Primary congenital abdominal aortic aneurysm: a case report with perinatal serial follow-up imaging

Microsurgical and Endovascular Management of Congenital Iliac Aneurysms in the Neonatal Period: Two Cases and a Literature Review

Introduction

Congenital aneurysms of major arteries are very rare diagnoses and prognosis can be poor if treatment is not initiated rapidly. This is the presentation of two cases of infants with congenital iliac aneurysms who underwent treatment in the neonatal period. The report then proceeds with a literature review of paediatric iliac aneurysms.

Report

Case 1: A female neonate was diagnosed antenatally with right common iliac (CIA) and internal iliac (IIA) artery aneurysms. Embolisation on day of life (DOL) eight was impossible because of partial thrombosis. The infant was subsequently observed for several months and the aneurysm was injected percutaneously with thrombin on DOL 78. A small residual aneurysm was coil embolised at five months of age. Satisfactory results were observed at one year follow up. Case 2: A female neonate was diagnosed antenatally on routine third trimester ultrasound with voluminous, bilateral CIA aneurysms. The patient underwent surgery on DOL 9 for aneurysm resection and microsurgical vascular reconstruction. The intervention was successful with triphasic flow through the anastomoses on colour Doppler ultrasound at six week follow up.

Discussion

Ten cases of congenital iliac aneurysms have been reported previously, with just two diagnosed in the neonatal period and eight undergoing surgical intervention. Definitive management to avoid aneurysm rupture or thrombosis should be timed carefully, and sometimes delayed with watchful waiting, to maximise success and minimise complications. Surgery is the key treatment modality, but endovascular intervention can be considered in selected cases. Congenital iliac aneurysms should be addressed at the safest time for the patient. Following resection, primary microvascular anastomosis is the ideal reconstructive technique, but other options for neonates have been described. Endovascular treatment should be considered for anatomically amenable saccular aneurysms.

Neonatal Microsurgical Repair of a Congenital Abdominal Aortic Aneurysm with a Cadaveric Graft

Congenital abdominal aortic aneurysms (AAA) are an extremely rare entity. We present the case of a female fetus diagnosed with an AAA on routine prenatal ultrasound. A postnatal computed tomography angiogram revealed an infrarenal AAA with a narrow proximal neck. Surgery was performed on day of life 14 using a cadaveric femoral artery graft. The proximal anastomosis was performed under the microscope given the severity of the aortic stenosis and the proximity of the renal arteries. The patient's postoperative course was uneventful and she is developing normally 1 year after surgery. The graft remains permeable, albeit with evidence of proximal and distal stenosis and graft calcification on imaging.

Diagnosis and treatment of congenital abdominal aortic aneurysm: a systematic review of reported cases

Background

Congenital abdominal aortic aneurysm (AAA) is distinctly rare in infants and children and carries a high mortality rate. Our objective was to summarize the experience of the diagnosis and treatment in patients with congenital AAA.

Methods

Reported cases of congenital AAA published prior to November 8, 2014, were identified through PubMed, EMBASE, Web of Science, and reference lists. All selected cases were evaluated for main clinical characteristics.

Results

Twenty-six cases of congenital AAA were identified in the English language literature. Congenital AAA occurred primarily in children under three years old, but it was also found in young adults and fetuses. With regards to the localization, the great majority of congenital AAA was infrarenal AAA. The majority of the AAA patients lacked specific symptoms, and a painless pulsatile abdominal mass was the most common clinical presentation. The diagnosis of AAA was based on ultrasound scanning in twenty-five cases, multi-slice spiral computed tomography angiography (MSCTA) in sixteen cases, and magnetic resonance angiography (MRA) in nine cases. Histopathological analyses were available in seven cases. Seven patients received conservative management. Surgical treatment was performed in seventeen cases, and open repair with an artificial graft was the main surgical intervention. The mortality associated with congenital AAA was high (30.76%). Ruptured aneurysm and renal failure were the main causes of death.

Conclusions

Good outcomes can be achieved in children with early identification of congenital AAA and individualized surgical repair with grafts.

Quantitative anatomy of the growing abdominal aorta in human fetuses: an anatomical, digital and statistical study

Background

Advances in perinatal medicine have required an extensive knowledge of fetal aorto-iliac measurements. The present study was performed to compile reference data for dimensions of the abdominal aorta at varying gestational ages.

Material/Methods

Using the methods of anatomical dissection, digital-image analysis (Leica QWin Pro 16 system), and statistical analysis (Student’s t-test, one-way ANOVA, post-hoc RIR Tukey test, regression analysis, and Wilcoxon signed-rank test), the growth of length (mm), proximal and distal external diameters (mm), and volume (mm³) of the abdominal aorta in 124 (60 male, 64 female) spontaneously aborted human fetuses aged 15–34 weeks was examined.

