1. Pediatric Renal Artery
Stenosis
“Efficacy of Endovascular Interventions”
Matt Hawkins, MD
Assistant Professor – Emory University SOM

2. Introduction
• 1-2% of children have sustained HTN
• RAS = 5-25% of pediatric HTN cases
• Renal scarring, aortic coarctation,
glomerular disease, and adrenal
hypersecretion are the most common cause
• Renal artery stenosis (RAS) accounts
for ~10% of HTN cases in kids.

3. Introduction
• Renal artery stenosis (RAS) accounts
for ~10% of HTN cases in kids.
• Dominant etiologies include:
• Fibromuscular dysplasia (FMD)
• Neurofibromatosis 1
• Williams syndrome
• Mid-aortic syndrome

4. RAS in kids
• 86% of stenoses in 1st or 2nd order branches
• Stenoses in multiple 1st/2nd order branches = 32%
• Bilateral disease = 30%
• Intraparenchymal diasese = 30% (aneurysms, collaterals,
stenoses, etc.)

5. RAS in kids

6. FMD in adults
• 29 women; 38 interventions (17 yr retrospective)
• Technical success = <30% stenosis
• 8% complication rate
• 72% improved or cured (SBP<140)
• Primary and assisted primary patency = 66%
and 76% at 5 years

7. FMD in adults
• 59 patients (17 year retrospective)
• 95% technical success
• 34% needed repeat angioplasty
• Cure = 24%
• Improvement = 39%

8. FMD in adults

9. FMD in adults
• 35 patients; 43 procedures
• 100% technical success
• Primary and primary assisted patency =
(95%, 71%, 50%) and (100% all) at 1, 5, & 9
years respectively
• 6% cure; 63% improved

10. FMD in adults
• Meta-analysis of 50 studies of PTA for FMD
• Technical success = 88.2%
• Complication rate = 11.8% (major 6.3%)
• Cure = 35.8%

11. Renal artery stenosis in kids

12. Renal artery stenosis in kids
48 procedures in 33 patients

13. Renal artery stenosis in kids

14. Renal artery stenosis in kids
• 19 patients; 32 treated lesions
• Technical success = 91%
• 39% cure; 17% improvement; 44% failure
• Cutting balloons successful in 5 of 7 uses
• 1 renal artery perforation; 1 accelerated
hypertension; 1 groin hematoma

15. Renal artery stenosis in kids
• 22 patients, 34 procedures
• 16 = Takayasu; 6 = FMD
• Technical success = 94.1%
• 27.3% cure; 45.5% improvement
• 41% restenosis (3-47 month range)
• 1 minor complication

16. What about cutting balloons
• Complications include
• Dissection (3.6% in coronary studies)
• Rupture
• Renal artery thrombosis

17. What about cutting balloons

18. What about cutting balloons

19. Literature Summary
• Cure 1/3, Improve 1/3, Fail 1/3
• Safe procedure
• Technically successful >90% of the time
• ~40% will re-stenose w/in 5 years
• Avoid stents in children
• Cutting balloons can be helpful with
resistant stenoses when used cautiously
• Should we look for extra-renal disease in
these kids?

20. Howdo we do renal
artery
angioplasty?

21. Equipment
• 4F 45cm sheath
• 0.014 wire (BMW/RunThrough)
• 2.5F Cantata & 0.014 Synchro (if needed)
• 1-2 cm Sterling monorail balloons
• Flextome cutting balloons (if needed)

22. Medications
• Heparin 100U/kg
– Before angioplasty
– 10-20U/kg every 45 minutes thereafter
• Nitroglycerin 1mcg/kg (optional)
• ASA 325mg loading dose (if stenosis is known
prior to case)

23. Post-Procedure Care
• Leg straight 2-3 hrs (if 4F sheath)
• ASA 81 mg for 6 months
• If cutting balloon used:
– Overnight ICU admission on heparin drip
– Doppler ultrasound next day
– ASA 81mg for 6 months

24. Case 1

25. Case 1

26. Case 1

27. Case 2

28. Case 2

29. Case 2
Stenosis Post-stenotic dilation

30. Case 2
Stenosis Post dilation

31. Case 2 (second try)

32. Case 2
Right kidney

33. Case 2

34. Case 2

35. Case 2

36. Case 2

37. Case 2
PRE
POST

38. Case 2
POST

39. Case 2 (3rd time is a charm)

40. Case 2

41. Case 2

42. Case 2

43. Matt Hawkins, MD
@MattHawkinsMD
matt.hawkins@emory.edu