Revealing the Rare: Prenatal Diagnosis of Inferior Vena Cava
Aneurysm
Miraç Özalp1, Murat İbrahim Toplu 2, Doğan Çağrı Tanrıverdi3, Türkay
Sarıtaş3
1 Associate professor, M.D., Prof.Dr.Cemil Taşcıoğlu City Hospital,
Department of Perinatology, İstanbul, Turkey, ozalpmirac@gmail.com
Orcid No: 0000-0002-2255-1642
2 M.D., Prof.Dr.Cemil Taşcıoğlu City Hospital, Department of Gynecology
and Obstetrics, İstanbul, Turkey, mitoplu@gmail.com
Orcid No: 0000-0003-1358-9099
3 M.D. Prof.Dr.Cemil Taşcıoğlu City Hospital, Department of Pediatric
Cardiology, İstanbul, Turkey, dctanriverdi@outlook.com
Orcid No:0000-0002-9871-1155
3 Professor, M.D., Prof.Dr.Cemil Taşcıoğlu City Hospital, Department of
Pediatric Cardiology, İstanbul, Turkey, turkaysaritas@yahoo.com
Orcid No: 0000-0003-0434-2545
Corresponding Author: Murat İbrahim Toplu
Prof.Dr.Cemil Taşcıoğlu City Hospital, Department of Gynecology and
Obstetrics,
İstanbul, Turkey
Telephone: +905317262517
e-mail: mitoplu@gmail.com
Abstract
This case report highlights the prenatal diagnosis of a rare saccular
inferior vena cava (IVC) aneurysm. A 25-year-old gravida 4 para 1
patient underwent detailed ultrasonography at 20 weeks of gestation,
revealing a 15 x 10 x 14 mm infrarenal IVC aneurysm. Genetic analysis
identified a de novo 2p16.3 deletion of uncertain significance. Serial
imaging showed progressive aneurysm dilation and mild cardiomegaly.
Postnatal CT angiography confirmed the aneurysm, and anticoagulant
therapy was initiated. This report underscores the importance of
detailed prenatal imaging and genetic evaluation in the identification
and management of rare vascular anomalies, contributing to the
understanding of their clinical implications.
Inferior vena cava (IVC) aneurysm, a scarce condition, presents with a
diverse range of anatomical and clinical manifestations1. Since its initial documentation by Oh et al. in
1973, 59 IVC aneurysms have been sporadically reported in the
literature, as comprehensively reviewed by Wu et al. in 20182,3. These cases, spanning an age range of 2 to 89
years, underscore the unusual nature of this condition. This report
discusses a unique case of IVC aneurysm identified in the prenatal
period.
A 25-year-old gravida 4 para 1 patient with a history of cesarean
section presented at 20 weeks of gestation for a detailed ultrasound
scan. No prenatal screening tests had been conducted, and no additional
features were noted in the patient’s medical history. Ultrasound
examination revealed a saccular IVC aneurysm measuring 15 x 10 x 14 mm,
extending from the right infrarenal region to the upper border of the
bladder (Figure 1) (Videoclip S1-S2). The portal veins, ductus venosus,
and hepatic veins appeared normal. Fetal echocardiography identified no
abnormalities except for an echogenic cardiac focus in the left
ventricle. After counseling, amniocentesis was performed at 23 weeks
based on the couple’s decision. Microarray analysis revealed a 35.7 kB
heterozygous deletion in the 2p16.3 region, classified as a variant of
uncertain significance (VUS). Literature indicates partially overlapping
pathogenic findings in this region 4,5. The clinical
exome panel detected no pathogenic variants or VUS. Analysis of the
parents’ peripheral blood samples showed no similar changes, and the
deletion was deemed de novo.
Routine assessments throughout pregnancy, including Doppler parameters,
TORCH serology, and oral glucose tolerance test results, were within
normal limits. At 33 weeks, the fetal IVC aneurysm measured 23 x 21 x 26
mm, and the heart-to-chest circumference ratio was 65%, suggesting
cardiomegaly (Figure S1). The foramen ovale flap extended distally to
the mitral valve by 8.5 mm, and a foramen ovale aneurysm was observed
(Figure S2). From this examination onward, the fetal abdominal
circumference remained consistently above the 97th percentile. At 35
weeks, the patient presented to the emergency department in active labor
and delivered a live female infant weighing 2830 g by cesarean section.
On the first postnatal day, computed tomography angiography confirmed a
15 mm saccular aneurysm in the IVC, while the thoracic and abdominal
aorta and branches appeared normal (Figure 2). The newborn was started
on anticoagulant therapy, and follow-up is ongoing. Written informed
consent was obtained from the family for publication.
IVC aneurysms, although rare, span a broad spectrum of clinical
presentations, ranging from asymptomatic incidental findings to
life-threatening conditions 6. To the best of current
knowledge, this case represents the first documented instance of an IVC
aneurysm diagnosed in the prenatal period. Thompson et al. proposed a
classification for IVC aneurysms based on etiology, categorizing them as
Type 1 congenital, Type 2 acquired, and Type 3 secondary to
arteriovenous fistula 7. Gradman et al. further
classified IVC aneurysms by anatomical and embryological characteristics
into four types: Type 1 includes aneurysms of the suprahepatic IVC
without venous obstruction; Type 2 involves aneurysms with interruptions
above or below the hepatic vein; Type 3 represents infrarenal IVC
aneurysms without venous obstruction; and Type 4 includes all other IVC
aneurysms 8. In this case, the IVC aneurysm was
infrarenal and congenital. Types 2-4 are associated with higher
complication rates, including aneurysm rupture, thrombosis in the deep
leg veins or the IVC, and pulmonary embolism 3,9.
Treatment options for IVC aneurysms include conservative management,
ligation, endovascular stent-graft, and end-to-end anastomosis; however,
due to the rarity of IVC aneurysms, no consensus has been reached
regarding treatment strategies 6,9. Decisions on
conservative or surgical management should consider thromboembolism
risk, associated conditions, clinical scenarios, surgical risks, and
patient preferences holistically.
None of the authors have any conflicts of interest to declare.