Purpose: We evaluated our early experience with the transrenal fixation of
aortic stent-grafts to determine the efficacy of this procedure and its eff
ects on renal artery patency and hemodynamics.
Methods: Twenty-eight patients (22 men) had endoluminally placed modular bi
furcated stent-grafts with a bare spring structure at the proximal end cros
sing the origin of both renal arteries; no patient with infrarenal fixation
was included for analysis. The mean age of the patients was 75 +/- 7 years
(range, 58-86 years); the mean aneurysm size was 5.8 0.8, (range, 4.7-7.2
cm). Eight patients had preoperative or intraoperative angiographic evidenc
e of renal artery atherosclerotic disease, but only four vessels had lumina
l narrowing of 50% or greater. No complications were noted during stent-gra
ft placement, and all patients have returned for follow-up visits, ranging
from 1 to 12 months (mean followup, 6 +/- 4 months). Follow-up evaluations
included clinical assessment, duplex ultrasound scan of the renal arteries
and kidneys, and computed tomographic angiography.
Results: No evidence of lobular or sublobular perfusion defects of the rena
l parenchyma was detected postoperatively. Two patients exhibited postopera
tive changes in renal artery hemodynamics-one progressing from a 30% diamet
er reduction to a greater than 60% diameter stenosis at the 12-month follow
-up visit and one with a normal renal artery preoperatively having elevated
flow velocities indicative of a greater than 60% stenosis at the 1-month v
isit. Of 19 patients with normal preoperative renal function, only one has
had persistently elevated serum creatinine levels.
Conclusion: We conclude from this experience that the transrenal placement
of open stents is safe and effectively excludes the aneurysm, potentially e
xpanding the availability of this technique to more patients with a short i
nfrarenal aortic neck. Long-term follow-up is essential to determine the ov
erall efficacy of this technique and to identify potential effects on renal
artery hemodynamics or kidney function.