Skip to main content

Table 1 The advantages, disadvantages, and techniques of different modalities for evaluation of PLSVC

From: Persistent left superior vena cava: clinical importance and differential diagnoses

Imaging modality Pros Cons Techniques
Echocardiography Cheap
Widely available
No ionizing radiation
Not affected by cardiac rhythm
Portable (bedside assessment)
Real-time imaging
Enables evaluation of flow direction
Difficult to interpret
Operator-dependent
Acoustic window dependent
The spatial resolution could be limited.
* Coexistence of dilated coronary sinus without any evidence of right-sided congestion and positive “Bubble study” are diagnostic sonographic findings for PLSVC.
* “Bubble study” is conducted with the injection of agitated saline from the left peripheral arm veins. If PLSVC is present, the agitated saline bubbles firstly are seen in the coronary sinus, before the right atrium.
* In case of isolated PLSVC, positive “Bubble study” is observed after injection from right peripheral arm veins, as well.
* Contrast-enhanced echocardiography and transesophageal echocardiography are other useful modalities for the detection of PLSVC.
Multidetector computed tomography Accessible
Fast scanning speed
The best spatial resolution
Enables multiplanar imaging and reformatting
Radiation exposure (Recently developed dose reduction methods have partially reduced concerns about radiation exposure.)
An iodinated contrast agent (allergy, nephrotoxicity)
Cardiac rhythm changes may cause artifacts.
Need for sedation in the pediatric age group
* “ECG-gated CCTA with thin slices and multiplanar reformation” provides a detailed assessment.
* “Intravenous non-ionic iodinated contrast injection with a dose of 0,5-2 ml/kg at a rate of 1-2 ml/s” is recommended.
*The identification of PLSVC is usually independent of the contrast injection route (right or left, upper or lower extremities). The optimal contrast opacification of PLSVC is mostly seen in the delayed venous phase images.
Magnetic resonance imaging Radiation free
High spatial resolution
Enables multiplanar image acquisition
Enables assessment of flow direction
Depiction of PLSVC even without the administration of contrast media
Non-iodinated contrast
High cost
Less accessible
Slow scanning speed
Contraindications such as the magnetic implant, claustrophobia.
Cardiac rhythm changes may cause artifacts.
Need for sedation in the pediatric age group
* Axial and coronal cine SSFP sequences are the best sequences for imaging of PLSVC.
* The black blood TSE T2 images is also useful.
* Contrast-enhanced MRA
(± Dynamic imaging) and phase contrast angiography can be used as auxiliary modalities.
Invasive angiography Gold standard
Excellent morphologic information
Interventions can be made if necessary
Invasive
Radiation exposure
An iodinated contrast agent (Allergy, nephrotoxicity)
Need for sedation in the pediatric age group
* The catheter angiography with water-soluble contrast agent is performed. Venograms are obtained after bolus contrast injection from the catheter.
* Invasive angiography is not a routine imaging modality for evaluation PLSVC.
* PLSVC can be detected incidentally during procedures like central venous catheter insertion or pacemaker implantation.
  1. PLSVC persistent left superior vena cava, ECG-gated CCTA electrocardiogram-gated coronary computed tomography angiography, SSFP steady-state free precession, TSE turbo spin echo, MRA magnetic resonance angiography