Modified Biatrial Approach for Obstructed TAPVC
In this video, the technique of a modified biatrial approach for a 7-month-old, 3.6 kg boy who presented with an obstructed TAPVC to the coronary sinus is shown. Median sternotomy was done, and the aorta and RA appendage were cannulated. During cooling, the ligamentum was divided and the LPA was looped so that the left upper pulmonary vein was freed first. The innominate vein and IVC were cannulated. The advantages of cannulating the innominate vein include: 1) it avoids SVC division and facilitates dissection by looping the SVC away, and 2) it helps in the easy approximation of the horizontal RA incision without any tension.
In this technique, the combination of superior and lateral approaches is used to dissect all four pulmonary veins, the confluence, and the vertical vein. The superior approach was facilitated by looping the RPA towards the head end and the SVC towards right, and the aorta was retracted towards the assistant’s side to dissect the left upper and lower pulmonary veins. During dissection, the core was cooled to 18 degrees for a short TCA in order to facilitate the disconnection of the vertical vein from the coronary sinus and the beginning of the venoatrial anastomosis in a bloodless clear field.
By using the lateral approach between the vena cavae and the right pulmonary veins, the confluence and the coronary sinus were easily dissected. After aortic cross clamp, on total bypass the RA was opened from the base of the appendage towards the interatrial septum and a short TCA was employed. The confluence was opened with its connection with the coronary sinus, and the coronary sinus was sutured in a double layer. The posterior limbus was marked temporarily with metal clips. While opening the LA posterior wall, the coronary sinus suture line was identified to stay away from it. The incision into the LA started at the middle of the posterior limbus and directed towards the tip of the LA appendage. This avoids any injury to the conduction system. The confluence was opened widely.
During the entire anastomosis between the LA and the confluence, the anteroposterior position of both the structures was maintained, which ensures an anastomosis without any distortion. Anastomosis was done with a 7-0 prolene running suture with locking every fourth bite to prevent a purse string effect. During the anastomosis, visualize the mitral valve and try to make an anastomosis larger than the mitral valve to accommodate for a possible postoperative narrowing due to fibrosis. A large anastomosis is ensured by: 1) fishmouthing the confluence and superior lip of the LA wall as needed and 2) the metal clip markers will give an idea of the septum where the anastomosis usually ends. In case the LA is small, the anastomosis can be extended beyond the septum onto the RA wall, which will be facilitated by the well mobilized pulmonary veins without any kinking.
Halfway through the anastomosis, circulation was started and rewarming was done so that by the end of the procedure, the authors were ready to come off pump. The ASD was closed with a larger patch, keeping the patch more towards the RA. It is always perforated in the middle with a clean incision, which acts like a pop off helping both the right and left ventricle in the postoperative period. Both a large ASD patch and the perforation helps to keep a low LA pressure, which helps in early recovery in the ICU. Most of the perforations were seen to be closed off in the postoperative follow-up, as there is no tissue loss. The right atrial incision was sutured without any tension. Aortic cross clamp was removed and slowly came off bypass. The sternum was stented open to be closed the next day.