Morphological Lesion Types Are Associated with Primary and Secondary Patency Rates after High-Pressure Balloon Angioplasty for Dysfunctional Arteriovenous Fistulas

Abstract

<b><i>Background:</i></b> Neointimal hyperplasia (NIH) is believed to be the main reason for arteriovenous fistula (AVF) dysfunction, but other mechanisms are also recognized to be involved in the pathophysiological process. This study investigated whether different morphological types of AVF lesions are associated with the patency rate after percutaneous transluminal angioplasty (PTA). <b><i>Methods:</i></b> This retrospective study included 120 patients who underwent PTA for autogenous AVF dysfunction. All the cases were evaluated under Doppler ultrasound (DU) before intervention and divided into 3 types: Type I (NIH type), Type II (non-NIH type), and Type III (mixed type). Prognostic and clinical data were analyzed by Kaplan-Meier analysis and the Cox proportional hazards model. <b><i>Results:</i></b> There was no statistical difference in baseline variables among groups, except for lumen diameter. The primary patency rates in Type I, Type II, and Type III groups were 78.4, 93.2, and 83.2% at 6 months and 59.5, 84.7, and 75.5% at 1 year, respectively. The secondary patency rates in Type I, Type II, and Type III groups were 94.4, 97.1, and 100% at 6 months and 90.5, 97.1, and 94.7% at 1 year, respectively. The Kaplan-Meier curve showed that the primary and secondary patency rates of Type I group were lower than those of Type II group. Multivariable Cox regression analysis demonstrated that postoperative primary patency was correlated with end-to-end anastomosis (hazard ratio [HR] = 2.997, <i>p</i> = 0.008, 95% confidence interval [CI]: 1.328–6.764) and Type I lesion (HR = 5.395, <i>p</i> = 0.004, 95% CI: 1.730–16.824). <b><i>Conclusions:</i></b> NIH-dominant lesions of AVF evaluated by DU preoperatively were a risk factor for poor primary and secondary patency rate after PTA in hemodialysis patients.

Long-Term Efficacy of Ultrasound-Guided Percutaneous Transluminal Angioplasty for Arteriovenous Fistula Outflow Stenosis Caused by Venous Valve

“…In the study by Suemitsu et al, compared to patients with IH stenosis, those with shrinking lumen stenosis were found to be at a higher risk of restenosis (HR 2.05, 95% CI: 1.25–3.36, p = 0.005 ), while those with VVRS were at a lower risk of restenosis (HR 0.19, 95% CI: 0.04–0.79, p = 0.023 ) [ 6 ]. Chen et al [ 12 ] also demonstrated that the stenosis caused by IH had dismal primary patency compared to stenosis caused by other initial reasons. Compared to our previous study [ 13 ], which consisted of 96 patients who developed juxta-anastomotic stenosis or occlusion caused by IH, this study found a relatively better 6 months (86.0 vs. 77.4%), 1 year (69.4 vs. 53.6%), 2 years (47.5 vs. 37.0%), and 3 years (35.3 vs. 33.2%) primary patency rates.…”

Comparison of ultrasound features and lesion sites in dysfunctional arteriovenous fistula

“…Chen et al. [ 5 ] claimed that the primary patency and secondary patency of AVF after PTA in the NIH group were significantly lower than those in the non-NIH group; however, they did not report the PTA times before the study. Suemitsu et al.…”

“…Meanwhile, all studies claimed that different ultrasound features of AVF stenosis were valuable for choosing treatment strategies. For example, drug-coated balloons may be beneficial in the NIH-dominant group owing to their antiproliferative actions, and stents may be chosen for constriction restenosis [ 5 , 6 ]. Sonographic classification studies attempted to refine the morphological features of AVF lesions and link them to the pathophysiological mechanisms of AVF stenosis.…”

“…The intima thickness was measured at the thickest part of the stenotic region of a single vein. Based on a previous study, the intimal thickness was ≤0.6 mm at the stenosis site in the non-intima-dominant group and >0.6 mm in intima-dominant group [ 5 ]. The venous valve obstruction group included venous valve dysfunction-induced stenosis.…”

“…Recently, vascular ultrasound has become increasingly common for PTA application, with the advantages of being highly sensitive, reproducible, and noninvasive for the evaluation of vascular lesions. In recent years, new AVF stenosis classifications based on ultrasound features have been explored [ 5 , 6 ]. These classifications are focussed on vascular neointimal hyperplasia (NIH) and correlate NIH with the histological features and pathophysiological mechanisms of AVF stenosis, suggesting that AVF stenosis is not homogeneous and that different stenosis features may influence treatment strategies [ 5–8 ].…”