Introduction
Total anomalous pulmonary venous return is a rare CHD, comprising about 1% of all CHDs. In total anomalous pulmonary venous return, the pulmonary veins fail to establish a direct connection with the left atrium, instead draining anomalously into the right atrium, coronary sinus, or systemic veins. This results in a mix of oxygenated and deoxygenated blood entering the systemic circulation, leading to cyanosis and potentially heart failure. Total anomalous pulmonary venous return is categorised into four types based on the site of anomalous drainage: supracardiac, cardiac, infracardiac, and mixed types, with supracardiac being the most common.
The severity of clinical symptoms is largely dependent on whether the pulmonary venous return is obstructed or non-obstructed and on the presence of communication between the right and left hearts. Obstruction is associated with more severe clinical manifestations, such as early-onset cyanosis, respiratory distress, and acidosis, often necessitating emergent surgical intervention in the neonatal period. In contrast, non-obstructive cases can present with milder symptoms and are usually managed with elective surgery during infancy.
In this article, we present a case of a neonate with non-obstructive supracardiac total anomalous pulmonary venous return who underwent a two-stage hybrid repair, combining surgical and percutaneous approaches.
Case description
A one-week-old newborn male was admitted in the neonatal ICU due to hypoxaemia, with oxygen saturation levels around 90%, which did not improve with supplemental oxygen. Upon admission, he appeared mildly cyanotic but was haemodynamically stable, with no significant respiratory distress or acidosis. Physical examination revealed mild post-prandial prostration, a grade II/VI systolic murmur detected during cardiac auscultation but no other alarming clinical findings were present.
A transthoracic echocardiogram was performed, revealing an abnormal pulmonary venous return, suggestive of total anomalous pulmonary venous return and an atrial septal defect with right to left shunt. These findings were confirmed by a contrast-enhanced chest CT angiography, which showed non-obstructive supracardiac total anomalous pulmonary venous return. The imaging demonstrated that the left pulmonary veins drained via a common conduit into a right vertical vein, and the right pulmonary veins drained independently into the same vertical vein. The vertical vein then drained into the azygos vein, which connected to the superior caval vein approximately 4 mm from its junction (Figures 1 and 2).
Chest Angio CT confirming the diagnosis of TAPVR, with the presence of a common venous conduct (red) draining to a right vertical vein (yellow) that communicates with in the azygos vein (green) and consequent SVC.
Schematic representation of the patient’s TAPVR. ASD - atrial septal defect; IVC - inferior vena cava; LA - left atrium; LV - left ventricle; RA - right atrium; RV - right ventricle, SVC - superior vena cava.
Despite an initial period of clinical stability, over the following weeks the infant began to exhibit signs of worsening heart failure, including tachypnoea, poor feeding, and inadequate weight gain, despite appropriate medical management, including diuretics and angiotensin-converting enzyme inhibitors. These symptoms suggested increased pulmonary blood flow. Transthoracic echocardiogram showed smaller left heart chambers, with left ventricle dysfunction not only due to the right-to-left motion of the interventricular septum but also to the inherently lower preload of the left ventricle.
The progressive heart failure indicated the need for surgical intervention. However, surgery had to be postponed due to a neonatal sepsis and necrotising enterocolitis that were successfully treated.
Surgical intervention
At 1.5 months of age and weight of 3805 g, the patient underwent heart surgery. The surgical approach included the closure of a large atrial septal defect and anastomosis of the anomalous pulmonary venous conduit to the left auricle. However, during the procedure, it was not possible to ligate the vertical vein, which was responsible for the anomalous drainage into the superior caval vein. Attempts to wean off bypass were made on two occasions following ligation of the vertical vein, both of which were unsuccessful due to a significant increase in left atrial pressure (28 mmHg) and low systemic output, which posed a risk of postoperative pulmonary venous congestion. Intraoperatively, a non-haemodynamically significant gradient (3–4 mmHg) was observed in the confluence. The surgical team opted to leave the vertical vein patent and close the sternum, believing that the left ventricle would gradually recover diastolic function in the postoperative period and that the shunt through the vertical vein would not be haemodynamically significant. Pre and post cardiopulmonary bypass systolic pulmonary artery pressures were 60 mmHg and 40 mmHg, respectively, aortic pressures remained stable.
