Lumen diameter is associated with the patency after percutaneous angioplasty of arteriovenous fistulas

Aim: To assess the value of lumen diameter after percutaneous angioplasty (PTA) to predict functional dialysis use (FDU) of arteriovenous fistulas (AVF). Methods: We performed a retrospective study of all patients who underwent first PTA because of AVF stenosis between March 2019 and March 2021. The outcome was FDU of AVF at 6 months follow up. Independent factors of FDU were identified using multivariate regression analyses. Receiver operating characteristic (ROC) curve was performed to investigate the predictive ability of lumen diameter for FDU. Results: A total 68 patients were included into this study and the AVF of 53 cases (77.9%) were good for FDU after 6 months. The AVF age was younger in failure group than that in success group (16.1 ± 9.1 months vs 28.3 ± 20.0 months, p = 0.026). Compared with failure group, the post-PTA minimum luminal diameter (MLD) was bigger in success group (4.5 [4.0–4.5 mm] vs 5.5 mm [4.5–5.5 mm], p < 0.001). Meanwhile, the gain of lumen diameter in success group was also bigger than that in failure group (2.5 mm [2.0–3.0 mm] in failure group vs 3.0 mm [2.75–3.5 mm] in success group, p = 0.012). The residual stenosis was higher in failure group than that in success group (30% [10%–40%] vs 10% [0%−20%], p = 0.003). Logistic regression showed that AVF age and post-PTA MLD were independent predictors of FDU. ROC analysis showed that the gain of lumen diameter, post-PTA MLD and improvement of stenosis were comparable to predict FDU. For post-PTA MLD, the area under ROC curve was 0.804 (95% CI, 0.681–0.927, p < 0.001). The best cutoff is 4.75 mm, with the sensitivity and specificity was 71.7% and 80.0%, respectively. Conclusions: AVF age and post-PTA MLD were independently predictors for FDU of AVF after PTA. To get the best performance, a minimum vein diameter of 4.75 mm should be obtained after angioplasty.