P1329STENTING VERSUS ISOLATED BALLOON ANGIOPLASTY FOR CENTRAL VEIN STENOSIS IN HEMODIALYSIS PATIENTS
Authors: Zulkarnaev Aleksei , Kardanakhishvili Zurab , Baykov Boris 
Published: June 2020

Abstract

Background and Aims
comparative analysis of the results of isolated balloon angioplasty (BA) and BA with stenting of central veins stenosis in patients on hemodialysis.

Method
A retrospective study included 62 patients with confirmed stenosis of the central veins: subclavian, brachiocephalic veins, vena cava inferior, or multiple lesions. In 39 patients, stents are not used; isolated balloon angioplasty (BA) was performed. In 23 patients we used bare metal stents.

Results
Functional primary patency (the time interval between the start of AVF using and the first endovascular intervention) did not differ in the groups – fig. 1A; HR 1.142 [95% CI 0.6875; 1.897], p = 0.5994.
The use of stents leads to increase primary patency (the time interval between the first and second endovascular interventions) – fig. 1B; HR 2.064 [95% CI 1.252; 3.404], p = 0.0017.
The use of stents allows to increase the functional secondary patency (total duration of use of the AVF) – fig 1C; HR 2.099 [95% CI 1.272; 3.463], p = 0.0016.
Secondary patency (the time interval between the first endovascular intervention and the complete cessation of the use of AVF) was higher after BA with stenting: HR 2.03 [95% CI 1.232; 3.347], p = 0.0021; fig 1D.
The use of stents allows to increase functional primary assisted patency (non-occlusive period from the start of AVF use) – fig. 1E and primary assisted patency (non-occlusive period from the first surgical intervention) – fig 1F: HR 1.936 [95% CI 1.175; 3.188], p= 0.0053 and HR 2.0 [95% CI 1.213; 3.295], p = 0.0042.
The need for open reconstructive interventions after the first BA or BA with stenting was the same 0.374 [95% CI 0.24; 0.556] and 0.45 [95% CI 0.291; 0.664] per 10 patient-months, incidence rate ratio (IRR)= 0.831 [95% CI 0.471; 1.464] р=0.521.
The need for endovascular interventions did not differ between isolated BA and BA with stenting 1.137 [95% CI 0.8913; 1.43] and 0.827 [95% CI 0.606; 1.104] per 10 patient-months, IRR=1.374 [95% CI 0.952; 1.999] p=0.09.
Total need for surgical interventions (open + endovascular) also did not differ: 1.511 [95% CI 1.225; 1.843] and 1.277 [95% CI 0.997; 1.611] per 10 patient-months, IRR 1.183 [95% CI 0.872; 1.612] p=0.2822.
We found a strong negative correlation between functional primary patency and primary patency (r = -0.627; p &lt;0.0001) – fig. 2, as well as a between functional primary patency and secondary patency in patients after isolated BA (= -0.53; p = 0.0005, respectively), but not after stenting (r = -0.351; p = 0.101 and r = -0.304; p = 0.159, respectively).
In a case of isolated BA, the success of the first intervention largely determines the secondary patency, which is expressed in a strong, statistically significant positive correlation of primary patency and secondary patency. In a case of BA with stenting, the correlation between these estimates is also statistically significant, but significantly lower.

Conclusion
1. The results of balloon angioplasty without stenting are significantly influenced by the duration of the period between the start of AVF use and the manifestation of central vein stenosis. 2. The use of stents can slightly improve the results of endovascular interventions in central vein stenosis, regardless the its time of development. 3. The use of stents leads to a moderate increase in the median patency of AVF and a significant increase in the proportion of patients with functional AVF in the late postoperative period. 4. The use of stents does not reduce the need for surgical interventions