Posterior Tunnel Fontan and Senning-Type Pulmonary Venous Baffle
The patient was a 3-year, 1-month-old 12.2 kg girl with an antenatal diagnosis of complex congenital heart disease consisting of (S,L,L) dextroversion (atrial situs solitus with apex rightward) with a large inlet ventricular septal defect (with straddling tricuspid valve), severe right ventricular hypoplasia, and pulmonary atresia. On day of life six, the patient underwent a 3.5 mm central shunt (ascending aorta to right pulmonary artery) placement, main pulmonary artery transection, and patch reconstruction of left and right pulmonary arteries.
At four months of life, the patient underwent bidirectional Glenn, central shunt takedown, and patch augmentation of branch pulmonary arteries. At two years of life, the patient was getting progressively cyanotic and was taken to the catheterization lab and found to have normal hemodynamics, bilateral pulmonary venous desaturation, and microvascular arteriovenous malformations (AVMs). The extent was the patient’s AVMs were predominately right-sided without any targets for catheter-based intervention at that time. The patient did well postprocedurally, but her cyanosis progressed, and she began to become symptomatic manifesting with exertional shortness of breath with O2 saturations dropping to mid-50s during activity. Outside of cyanosis, the patient had done very well, was active, playful, and interactive.
The patient was presented at the Case Management Conference with the consensus being that the patient was a good Fontan candidate with acceptable hemodynamics, however the exact surgical strategy was unclear given the position of her complex anatomy and position of inferior vena cava.
Intraoperatively, the patient’s left pulmonary veins were more anterior than the left pulmonary artery. The right pulmonary artery was posteriorly-directed, rendering the lateral tunnel option not possible. An extracardiac conduit was also not ideal given the position of the inferior vena cava (midline). Placing an extracardiac conduit would have left the cardiac mass to rest directly on top of the conduit, likely causing obstruction. Creation of a posterior tunnel (created from Gore-Tex patch) appeared to be the best option. The inferior portion of the tunnel incorporated the inferior vena cava and atrial septum. The connection with the pulmonary artery was created by incising across the dome of the left atrium, across the atrial septum, and across the right atrium. The inferior portion of this incision was sutured to the inferior portion of the transverse incision from the left pulmonary artery to the right pulmonary artery (just below bidirectional Glenn anastomosis). The superior portion of the tunnel was sewn to the superior portion of pulmonary arteriotomy. The lateral aspect of the tunnel incorporated the atrial septum.
A bovine pericardial patch was then sewn to the left lateral atrial wall and along the original atriotomy incision. This Senning-type baffle directs blood from the left atrium over the top of the posterior tunnel and across the systemic atrioventricular valve.
The patient had an uncomplicated postoperative course and is doing well as an outpatient.