Abstract
Variations in venous circulation can affect either the superior or
inferior vena cava, with diagnoses often being incidental and presenting
with highly variable symptoms. This case discusses the detection and
investigation of bilateral superior vena cava agenesis in an
asymptomatic patient. Systemic venous anomalies affecting the superior
vena cava (SVC) are rare developmental disorders that occur during
embryological development. SVC anomalies are usually asymptomatic but
can complicate procedures such as cardiac catheterization, systemic
venous cannulation for extracorporeal membrane oxygenation, and
transvenous pacemaker implantation[1](#ref-0001). These anomalies
are typically diagnosed through echocardiography, computed tomography
(CT), magnetic resonance imaging (MRI), or during failed cardiac or
venous catheterization due to IVC course anomalies[2](#ref-0002).
They are more common in males and may be associated with congenital
heart diseases, rhythm disturbances, or both[3](#ref-0003). The
most common SVC anomalies include the presence of bilateral SVC and the
absence of the right SVC with persistent left SVC[4](#ref-0004).
Bilateral SVC absence is extremely rare.