Case In Point: Persistent left superior vena cava in an elderly man with pneumonia

October 1, 2006

The authors report the incidental finding of a persistent left superior vena cava (PLSVC) during the routine placement of a left subclavian central line in an elderly man with acute renal failure.

The case

An 84-year-old man was admitted to the ICU with acute renal failure, pneumonia, and sepsis. He did not have a significant personal or family history of cardiovascular disease.

A central venous catheter was placed through the left subclavian vein without complication. Central venous pressure was 5 mm Hg. A postprocedural frontal chest radiograph revealed the catheter lying at the left side of the aorta, which raised the suspicion of a congenital vascular anomaly (Figure 1).

Transthoracic Doppler echocardiography confirmed the diagnosis of PLSVC. The echocardiogram showed the dilated coronary sinus as an echo-free space posteriorly between the left atrium and the ventricle (Figure 2). Saline contrast injected into the left antecubital vein drained through the PLSVC into the enlarged coronary sinus and then into the right atrium.

The Doppler color flow study revealed mild to moderate tricuspid regurgitation. The estimated systolic pulmonary pressure was 32 mm Hg, and the estimated ejection fraction was 60% without evidence of wall motion abnormalities. There was no evidence of diastolic dysfunction, and findings from the remainder of the study were normal. CT of the chest was done to evaluate the anomaly and the lung parenchyma (Figure 3).

Despite the free flow of venous blood from all catheter ports, the line was removed. The patient clinically improved with fluids and antibiotics, and he was discharged.

Discussion

PLSVC is an uncommon congenital defect that is the most common anomaly of thoracic venous return. It is found in about 0.3% of the general population and in 3% to 10% of patients with congenital heart disease.1 It is most commonly discovered after central venous or pulmonary artery catheter placement. PLSVC is associated with the presence of the right superior vena cava in 82% of cases.2

In the normal early embryonic stage, the anterior cardinal veins draining the head, neck, and arms join with the posterior cardinal vein and enter the heart as the right and left horns of the sinus venosus. Both the right and the left cardinal veins drain into the right atrium at this stage. Most of the left-sided cardinal system disappears, leaving only the coronary sinus and a remnant known as the ligament of Marshall.

Simple failure of obliteration of the left anterior cardinal vein results in PLSVC. In most cases, PLSVC drains into the right atrium via the coronary sinus. However, if developmental arrest occurs at an earlier stage, the coronary sinus is absent and the PLSVC drains directly into the right atrium.

An accurate diagnosis of PLSVC is possible when a contrast-enhanced CT scan demonstrates that PLSVC is draining into the coronary sinus. The diagnosis can also be based on findings of transthoracic Doppler echocardiography, as was the case with our patient.3 Venography with simultaneous chest radiography is another noninvasive bedside test that can be helpful for confirming the diagnosis.4 Other reported diagnostic modalities are angiography and MRI.5,6

This isolated anomaly does not require specific treatment. However, it is important that internists and intensivists be able to recognize PLSVC because of its association with other cardiovascular malformations and because of the difficulties that this anomaly can cause during central venous catheterization, pacemaker electrode placement, and cardiopulmonary bypass surgery.7,8 Such anomalies include tetralogy of Fallot, Eisenmenger syndrome, coarctation of aorta, atrial septal defect, ventricular septal defect, and endocardial cushion defect. Some of these accompanying lesions can increase the risk of paradoxical embolism.8

References:

REFERENCES


1. Buirski G, Jordan SC, Joffe HS, Wilde P. Superior vena caval abnormalities: their occurrence rate, associated cardiac abnormalities and angiographic classification in a paediatric population with congenital heart disease.

Clin Radiol.

1986;37:131138.
2. Winter FS. Persistent left superior vena cava; survey of world literature and report of thirty additional cases.

Angiology.

1954;5:90- 132.
3. Alhaj EK, Pizzarello RA, Bergmann SR, et al. A case report of absent right superior vena cava with persistent left superior vena cava: echocardiographic findings.

J Am Soc Echocardiogr.

2005;18:483-485.
4. Ghadiali N, Teo LM, Sheah K. Bedside confirmation of a persistent left superior vena cava based on aberrantly positioned central venous catheter on chest radiograph.

Br J Anaesth.

2006;96:53-56.
5. Kaemmerer H, Prokop M, Schirg E, et al. Unilateral left superior vena cava in absent right superior vena cava. Modern imaging diagnosis and clinical relevance [in German].

Z Kardiol.

1994;83:386-391.
6. Koito H, Suzuki J, Ohkubo N, et al. Three-dimensional reconstructed magnetic resonance imaging for diagnosing persistent left superior vena cava: comparison with magnetic resonance angiography and plain chest radiography.

J Cardiol.

1996;28:161-170.
7. Lenox CC, Zuberbuhler JR, Park SC, et al. Absent right superior vena cava with persistent left superior vena cava: implications and management.

Am J Cardiol.

1980;45: 117-122.
8. Wood PH.

Diseases of the Heart and Circulation.

2nd ed. London: Eyre & Spottiswoode; 1956.