Background: In second- and third-generation drug-eluting stent (DES) era, in-stent restenosis (ISR) is not commonly seen. However, a few patients still need repeat revascularizations for recurrent ISR even after second- and third-generation DES implantation.
Methods: From January 2012 to March 2017, 2339 lesions underwent second- and third-generation DES (Nobori, Promus Element, Resolute Integrity, Xience, Ultimaster and Synergy) implantation, of which 95 lesions (4.1%) underwent revascularization for first ISR. All lesions were divided into two groups of recurrent ISR group and non-recurrent ISR group. After successful optical coherence tomography (OCT) guided revascularization for all lesions, we investigated characteristics of recurrent ISR, and 2 years follow-up were completed.
Results: The mean age was 70.8 ± 11.7 years, and 73.2% were males. Among 56 DES-ISR lesions which were assessed by OCT, recurrent ISR was seen in 33.9% (N = 19) at 2 years follow-up after revascularization for first ISR. Serum low-density lipoprotein-cholesterol (LDL-C) level was higher in recurrent ISR group compared with non-recurrent ISR group (114.1 ± 53.9 mg/dl vs. 90.9 ± 27.8 mg/dl, P = 0.04) and heterogeneous tissue pattern was more frequently found in recurrent ISR group compared with non-recurrent ISR group (63.2% vs. 27.0%, P = 0.03). Multivariate analysis identified a heterogeneous tissue pattern (odds ratio 3.71; 95% confidence interval 1.09-12.59; P = 0.03) as an independent predictor of recurrent restenosis.
Conclusion: Recurrent ISR of second- and third-generation DES was associated with heterogeneous tissue pattern of first ISR, and high LDL-C level was associated with recurrence.