Impact of intima re-intrusion and expansion within 100 minutes on late lumen loss in percutaneous coronary intervention for diffuse in-stent restenosis

The recurrence of in-stent restenosis (ISR) is reported to be in the range of 20–40% but is especially high in diffuse ISR.1 Previous studies have shown that ISR is due solely to neointimal hyperplasia without stent recoil.2 ISR caused by neointimal proliferation frequently occurs within six months. However, the timing and mechanisms of recurrent ISR are unknown. A serendipitous observation revealed that lumen loss occurred during dwell time of radiation therapy of ISR by intravascular ultrasound (IVUS).3 However, mechanisms and roles of the acute lumen loss are unclear. This prospective study was undertaken to quantify lumen loss within minutes and to discuss the mechanism of recurrence in diffuse ISR. We prospectively enrolled 13 patients with 14 lesions, who underwent successful percutaneous coronary intervention (PCI) for treatment of diffuse ISR (lesion length > 10 mm) in this study. All the patients gave informed consent. Quantitative coronary angiography (QCA) and IVUS were performed before, immediately after, and approximately 100 minutes after intervention. Cutting balloon angioplasty or balloon angioplasty was selected according to the discretion of the operator. A satisfactory angiographic result was defined as final residual stenosis < 25%. All the patients had follow up angiography and follow up IVUS was performed in the nine …