES implantation.…”

“…We named this finding peri-stent contrast staining (PSS), which is an angiographical finding of contrast medium stain outside the stent being >20% of the stent diameter, and it has been preliminary reported that PSS after sirolims-eluting stent (SES) implantation could predict late stent thrombosis of the lesion with PSS. 3 Although it was unclear what PSS consisted of, Kon et al 4 reported that a case with PSS had histopathological evidence of hypersensitivity reaction in the lesion after SES implantation.…”

Angioscopic Assessment of Peri-Stent Contrast Staining Following Drug-Eluting Stent Implantation

“…5,26- 28 Kon et al reported a case of VLST with ISA, and after pathologic evaluation they proposed that chronic inflammation and hypersensitivity vasculitis might be important underlying mechanisms of ISA. 4 As described before, an abnormal vascular response mainly composed of inflammation is thought to be prolonged at the PSS site. Therefore, we infer that PSS is a result of inflammatory reaction to the polymer or drug.…”