Analysis of the Clinical Covariates Associated with the Risks of Additional Percutaneous Coronary Intervention due to In-stent Restenosis or de Novo Lesions in Patients with Implanted Drug-eluting Stents

Percutaneous coronary intervention (PCI) with drug-eluting stent (DES) and appropriate antiplatelet therapy is a standard therapeutic procedure for patients who develop ischemic heart events. While the incidence of restenosis with DES is much less than that with bare metal stents, additional PCI for in-stent restenosis or de novo lesions is still required for some patients in clinical practice. In the present study, we performed a retrospective medical chart review for assessing clinical risk factors associated with the additional PCI in DES-implanted patients. Among 358 DESimplanted patients, 143 required additional PCI (75 in-stent restenosis in 75 and 82 de novo lesions) from 6 to 12 months after PCI. Logistic regression analysis revealed that female, multiple stenosis (double/triple vessels) and HbA1c at PCI are significant variables for predicting secondary PCI with odds ratios [95% confidence intervals] of 0.46 [0.25 to 0.85] (relative to male), 2.3/3.6 [1.2 to 4.4/1.9 to 6.8] (relative to single vessel disease) and 1.2 [1.0 to 1.4] (per 1% increment), respectively. When analysis was performed for in-stent restenosis and de novo lesion, separately, multiple stenosis was a significant risk factor for both groups. Interestingly, intensive blood glucose management after PCI was not associated with a significant reduction in the likelihood of additional PCI in overall patients as well as a subgroup of diabetic patients with inappropriate glycemic control (HbA1c ≥6.5%). We concluded that the management of HbA1c in high-risk patients of coronary diseases is the sole modifiable risk factor for reducing the incidence of additional PCI after DES stenting.