Keywords
congenital abnormality - tunneled central catheter - persistent left superior vena
cava
Introduction
Tunneled dialysis catheters are used as vascular access for hemodialysis (HD) in end-stage
renal disease (ESRD) patients. The right internal jugular vein (IJV) is favored for
catheter insertion because of the comparative straighter course to the superior vena
cava (SVC) and right atrium (RA) with lower incidence of central vein stenosis. The
left IJV is preferred only when the right IJV is afflicted with an obstructive pathology.[1]
Knowledge of the variant anatomy of central vessels is paramount so as to look out
for any complications and increasing safety. A common variant is a persistent left
superior vena cava (PLSVC). It has been observed in 0.5 to 2% of the common community
with its incidence rising up to 10% in people suffering from inherent anomalies of
the heart.[2] Isolated PLSVC with absent right SVC occurs in 0.09 to 0.13% of patients.[3]
[4] PLSVC commonly drains into the RA via the coronary sinus in as many as 80 to 90%
of individuals with no significant sequalae.[4]
We present a case of PLSVC draining directly into IVC with an incidentally detected
rare drainage pathway during the placement of a left IJV tunneled HD catheter.
Case Report
A 27-year-old male with ESRD who was on maintenance HD for the last 3 months was admitted
to our hospital with complaints of fever and chills and with serum creatinine 10.75 mg/dL.
He was being dialyzed through HD catheter through left IJV. In view of suspicion of
catheter related blood stream infection, left Juglar HD catheter removal with insertion
of tunneled central catheter was planned. Computed tomography angiogram thorax showed
left-sided SVC with common channel into IVC, draining separately from coronary sinus
([Fig. 1A–F]). Note was made of common origin of right brachiocephalic artery and left common
carotid artery, which is a common aortic arch variant ([Fig. 1B]). No other anatomic variants were found on the computed tomography (CT). Echocardiography
did not show any dilated coronary sinus that may be found in cases of PLSVC.
Fig. 1 A 27-year-old male with end-stage renal disease planned for left internal jugular
vein tunneled hemodialysis catheter. (A, B) Computed tomography angiogram thorax (venous phase) axial with reformatted coronal
image shows contrast opacified persistent left superior vena cava (red arrow) with
no right superior vena cava and patent left innominate vein. (C–F) Further sections of computed tomography in serial axial and coronal reformatted
images show contrast opacified persistent left superior vena cava joining into the
suprahepatic inferior vena cava (white arrow) through a common channel (yellow arrow)
that is draining separately and posterior to coronary sinus (light blue chevron).
(A) Common origin of right brachiocephalic artery and left common carotid artery is
seen (light blue arrow).Note is also made of bilateral pleural effusion.
Under all aseptic precautions, left IJV was punctured using single wall needle under
ultrasound guidance and the guide wire was passed. The dialysis catheter was tunneled
from his left anterior upper chest wall. The guidewire was removed after passing a
peel away introducer over it. The introducer showed frank venous blood exiting from
it. The introducer was simultaneously peeled off as the tunneled HD catheter was passed
through it. Both lumens of tunneled HD catheter showed frank venous blood on aspiration.
On confirming position on fluoroscopy, digital subtraction venogram confirmed that
the catheter courses through left SVC ([Fig. 2A]) with the contrast directly exiting to IVC then drained via a common channel into
RA ([Fig. 2B–F]) There was no contrast filling of coronary sinus or right SVC. The tip of catheter
was placed at junction of left-sided SVC and IVC just distal to junction of common
channel and RA under fluoroscopic guidance.
Fig. 2 A 27-year-old male with end-stage renal disease planned for left internal jugular
vein (IJV) tunneled hemodialysis (HD) catheter. (A) Intraprocedural fluoroscopic image
of thorax shows the tunneled HD catheter (red arrow) coursing through the left IJV
and persistent left superior vena cava (SVC) with its tip just distal to the common
channel. Note made of small left IJV hemodialysis catheter (red chevron). (B–D) Digital subtraction angiographic images showing the contrast flow (red arrows) from
the HD catheter (B, C) and tunneled HD catheter (D–F) lying in persistent left SVC into the inferior vena cava (white arrow) and then
flowing into the right atrium (white chevron) via a common channel (yellow arrow).
Supplementary Material Video 1 CECT scan showing left SVC draining via common channel with IVC.
Check aspirations and saline injection showed free flow in both the lumen that were
flushed and closed with heparin lock.
No procedural complications were encountered. The catheter was effectively used for
HD treatments. The temporary HD catheter was then subsequently removed.
Discussion
The tunneled HD catheter offers advantages like immediate use after placement with
no repeated venepuncture with a cost of higher chances of infection and cardiovascular
events.
Left SVC is the most common congenital abnormality of thoracic venous system. Embryologically,
the superior and inferior cardinal veins (CV) drain the cranial and caudal parts of
fetus after forming the right and left common CV to drain into heart. The cephalic
part of SCV forms the IJV, whereas the caudal portion of right SCV forms the SVC,
and the caudal portion of left SCV regresses and forms “ligament of Marshall.” The
innominate veins are formed via the anastomosis between right and left SCVs. When
the caudal portion of left SCV fails to regress, it forms PLSVC. Most commonly bilateral
SVC are present with degeneration of innominate vein in some cases, while the PLSVC
drains into coronary sinus.[5]
It can show association with other anomalies like atrial septal defect, coarctation
of aorta, bicuspid aortic valve, and ostial atresia of coronary sinus.[5] These anomalies can be looked out for with echocardiography or cardiac CT/MRI and
must be managed accordingly to the degree of symptomatology.
Normally, PLSVC can be used for tunneled HD catheter when right atrial drainage is
assured by echocardiography and CT affirms the patency of a patent left brachiocephalic
vein.[1] Under fluoroscopy guidance, the catheter is kept in PLSVC, draining to the RA with
catheter tip lying above the coronary sinus.[1] In this case, left SVC was not seen to be draining into the coronary sinus. On the
contrary, it was seen draining into the IVC that was then draining via a common channel
into the RA. The tip of catheter needs to be kept at such a position so that adequate
high flow is available for dialysis. Normally the tip of catheter is kept in RA for
adequate high flow; in this scenario it was kept at junction of SVC and IVC in the
common channel, just above the diaphragm, so that there was adequate blood flow for
HD without compromising vital structures.
In our knowledge, no such case has been reported where the left SVC is draining directly
into the IVC with common channel draining into the RA.
The left SVC probably causes difficulties in insertion of the catheter into the right
heart but does not prohibit the insertion. In studies, during the placement of HD
catheters, PLSVC is detected incidentally causing complications such as vascular thrombosis,
supraventricular arrhythmia, cardiac arrest, and vascular erosion that need to be
looked out for.[5]
In less than 10% of total cases with PLSVC, the PLSVC can be seen draining into left
atrium resulting in a small right to left shunt. Venous procedures should be avoided
in such cases due to higher risk of cyanosis, intracerebral abscess, embolic and paradoxical
stroke. In cases of larger shunting/hypoxemia, surgical correction is indicated.[6]
Conclusion
We reported a rare case of PLSVC draining directly into the IVC and then via a common
channel into the RA during left IJV tunneled HD catheter insertion.
One should always place tunneled HD catheter under fluoroscopy guidance and after
assessing preprocedure CT angiogram of thorax. An unusual track of guidewire is an
indication for performing venogram before placing the catheter blindly. Interventionists
should have familiarity with the anatomical variation imaging and complications.
