Restenosis after drug-coated balloon therapy for in-stent restenosis: an overview of case findings

Abstract Background The optimal treatment protocol for patients with drug-eluting coronary artery stent (DES) restenosis who develop restenosis after treatment with drug-coated balloon (DCB) is unclear. Purpose To investigate independent factors of restenosis after DCB angioplasty for in-stent restenosis (ISR) of DES. Methods We examined 69 patients who underwent percutaneous coronary intervention (PCI) with DCB for ISR of DES from 5 April 2019 to 19 April 2024 at our hospital. A total of 82 lesions were evaluated, including lesions treated multiple times or differently in the same patient. The lesions were divided into two groups based on repeat restenosis verified by coronary angiography or other clinical status (RRVA) after PCI by DCB for DES ISR (PDDI) (RR group, n=26 lesions). The remaining 56 lesions showed no RRVA after PDDI (NR group). The clinical characteristics and laboratory data (mean ± standard error) were compared between the two groups using the t-test and Chi-squared test. In addition, we examined laboratory data at the time of PDDI and RRVA confirmation using multiple logistic regression analyses (MLRA). Moreover, we estimated clinical and intravascular ultrasound (IVUS) characteristics before PDDI using MLRA. Results Age (72.4±1.04 vs. 72.2±1.4 years) and BMI (23.9±0.77 vs. 24.6±0.45 kg/m2) were comparable between the two groups, whereas the proportion of men was higher in the RR group (96%) than in the NR group (78.6%, P=0.0484). Low-density lipoprotein (LDL) level at RRVA confirmation was higher in the RR group (110±9.73) than in the NR group (86.6±4.52, P=0.0182). Hypertension (odds ratio: 0.2541; 95%CI: 0.078–0.8279; P=0.0230) and acute myocardial infarction (odds ratio: 0.0779; 95%CI: 0.0085–0.7129; P=0.0238) at PDDI confirmation were negative predictors for RRVA by MLRA. Further, LDL level at RRVA confirmation was a positive predictor (odds ratio: 1.0207; 95%CI: 1.004–1.0372; P=0.0124). Additionally, high-density lipoprotein (HDL) was a negative risk factor (odds ratio: 0.9299; 95%CI: 0.8778–0.9850; P=0.0134) for RRVA. Moreover, in IVUS before PDDI, calcification of 270° in the lesion (odds ratio: 7.0344; 95%CI: 1.1110–44.3579; P=0.0383) and overlapping of two stents (odds ratio: 29.0249; 95%CI: 3.2999–288.2963; P=0.0024) were strong positive predictors for RRVA. Conclusions High LDL and low HDL levels were predictors for RRVA, suggesting that LDL levels should be as low as possible before PDDI is initiated. Calcification of 270° in the lesion on IVUS was a strong predictor for RRVA. Therefore, these calcifications should be debulked as much as possible using a debulking device before DCB. Additionally, overlapping of two stents was the strongest predictor for RRVA, and should thus be avoided. High LDL, low HDL, extensive calcification, and overlapping stents were predictors for RRVA. Appropriate management strategies should be implemented to mitigate these risk factors