Endovascular treatment of stenoses in a pediatric patient with incomplete aortic duplication, mesenteric ischemia, and renovascular hypertension

HISTOLOGIC AND MORPHOLOGIC CHARACTER OF PEDIATRIC ABDOMINAL AORTIC DEVELOPMENTAL COARCTATION AND HYPOPLASIA

OBJECTIVES

Abdominal aortic coarctation and hypoplasia are uncommon diseases, recognized most often in pediatric-aged individuals. Comprehensive studies regarding the pathologic spectrum of these aortopathies are nonexistent. This investigation was undertaken to better define the histologic and morphologic character of abdominal aortic narrowings affecting children and assess its potential relevance to contemporary clinical practice.

METHODS

Aortic specimens obtained during open operations in children being treated for symptomatic, noninflammatory abdominal aortic narrowings at the University of Michigan were subjected to histologic study following hematoxylin-eosin, Movat, Verhoeff Van Gieson, and Masson's trichrome preparations. Microscopic findings were correlated with the anatomic aortic images. In addition, a detailed review was completed of all prior reports in the English literature that included images depicting the histologic character of noninflammatory abdominal aortic narrowings in children.

RESULTS

Among a series of 67 pediatric-aged individuals undergoing open surgical interventions for abdominal aortic narrowings, eight children ranging in age from 9 months to 18 years, had adequate aortic tissue available for study. The loci of the specimens paralleled the anatomic sites of segmental coarctations observed in the entire series, with involvement of the suprarenal abdominal aorta (3), intrarenal aorta (2), and infrarenal aorta (1). Diffusely hypoplastic abdominal aortas (2) included one case of a de facto aortic duplication, represented by a channel that paralleled the narrow native aorta and gave origin to celiac artery branches, as well as the superior mesenteric and renal arteries. Concentric or eccentric intimal fibroplasia was observed in every aorta, often with internal elastic fragmentation and duplication (4). Media abnormalities included elastic tissue disorganization (3), and focal medial fibrosis (1). Organizing luminal thrombus occurred in two infants. Coexistent ostial stenoses of the celiac, superior mesenteric, or renal arteries were observed in all but the only child who having an infrarenal aortic coarctation. Neurofibromatosis-1 affected one child whose histologic findings were indistinguishable from those of the other children. Review of prior published histologic images of abdominal aortic coarctation and hypoplasia affecting children from other centers revealed a total of 14 separate reports, each limited to single case photomicrographs of which 11 exhibited intimal fibroplasia.

CONCLUSIONS

Intimal fibroplasia is a common accompaniment of developmental abdominal aortic coarctation and hypoplasia. It is posited that intimal fibroplasia, that is likely progressive in instances of abnormal shear stresses in these diminutive vessels, may contribute to less salutary outcomes following endovascular and certain open reconstructions of pediatric abdominal aortic narrowings.

Arterial reconstructions for pediatric splanchnic artery occlusive disease

OBJECTIVE

Pediatric splanchnic arterial occlusive disease is uncommon and a rare cause of clinically relevant intestinal ischemia. This study was undertaken to better define the clinical manifestations and appropriate treatment of celiac artery (CA) and superior mesenteric artery (SMA) occlusive disease in children.

METHODS

Clinical courses of 30 consecutive children undergoing operations for splanchnic arterial occlusive disease at the University of Michigan from 1992 to 2017 were retrospectively analyzed.

RESULTS

Vascular reconstructions were performed for splanchnic arterial disease in 18 boys and 12 girls, 1.5 to 16 years of age (mean, 7.5 ± 4.1 years). Isolated splanchnic arterial disease was uncommon (2 children), being more often associated with abdominal aortic coarctations (19 children) or ostial renal artery stenoses (25 children). Primary splanchnic arterial reconstructions (30) included aortic reimplantation of SMAs (15) or celiacomesenteric arteries (2), aortoceliac and aortomesenteric bypasses (7), reimplantation of the CA as a patch over the stenotic SMA orifice (3), and patch angioplasty of the CA (2) or SMA (1). There was no perioperative mortality. Two groups (I and II) were identified for study. Group I children (14) experienced symptomatic intestinal ischemia, manifested by various combinations of chronic postprandial abdominal discomfort (14), ischemia-related intestinal bleeding (2), or failure to thrive (4). Four children in group I became symptomatic after known CA and SMA occlusive disease was left untreated at the time they underwent earlier interventions for renovascular hypertension. Seven secondary redo interventions were undertaken for recurrent symptoms in six group I children. Only one major periprocedural complication occurred: segmental colon infarction. The assisted patency rate of reconstructed arteries in group I children was 93%, and intestinal ischemic symptoms resolved in every child. Group I follow-up from the most recent splanchnic arterial reconstruction averaged 4.3 years. Group II children (16) without manifestations of intestinal ischemia underwent prophylactic splanchnic arterial reconstructions in concert with combined aortic and renal artery procedures (11), isolated abdominal aortic reconstructions (3), or renal artery reconstructions alone (2). Group II children experienced no major perioperative morbidity and remained asymptomatic postoperatively, and none required secondary splanchnic artery interventions. Group II follow-up averaged 7.4 years.

CONCLUSIONS

Pediatric splanchnic artery occlusive lesions are often associated with developmental aortic and renal artery occlusive disease. Carefully conducted therapeutic and prophylactic reconstructive procedures are appropriate in children having splanchnic arterial occlusive disease.

Intestinal ischemia in neonates and children

The article reviews the intestinal ischemia theme on newborn and children. The intestinal ischemia may be either acute - intestinal infarction (by vascular obstruction or by reduced mesenteric blood flow besides the occlusive mechanism), either chronic.

In neonates, acute intestinal ischemia may be caused by aortic thrombosis, volvulus or hypoplastic left heart syndrome.

In children, acute intestinal ischemia may be caused by fibromuscular dysplasia, volvulus, abdominal compartment syndrome, Burkitt lymphoma, dermatomyositis (by vascular obstruction) or familial dysautonomia, Addison’s disease, situs inversus abdominus (intraoperative), burns, chemotherapy administration (by nonocclusive mesenteric ischemia). Chronic intestinal ischemia is a rare condition in pediatrics and can be seen in abdominal aortic coarctation or hypoplasia, idiopathic infantile arterial calcinosis.