STUDYING THE EFFECTIVENESS OF PERCUTANEOUS TRANSLUMINAL ANGIOPLASTY IN SALVAGING DYSFUNCTIONAL HEMODIALYSIS ARTERIOVENOUS FISTULAS: INITIAL INSIGHTS FROM NORTHEAST INDIA.

Percutaneous transluminal angioplasty (PTA) is a standard and effective treatment for dysfunctional arteriovenous fistulas (AVFs) used for haemodialysis, demonstrating high technical and clinical success rates. Studies have indicated that PTA can enhance blood flow and help maintain fistula patency, although reintervention rates may be high. However, there is currently no research conducted in North East India on this topic. The aims and objectives of this study are to analyse the outcomes of PTA among our patients.

This prospective observational study involved 60 patients who underwent percutaneous transluminal angioplasty (PTA) for dysfunctional arteriovenous fistulas (AVFs). The study was conducted from January 2023 to June 2025 at a single center in Northeast India. PTA was performed by a trained interventional nephrologist in the catheterization lab of a tertiary care hospital. Patients were selected for PTA based on clinical examinations of their AVFs, which indicated inflow or outflow lesions, immature AVFs, a history of prolonged bleeding after dialysis, blood flow rates of less than 200 ml/min, or high venous pressures exceeding 200 mmHg. Written consent was obtained from all patients, during which the benefits, risks, and alternative options were explained. Case selection was done randomly. Patients were excluded from the study if they had extensive clotting, large or multiple aneurysms, or a non-functional (dead) AVF. The procedure was conducted in the catheterization lab using fluoroscopy and contrast media under local anesthesia while maintaining sterile conditions. The equipment used for the procedure included access needles (Jelco) and vascular sheaths (6-11 Fr), catheters (multipurpose and support), guidewires (ranging from 0.035’’ to 0.014’’ with regular, stiff-tip, and straight designs), and angioplasty balloons (5-16 Fr, normal and high pressure). AVFs were accessed by cannulating the radial artery, fistula vein, and femoral vein for any central vein lesions. A standard PTA protocol was followed, utilizing both low-pressure balloons (Mustang, Chameleon by Medtronic) and high-pressure balloons (Conquest). Cutting balloons and drug-eluting balloons were not employed due to their high costs. Heparin was not routinely administered. Balloon inflation times varied from 30 seconds to 2 minutes. Pain relief was achieved through a combination of fentanyl and midazolam.

Outcome parameters included fistula patency, defined as the time from intervention to the first occurrence of failure (including thrombosis, restenosis, or abandonment or death), as well as median time to failure and primary failure rates. Patients were followed up on an outpatient basis, with monthly visits to the respective dialysis unit. Data analysis was performed using Microsoft Excel.

A total of 61 patients were enrolled in the study from January 2023 to June 2025. The mean age of the participants was 58.47 years, with a standard deviation of 13.51years (age range: 17 to 85 years). The male-to-female ratio was 41:20. The underlying kidney diseases among the patients were as follows: Diabetes in 36 patients (59%), Systemic Lupus Erythematosus (SLE) in 4 patients (6.5%), Hypertension in 9 patients (14.8%), and Chronic Kidney Disease (CKD) of unknown etiology in 12 patients (19.7%).

The distribution of arteriovenous fistulas ( AVFs, N=60) was as follows:

- Brachio-basilic: 3 (5%)

- Radiocephalic: 31 (51%)

- Brachiocephalic: 25 (41%)

- Ulnar-basilic: 1 (1.5%)

- Central vein stenosis-1(1.5%)

The distribution of access sites used was:

- Radial artery: 19 (31.2%)

- Brachial artery: 1 (1.6%)

- Fistula vein: 20 (32.7%)

- Femoral vein: 8 (13.2%)

- Combined approach (Radial artery and outflow vein): 13(21.3%)

Distribution of lesions: A single lesion was observed in 38 patients (62.4%), while multiple lesions were found in 23 patients (37.6%).

Table: Distribution of lesions

[JAS-Juxta anastomotic stenosis, CAS-Cephalic arch stenosis, CVS-Central vein stenosis, BCV-Brachiocephalic vein, SCV-Subclavian vein, BL-Bilateral]  

Outcome of Percutaneous Transluminal Angioplasty (PTA):

Out of 61 patients, 6 (10%) had tight central vein stenosis (total occlusion) that could not be negotiated. Three patients (5%) with immature fistulas experienced rupture of the vein, leading to subsequent infection. PTA was unsuccessful in 4 patients (6.5%) due to clotting in 2 cases and extensive lesions in the other 2. There was a primary failure requiring an alternative mode of access in 14 patients (26%).

 PTA was successful in the remaining 46 patients (74%). During the study period, 6 patients (9.8%) died, including two who passed away in the post-procedure phase due to stroke (1 patient) and acute coronary syndrome (1 patient). A total of 23 patients (34.7%) had active arteriovenous fistulas (AVFs), and 1 patient was lost to follow-up. Additionally, 17 patients (37%) experienced a recurrence of stenosis, with a median time to recurrence of 7.0 months (ranging from 2 to 19 months). The average patency time after PTA was 8.05 months, and the patency rates after PTA at 3 months (n=37) and 6 months (n=29) were 86.4% and 68.9%, respectively.

Repeat PTA was successfully performed in 5 patients, and 7 patients required conversion to tunnelled central catheter (TCC). One patient underwent kidney transplantation.

Drawbacks of the study: Sample size is low. Declotting was not performed. Procedure performed by single nephrologist who is in early phase of experience

Percutaneous transluminal angioplasty for dysfunctional arteriovenous fistulas (AVFs) has a high success rate, with a mean time until lesion recurrence of 8.0 months. The patency rate following PTA is quite satisfactory, with rates of 86.4% at 3 months and 68.9% at 6 months. Additionally, multiple lesions are common in our region.

[Content of the abstract was presented at AVAATAR, India 2025, but with smaaler number patinets]