Selective renal embolisation for renovascular hypertension?

Severe hypertension due to renal polar artery stenosis in an adolescent treated with coil embolization

A 12-year-old boy presented with severe arterial hypertension due to a severe subsegmental renal artery stenosis. Treatment consisted of selective embolization of the stenosed polar artery, which resulted in near normalization of the arterial pressures. Renal artery stenosis should always be considered, even in young adolescents, as a cause for arterial hypertension. Only selective angiography was able to demonstrate the subsegmental artery stenosis in this patient.

Renovascular hypertension and intrarenal artery aneurysms in a preschool child

Renovascular hypertension from renal artery aneurysmal formation is a rare complication of fibromuscular dysplasia. Few data exist to direct the management of intrarenal artery aneurysms in pediatric patients. We report the presentation, diagnosis and management of renovascular hypertension and intrarenal aneurysmal disease in a preschool child.

Renovascular hypertension in children

Renovascular disease is an uncommon but important cause of hypertension in children. It is usually diagnosed after a long delay because blood pressure is infrequently measured in children and high values are generally dismissed as inaccurate. Many children with renovascular disease have abnormalities of other blood vessels (aorta, cerebral, intestinal, or iliac). Individuals suspected of having the disorder can be investigated further with CT, MRI, or renal scintigraphy done before and after administration of an angiotensin-converting-enzyme inhibitor, but angiography is still the gold standard. Most children with renovascular disease will need interventional or surgical treatment. Endovascular treatment with or without stenting will cure or reduce high blood pressure in more than half of all affected children. Surgical intervention, if needed, should be delayed preferably until an age when the child is fully grown. Modern treatment provided by a multidisciplinary team of paediatric nephrologists, interventional radiologists, and vascular surgeons offers good long-term treatment results.

Renal embolization as an alternative to surgical nephrectomy in children

PURPOSE

Complete renal embolization may be an alternative to surgical nephrectomy. The indications for renal embolization do not differ from those for surgical nephrectomy, but the less invasive nature of the technique is a major advantage. Few case reports are available in the pediatric age group. Our experience showed that complete renal embolization was feasible in pediatric patients with results comparable to those obtained in adults.

MATERIALS AND METHODS

Twelve pediatric patients underwent 14 renal embolizations. The indications for embolization were as follows: (1) severe hypertension in 7 patients with end-stage renal failure; in these cases, a unilateral native nephrectomy was recommended prior to renal transplantation; (2) end-stage hydronephrosis in 3 patients with moderate hypertension or recurrent urinary infection; (3) nephrotic syndrome in 1 patient; or (4) ablation of an irreversibly rejected renal allograft in 1 patient. The embolization was performed under epidural anesthesia in 10 patients and under general anesthesia in 2 patients, by means of a polyvinyl alcohol injection with hemostatic gelatin powder and placement of coils. Postembolization course was followed.

RESULTS

The embolization was successful in all 12 patients. In 1 patient, the procedure had to be repeated as a small accessory artery had revascularized the upper pole. In another patient, the procedure was bilateral in 2 separate sessions. In 10 patients, severe flank pain required narcotic analgesia. Two patients had fever. None had hypertension peaks. Median hospital stay was 4 days. At mean follow-up of 16 months, the results were stable.

CONCLUSION

Renal embolization can avoid surgical nephrectomy also in pediatric patients. The advantages are less morbidity and shorter hospital stay. Our results in the short and medium term were equal to those of surgical removal. The procedure appeared to be safe and minimally invasive.

Interventional radiology for renovascular hypertension in children

Pediatric renovascular hypertension is an uncommon but important clinical problem. Atherosclerosis is rare in children, who typically suffer from fibromuscular dysplasia, neurofibromatosis type 1, Williams syndrome, or certain other rare conditions. Children with renovascular disease often have involvement of other arteries including the aorta and mesenteric and cerebral vessels. The pediatric interventional radiology service has a vital role in the diagnosis, evaluation, and treatment of renovascular hypertension. Renal vein renin sampling appears to be more useful in children than in adults, because their arterial disease is more often bilateral and segmental. Diagnostic angiography is still superior to less-invasive methods of imaging the renal arteries, especially the smaller branches. Interventional options include angioplasty, stenting, and ethanol ablation. Angioplasty is almost always technically successful and usually gives a worthwhile clinical improvement. Stenting is only used in children when angioplasty fails. Ethanol embolization may be appropriate in children with focal renin-producing areas that are untreatable by angioplasty.