RESUMO
One of the most common complication in haemodialysis patients is thrombosis of the arteriovenous fistula (AVF). Thirty-five patients with a total of 42 thromboses of the angioaccess were infused via a small needle: (i) into the feeding artery (50% of the cases); (ii) into a AVF venous segment of the arteriovenous fistula (42.8%); (iii) directly into the thrombus (7.1%), by rt-PA. After an initial pulse of 5-10 mg, according to body weight, the drug was continuously infused by a pump with the speed automatically programmed in 30 Brescia-Cimino autologous AV fistulae and 12 polytetrafluoroethylene (PTFE) grafts. A complete thrombolysis with return of bruit and thrill was obtained in 71.4% of the cases using a mean drug dose of 21 mg and an infusion time of 3.8 h. All the successful cases underwent haemodialysis via AVF on the same day. No bleeding occurred at remote sites. Local bleeding occurred in 16% of the cases; in no case was it so severe as to require the suspension of the therapy or blood transfusions. The median cumulative duration of patency after thrombolysis was 32.4 months. Respectively 21, 12 and two patients had a functioning angioaccess after 3.6, 32.4 and 36 months from the lytic approach. Failure of the treatment was not related to the patients' gender or age, AVF age, route of administration of the drug, type of vessel (natural or artificial), or delay between the discovery of the fistula occlusion and the start of the therapy. In unsuccessful cases an organic lesion of the vessels was documented by angiography or echo colour Doppler. In summary, rt-PA local infusion provides a useful means of preservation of AV fistulae and may be used as the therapy of first choice in dialysis patients without active bleeding or high bleeding risk.
