Ruptures occurred in 10% of transposed fistulae and in 2.8% of grafts.
SEATTLE—Percutaneous transluminal angioplasty (PTA)-induced rupture rates are higher in fistulae than grafts, researchers reported here at the Society of Interventional Radiology annual meeting.
The higher rates are due entirely to the effect of PTA on transposed fistulae, according to the investigators.
“We found that the rupture rate for these superficialized and mobilized fistulae to be almost four times higher than what we saw for grafts,” said investigator Scott Trerotola, MD, chief of interventional radiology at the Hospital of the University of Pennsylvania in Philadelphia.
PTA-induced venous rupture is a well-documented, common complication of hemodialysis access interventions, he said. However, in light of increasing fistula prevalence in the United States, he and his colleagues wanted to determine if venous rupture rates and management differed between fistulae and grafts.
Using a database that spanned five years (July 2001 to July 2006), the investigators identified venous ruptures during hemodialysis PTA. They found 75 in 69 patients (46 female). The patients had a mean age of 63 years (range 31-88).
The researchers divided access types into transposed fistulae, non-transposed fistulae, and grafts, and looked at rupture rates, proportion of successful treatments, and type and number of treatments (e.g., balloon tamponade, stent, covered stent).
The rupture rate was 5.6% among fistulae compared with 2.8% among grafts, the study found. In transposed fistulae, the rate was 10%, almost four times that of grafts. The non-transposed fistula rupture rate was 3.9%. The difference in rates between non-transposed fistulae and grafts was not significant. Study findings were presented by lead investigator Noah Kornfield, a second-year medical student working with Dr. Trerotola.
Dr. Trerotola said it was important to note that the study found the success rates for treatment of rupture were very similar among the various groups. It was 67% in the fistula group as a whole, 68% in the transposed fistula group, 65% in the non-transposed fistula group, and 72% in the graft group.
“This is the first study to really look at these issues in different types of fistulae and their response to angioplasty,” Dr. Trerotola said. “Our concern is that certain fistulae may have high complication rates or poor patency rates and so perhaps they should not be promoted as heavily as they are. However, these findings are preliminary and we have not yet addressed the patency issue.”
The study also showed that stents were required to treat rupture more frequently in patients with grafts than in those with fistulae (52% vs. 10%), and more treatments overall were required in the graft group.
The study found that 46% of graft ruptures were successfully treated with balloon tamponade alone. Only 14 of the 26 graft ruptures required stents. In the fistula group, 77% of ruptures were treated successfully with balloon tamponade alone. Three ruptures required stenting, two resolved with manual pressure, and one required no treatment.
“I am a proponent of the Fistula First Initiative. It is the right thing to do. We need to have more fistulae in this country,” Dr. Trerotola said. “However, I don’t think we should put a fistula in every single person. Nephrologists should be aware that in patients with superficialized and transposed fistulae, they cannot expect the outstanding outcomes that have been reported for in situ fistulae.”