039 - Cutting Balloon Angioplasty for Resistant Pediatric Renal Artery Stenosis: A single institutional experience

Publication Number: 39.4530

Sean Schoeman, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Alexander Fairman, The Children’s Hospital of Philadelphia, Philadelphia, PA, United States; Helena B. Morse, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Amy J. Kogon, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; Kevin E. Meyers, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Dayna Mazza, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Anne Marie Cahill, Childrens Hospital of Philadelphia, Philadelphia, PA, United States

Background: Renovascular hypertension (RVH) accounts for 5-25% of pediatric hypertension. When intrinsic to the renal artery, as with renal artery stenosis (RAS), endovascular therapy is considered after initial medical management. Conventional angioplasty is the first-line invasive treatment modality, but with resistant stenosis, cutting balloon angioplasty (CBA) may be employed.

Objective: The purpose of this study is to describe the use of CBA in the management of RVH at a tertiary children’s hospital in terms of technique, angiographic and clinical outcomes, interval renal growth, and complications encountered.

Design/Methods: Retrospective review of all patients with renovascular hypertension who underwent interventional radiology angioplasty and CBA. 30 patients (70% male; median age 7.5 years [IQR: 5.7 – 12.5] and median weight were 27.7 kg [IQR: 21 – 45.3]) were identified in 35 treatment episodes. Isolated fibromuscular dysplasia (FMD) was present in 57% (n=17), FMD + mid aortic stenosis (MAS) accounted for 23% (n=7), and 20% (n=6) had neurofibromatosis type-1 (NF-1) with or without MAS. The electronic medical record and imaging databases were reviewed for procedural data and relevant clinical and follow-up data. Initial aortogram was performed using a pigtail catheter, then the renal artery was selected with a directional catheter. In patients with persistent narrowed waist on conventional angioplasty despite selection of the optimal balloon size, cutting balloon angioplasty was performed.

Results: 37 lesions were targeted; 6 had prior balloon angioplasty. Technical success (ability of cutting balloon to traverse stenosis) rate was 89% (33/37). Angioplasty success (>30% improvement of stenosis) rate was 94% (31/33). Re-stenosis rate was 8% (3/37). There was no significant relationship between technical failure, angiographic failure or restenosis and lesion location, lesion length, or associated syndrome.

Clinical benefit – blood pressure improvement, with same or reduced antihypertensive medication requirement, or blood pressure cure – at median follow-up of 59.1 months (IQR: 37.4 – 95.2; max 172) was observed in 83% (25/30); 33% were cured and 50% improved. In patients with left-sided CBA, left renal length percentile increased significantly: median pre-CBA 57% (IQR: 12 - 88%), post-CBA 72% (IQR: 24 – 97%), p = 0.0269. There were 2 severe adverse events.

Conclusion(s): To date, this is the largest known series of CBA procedures. CBA offers a promising alternative for resistant renal artery stenoses, is technically feasible, and demonstrates clinical benefit.