Introduction
Partial anomalous venous connection (PAPVC) is defined as the abnormal venous connection between one or more pulmonary veins (PVs) and the right atrium or its tributaries, such as the venae cavae, the innominate vein or the coronary sinus (1). It accounts for approximately 3% of all congenital heart diseases (2). Anomalous right-sided PV drainage is by far the most common form of PAPVC, representing at least 90% of the cases. In these patients, the right upper and middle PVs are the most frequently involved, and they usually drain into the right atrium at the level of its lateral free wall, into the superior vena cava (SVC) or at the cavo-atrial junction (3). Left-sided PAPVC is less frequent (10%), and it features the drainage of one or more left PVs, directly or by means of an additional vertical vein, into the innominate vein, the coronary sinus or a persistent left SVC (4).
In 90% of cases, right-sided PAPVC is associated with a sinus venosus type atrial septal defect (ASD), in most instances located near the superior cavo-atrial junction (5). An intact interatrial septum is observed in only 3% of patients with PAPVC.
Over the past decades, several surgical strategies for the correction of the PAPVC have been described. The “single-patch” technique is utilized when the right PVs drain into the cavo-atrial junction in close proximity to the ASD. In these cases, a single patch is indeed sufficient to perform both the ASD closure and the PVs rerouting to the left atrium (6). The “double-patch” technique is generally chosen instead when the PVs are connected to the SVC above the cavo-atrial junction. In these instances, after the ASD closure and the PVs rerouting, an additional pericardial patch is used to enlarge the cavo-atrial junction, thus preventing SVC stenosis (7). The Warden procedure, originally described in 1984 (8), is a useful technique that can be performed when the PVs connection lies above the superior cavo-atrial junction. The SVC is transected just above the most superior PV and the distal caval stump is used as a channel for rerouting the pulmonary venous return into the left atrium through the ASD. Finally, the proximal stump of the transected SVC is anastomosed to the right atrial appendage (9).
The “double-decker” procedure, albeit more challenging and less widely performed, certainly deserves to be mentioned as well. It encompasses the same surgical principles of the Warden procedure, to reroute the pulmonary blood flow and to avoid any surgical manipulation of the sinoatrial (SA) node, but without division and subsequent reconnection of the SVC (10).
The most common postoperative complications after PAPVC repair are SVC stenosis, PVs stenosis and atrial arrhythmias. The latter are mostly associated to surgical procedures that entail an extensive incision of the cavo-atrial junction, as in this instance the loss of sinus rhythm with transient or permanent junctional or atrial ectopic escape is frequently observed (11). The Warden procedure and the double-decker technique avoid surgical incisions near the SA node, presenting therefore a very low incidence of atrial rhythm disturbances (9;10). When SVC reconstruction is performed, as in the Warden procedure and in the double-patch technique, the incidence of SVC stenosis is higher (7;9).
We herein present a retrospective analysis of our experience in surgical management of PAPVC associated with sinus venosus type ASD. The aim of this study was to retrospectively compare early and long-term outcomes of pediatric and adult patients in relation to different surgical techniques utilized, focusing in particular on the occurrence of postoperative rhythm disturbances.