Endovascular threatment of thrombosed arteriovenous fistulae: Mid and long term outcomes

Patent hemodialysis access is essential for patients with end-stage renal failure. Although autogenous arteriovenous hemodialysis access has proven advantages compared to graft fistula, both types of fistulas lose their function in time and need complex radiological or surgical interventions, which means hospitalization and cause-related morbidity. The most common cause of access dysfunction is trombosis, which is often secondary to decrease in flow. Major reason for thrombosis is venous stenosis. Other reasons are high-pressure compression after dialysis, hypotension, hypovolemia, sleeping position, hypercoagulability and arterial stenosis. Surgical procedures including segmental resection or creating a new fistula in addition to thrombectomy had been first choise until resent times for thrombosed homodialysis access. İn the last decade, endovascular treatment of thrombosed access including local or systemic pharmacological treatment, mechanical thrombectomy and stenting has achieved acceptable patency rates compared to the surgical techniques. İn this study we aimed to compare patency rates of thrombosed arteriovenous fistulas treated with endovascular treatment techniques to the literature and contribute our experiences with large patient population to the literature. This study is a retrospective and all patients who admitted to our department with fistula problem caused by thrombosis between 2000 and 2013 were included to the study. Patients with immature fistula, short term follow up less than 3 months, central vascular problems were excluded. Patients referred from other department or directly visited interventional radiology department due to the fistula problem were primarily evaluated with color doppler ultrasonography by an interventional radiologist. After confirming the diagnosis of thrombosis, most patients required balloon angioplasty. Mechanical thrombectomy procedures was performed in addition to pharmacological treatment of thrombosed arteriovenous fistula. İn some cases, Arrow Trerotola thrombectomy device was used and some cases required stenting. To calculate the patency rates "Kaplan-Meier survival analysis" technique was used. And Log-rank test was used to calculate diffrences in survival. İn our study autogenous fistula has 1 year primary and secondary patency rates of 66% and 85%, and graft fistula has 1 year primary and secondary patency rates of 63% and 85%, respectively. Also thrombosed autogenous arteriovenous fistula has greater primary patency durations compared with graft fistulas, which is statically significant(p<0.05). İn conclusion, thrombosed arteriovenous fistulas treated with endovascular treatment prosedures have patency rates comperable with the literature. Endovascular treatment of thrombosed fistulas is an effective and safe method that is alternative to surgical modalities. After endovascular teratment, thrombosed autogenous fistulas have greater patency rates without any additional intervention compared to graft fistulas.