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.