Postoperatively, the patient continued to experience congestive heart failure, with signs of pulmonary overflow, including pulmonary oedema and persistent tachypnoea. Repeat echocardiography confirmed significant residual flow from the vertical vein into the superior caval vein, necessitating further intervention.
Cardiac catheterisation
Given the observed failure of the left ventricle to adapt to post-operative conditions and the persistence of heart failure symptoms, the case was revisited in a multidisciplinary meeting. It was decided to proceed with a haemodynamic evaluation. Cardiac catheterisation confirmed the presence of a partially corrected total anomalous pulmonary venous return, with the vertical vein still draining into the azygos vein and then into the superior caval vein.
During the procedure, a balloon occlusion test using a Tyshak balloon was performed to temporarily obstruct the azygos vein and assess the haemodynamic response. Although there was a slight rise in the left auricle pressure, the patient remained haemodynamically stable. This encouraged the interventional team to proceed with percutaneous closure of the anomalous connection.
Using a right femoral venous approach, it was deployed a 6-mm Amplatzer Vascular Plug (Abbott Cardiovascular®) device to occlude the azygos vein and interrupt the anomalous pulmonary venous drainage to the superior caval vein. Post-occlusion angiography confirmed the correct positioning of the device, with no residual shunt and adequate patency of the superior caval vein and the vertical vein. The patient tolerated the procedure well, with no major complications observed.
Post-intervention outcome
Following the percutaneous intervention, the patient demonstrated significant clinical improvement. Over the subsequent weeks, his heart failure symptoms gradually resolved, and his weight gain normalised. A follow-up chest CT angiography performed four months after the procedure confirmed the stable position of the Amplatzer device, with complete occlusion of the azygos vein, patency of all four pulmonary veins, and normal flow through the superior caval vein. There were no signs of pulmonary venous obstruction or residual shunting (Figure 3).
Chest angio-CT post-surgery and percutaneous device implantation (pink); vertical vein (yellow), azygos vein (green).
At the most recent follow-up, the patient remained asymptomatic, with no evidence of recurrent heart failure or pulmonary hypertension.
Discussion
The standard approach for treating total anomalous pulmonary venous return is early corrective surgery, particularly in cases with obstructed venous return or severe heart failure. Pulmonary venous obstruction and unfavourable anatomy, Reference Mulia and Rahman1 such as found in our patient, have been identified as preoperative risk factors. In this case, the preoperative dysfunction and smaller size of the left ventricle likely contributed to its poor immediate adaptation following the connection of the pulmonary veins to the left atrium. The less compliant left ventricle, unable to suddenly accommodate the full pulmonary venous return, required an “escape” through the vertical vein, as the atrial septal defect had already been closed.
In obstructive type, total anomalous pulmonary venous return with a restrictive foramen ovale, a percutaneous balloon atrial septostomy is necessary in the first hours of life or a percutaneous stent placement in the obstruction site may be also required. In non-obstructive types, some reports suggest percutaneous intervention as an option to delay surgical treatment in newborns or unstable patients. Kisamori et al Reference Kisamori, Kotani and Raja2 compared stenting of the obstructive conduit versus surgical correction, in a group of newborn patients with right atrial isomerism, a functional single ventricle and anomalous pulmonary venous connection, and found that the group that had primary percutaneous stenting showed improved survival.
Currently, most partial anomalous venous pulmonary returns are treated surgically. Reference Shen3 However, there are very few partial anomalous pulmonary venous return (PAVPR) cases described in the literature that have been repaired percutaneously through device implantation. Little is known regarding long-term complications of device implantation in these cases and the need and duration for antiplatelet therapy. Reference Mamas, Clarke and Mahadevan4–Reference Saedi and Saedi8
To the best of our knowledge, there are no reported cases of a two-stage “hybrid” approach for non-obstructive total anomalous pulmonary venous return.
Conclusion
With this case, the authors aim to demonstrate that anatomical variants and haemodynamic changes in total anomalous pulmonary venous return do not always permit complete correction in a single surgical procedure. In such cases, a hybrid approach, combining surgical repair and percutaneous intervention, can offer an effective alternative. The case highlights the importance of individualised management strategies in the treatment of complex CHDs like total anomalous pulmonary venous return.
Acknowledgements
None.
Financial support
This research received no specific grant from any funding agency, commercial, or not-for-profit sectors.
Competing interests
None.