Results

No significant male-female differences were found. The length ranged from 9.35±1.24 to 36.29±4.98 mm, according to the linear function y=−14.596+1.519 × Age ±2.639 (R²=0.92; p<0.0001). The proximal external diameter varied from 1.18±0.25 to 5.19±0.49 mm, according to the linear pattern y=−2.065+0.212 × Age ±0.348 (R²=0.92; p<0.0001). The distal external diameter increased from 1.03±0.23 to 4.92±0.46 mm, in accordance with the linear model y=−2.097+0.203 × Age ±0.351 (R²=0.92; p<0.0001). Both length and proximal external diameter of the abdominal aorta indicated a proportionate evolution, because the length-to-proximal external diameter ratio was stable, following the linear function y=7.724–0.017 × Age ±0.925. The abdominal aorta volume ranged from 9.6±4.5 to 740.5±201.8 mm³, given by the quadratic function y=911–101 × Age +2.838 × Age² ±78 (R²=0.89; p<0.0001).

Conclusions

There are no significant differences between males and females for morphometric parameters of the abdominal aorta. The abdominal aorta grows linearly in both length and diameters, and parabolically in volume. These detailed morphometric data of the abdominal aorta provide a database for intra-uterine echographic examinations in the early diagnosis, monitoring and management of aorto-iliac malformations.

The normal growth of cross-sectional areas of the aorto-iliac segment in human fetuses - an anatomical, digital, and statistical study

BACKGROUND

The intraluminal size of the aorto-iliac segment is relevant in both the clinical and echographic settings. The aim of this study was to compile both the absolute and relative age-specific reference intervals for cross-sectional areas (CSAs) of the aorto-iliac segment.

MATERIAL/METHODS

Using the methods of anatomical dissection, digital-image analysis (Leica QWin Pro 16) and statistical analysis (Student's t test, one-way ANOVA, post-hoc RIR Tukey test, linear regression), the growth in CSA (in mm2) of the abdominal aorta, the common, external, and internal iliac arteries in 124 (60 males, 64 females) spontaneously aborted human fetuses aged 15-34 weeks was examined.

RESULTS

No significant sex differences were found. In the age range of 4-9 months, the distal CSA of the abdominal aorta ranged from 0.87±0.34 to 19.18±3.36 mm2. The CSA of the common iliac artery varied from 0.37±0.22 to 4.30±1.54 mm2 on the right, and from 0.36±0.16 to 3.80±1.44 mm2 on the left. The sum of the CSAs of the right and left common iliac arteries grew proportionately to the distal CSA of the abdominal aorta; the latter being significantly larger than the former. On both sides, however, the CSA of the internal iliac artery was approximately twice that of the external iliac artery. Between the ages of 4 and 9 months, the CSA of the external iliac artery ranged from 0.10±0.06 to 1.32±0.52 mm2 on the right, and from 0.08±0.03 to 1.19±0.42 mm2 on the left. The CSA of the internal iliac artery increased from 0.23±0.14 to 2.59±1.22 mm2 on the right, and from 0.21±0.14 to 2.27±1.11 mm2 on the left. Bilaterally, the sum of the CSAs of the internal and external iliac arteries was significantly smaller than the CSA of the common iliac artery. The relative CSA of each artery decreased until the age of 6 months, after which their values were gradually increasing until the age of 9 months.

CONCLUSIONS

The aorto-iliac segment does not reveal sex differences in its cross-sectional area. The cross-sectional area of the internal iliac artery is approximately twice the size of the external iliac artery. The aorto-iliac segment observed proximally to distally reduces its cross-sectional area, thereby resulting in an increase in blood velocity.

An idiopathic congenital abdominal aortic aneurysm with impending rupture in a 23-month-old boy

Abdominal aortic aneurysms are distinctly uncommon in infants and children. These aneurysms, which are idiopathic in nature without any definite predisposing factors, are exceedingly rare. We present the case of a giant idiopathic congenital infrarenal abdominal aortic aneurysm with impending rupture in a 23-month-old boy, which was successfully treated with surgical repair using a cryopreserved cadaveric allograft. To the best of our knowledge, this is the oldest case and the third successful treatment of an idiopathic congenital abdominal aortic aneurysm repaired with a cryopreserved allograft in infants and children. Continued follow-up with multimodality imaging is required.

Extensive congenital abdominal aortic aneurysm and renovascular disease in the neonate

Primary congenital abdominal aortic aneurysm is an extremely rare entity, with only 15 patients reported in the literature. Options for repair are often limited secondary to branch vessel size and other anatomic limitations. We present a neonate diagnosed with an abdominal aortic aneurysm on prenatal ultrasound. A postpartum computed tomography angiogram revealed an extensive type IV thoracoabdominal aortic aneurysm extending to the aortic bifurcation and resulting in bilateral renal artery stenosis. The unique features of this patient and challenges in management are discussed.

Prenatal diagnosis of abdominal aortic aneurysm

We report a rare case of congenital abdominal aortic aneurysm diagnosed early prenatally.