Anomalous venous returns

It is not uncommon to find a persistent left superior vena cava (LSVC) on perioperative TEE examination. This occurs in 0.3-1% of the population and in 5% of congenital heart disease cases [2]. It generally drains into the coronary sinus, which is significantly enlarged (Figure 15.8) (Video).

Video: Dilatation of the coronary sinus in a case of left superior vena cava; the coronary sinus appears as a vertical tube near the top of the screen, draining into the right atrium; the right ventricle is hypertrophied.

The right superior vena cava (RSVC) may be present, hypoplastic or absent. Although LSVC is of no interest as a pathology, it entails risks for surgery or central venous canulation [2].



Figure 15.8: Left superior vena cava (LSVC). A: dilation of the coronary sinus (CS) (≥ 1.5 cm); injection of microbubbles into a vein in the left upper limb – these appear in the coronary sinus before reaching the RA.  B: short-axis view of the LSVC which appears between the left superior pulmonary vein (LSPV) and the left atrial appendage (LAA). 

• Thromboembolic risk linked to a left central venous catheter, which may prompt thrombosis of the coronary sinus – any catheter placed in the jugular or subclavian vein must be removed as soon as possible. Swan-Ganz catheters are contraindicated. If the RSVC is hypoplastic, a right-sided catheter may be virtually occlusive. If the RSVC is absent, a right jugular or subcalvian canulation can perforate the dead end. The problem is identical for endovenous pace-maker.
• Problem in terms of venous cannulation during CPB – the LSVC must be drained or excluded if the RSVC is of an appropriate gauge.
• In the event of retrograde cardioplegia, the infusate leaks into the SVC and does not perfuse the heart.
• Frequent associated AV blocks. 
• In the event of drainage into the LA (coronary sinus-type ASD).
• In the event of intravenous pacing.

The fortuitous discovery of an enlarged coronary sinus at preoperative echocardiography is suspicious of LSVC; it requests a CT-scan to confirm the diagnosis and to precise the presence or absence of a RSVC [2]. A pulmonary vein may take an anomalous course to the RA instead of anastomosing normally with the LA. This usually concerns a right superior pulmonary vein which connects with the root of the SVC into the RA (Figure 15.9). This anomaly results in right-sided overload (L-to-R shunt) with dilation of the SVC or IVC (depending on the connection), RA, and RV. It is often associated with a sinus venosus-type ASD. 



Figure 15.9: Partial anomalous pulmonary venous return. The right superior pulmonary vein (RSPV) flows into the superior vena cava (SVC) just above its anastomosis into the RA. RPA: right pulmonary artery (short-axis view of the ascending aorta at 0° with clockwise rotation of the probe).

Total anomalous pulmonary venous return constitutes a neonatal emergency (see Figure 14.33). It is not observed in adults since it is either operated on in childhood or results in death at an early age.



Figure 14.33: Diagram showing total anomalous pulmonary venous return. A: supracardiac type, into the innominate vein (IV) via a vertical vein (VV). B: cardiac type, via the coronary sinus (CS). C: infracardiac type, transdiaphragmatic into the portal vein (PV) via a descending vein (DV). D: mixed type. In the first three cases, a posterior collector (PC) drains venous blood from both lungs into a system located behind the atria.

Treatment involves reimplanting the anomalous pulmonary vein in the LA. Surgical correction of anomalous pulmonary venous return combined with a sinus venosus-type ASD involves creating a patch inside the anastomosis of the SVC into the RA so that the arterialised blood is diverted to the LA through the ASD (Warden procedure) [1]. Postoperatively, the flow should exhibit the systolic and diastolic biphasic morphology of central venous flows on an echocardiogram. The maximum velocity should remain below 1.0-1.5 m/s. A continuous non-oscillating flow with Vmax > 1.5 m/s indicates prohibitive restriction and requires surgical revision [4]. 


 

Anomalous venous returns

Left superior vena cava – drains into the widened coronary sinus. Risks: thrombosis of the coronary sinus due to a central catheter, leakage of retrograde cardioplegia into the SVC. Anomalous pulmonary venous return: in adults, only affects one pulmonary vein connected to the RA – equivalent to a L-to-R shunt.

© BETTEX D, CHASSOT PG, January 2008, last update February 2020

 

 

1. AGGARWAL N, GADHINGLAJKAR S, SREEDHAR R, et al. Warden repair for superior sinus venosus atrial septal defect and anomalous pulmonary venous drainage in children: anesthesia and transesophageal echocardiography perspectives. Ann Card Anaesth 2016; 19:293-9  
2. SHOIAB I, SCHAFF H, SARAN N, et al. Recommendations for perioperative management in patients with absent right superior vena cava. J Cardiothorac Vasc Anesth 2019; 33:1710-3  
3. STÜMPER O, SUTHERLAND GR. Transesophageal echocardiography in congenital heart disease. London: Edward Arnold, 1994, 37-38
4. VICK GW: Pulmonary venous and systemic ventricular inflow obstruction in patients with congenital heart disease: Detection by combined two-dimensional and Doppler echocardiography. J Am Coll Cardiol 1987; 9:580-4,