Background: Stent implantation of renal stenosis (RS) has been reported on extensively; this technique is perceived as superior to balloon angioplasty alone and less invasive than surgical revascularization. With the development of new accessories and stents, we can now improve and optimize procedural and clinical results. In this pilot study, we tested an alternative minimally invasive approach for renal stenting: the transradial artery catheterization (TAC) and a 6 French (Fr) system for stenting.
Methods: In this feasibility study, we enrolled patients with RS uncontrolled hypertension and/or chronic renal insufficiency. After assuring good dual blood supply (Allen test), TAC was attempted. The guiding catheters chosen for stenting were 6 Fr (0.70 ) Zuma 2 (Medtronic AVE, Santa Rosa, California). The selection of the guiding catheter was performed with respect to back-up support and coaxial alignment. RS were crossed with a coronary extra support guidewire (0.0.14 mailman, Boston Scientific/Scimed, Maple Grove, Minnesota). A balloon angioplasty before stenting was performed only in presence of subocclusive calcified stenosis, otherwise direct stenting was performed. We used low profile stents (12 16 mm LP Sulzer stent, IntraTherapeutics Inc., Minnesota) manually crimped on monorail balloon (5.0 6.0 mm x 20 mm). Immediately after completion of the procedure, the sheath was removed and a selective radial artery compression device was used for hemostasis. Patients were not restricted to bedrest, but were discharged the following day.
Results: There were 25 patients in the study population. Procedural indications were poorly controlled hypertension in 15/25 patients and/or preservation of renal function in 10/25 patients. Procedural success was obtained in 27/27 lesions (100%). Direct stenting was performed in 24/27 stenosis; predilatation was necessary in 3/27. We used 1 stent per lesion. The mean fluoro time was 7 5 minutes/lesion and mean procedural time was 14 5 minutes/lesion. No procedural and clinical complications occurred during the procedures upon the discharge.
Conclusions: Our results confirmed the safety of this approach in the treatment of RS. The devices used in the study were those traditionally used for coronary procedures. The adoption of these materials and techniques have simplified the procedure and has permitted a reduction of fluoro and procedural time. An additional advantage has been the passive achievement of hemostasis by pressure devices reducing the workload of nursing and medical staff with elimination of bleeding complications that allowed immediate post procedural ambulation.