Simultaneous Transcatheter Closure of Coexistent Superior Sinus Venosus Defects and Oval Fossa Defects

Transcatheter Correction of Superior Venacaval Form of Sinus Venosus Defects Using Balloon-Mounted Covered STENTS

Superior sinus venosus defects (SVD) are interatrial communications located above the confines of the oval fossa, where unroofing of the right upper pulmonary vein leads to its anomalous drainage to the superior venacava. Recent emergence of transcatheter closure of these defects using covered stents is an attractive alternative option especially in adults with additional comorbidities. This article focuses on various aspects of non-surgical closure of SVD, including patient selection, appropriate hardware options, step-by-step procedural details, evolution and modifications in the techniques over the last decade, protocols for follow-up evaluation, and potential complications associated with this intervention.

Outcomes Following Surgical Repair of Sinus Venosus Atrial Septal Defects: A Systematic Review and Meta-Analysis

BACKGROUND

Sinus venosus atrial septal defect (SVASD) is a rare congenital cardiac anomaly comprising 5% to 10% of all atrial septal defects. Although surgical closure is the standard treatment for SVASD, data on outcomes have been confined to small cohorts. Thus, we conducted a systematic review of the outcomes of SVASD repair.

METHODS AND RESULTS

The primary outcome was death. Secondary outcomes encompassed atrial fibrillation, sinus node dysfunction, pacemaker insertion, cerebrovascular accident, reoperation, residual septal defect, superior vena cava obstruction, and reimplanted pulmonary vein obstruction. Pooled incidences of outcomes were calculated using a random-effects model. Forty studies involving 1320 patients who underwent SVASD repair were included. The majority were male patients (55.4%), with 88.0% presenting with associated anomalous pulmonary venous connection. The weighted mean age was 18.6±12.5 years, and the overall weighted mean follow-up period was 8.6±10.4 years. The in-hospital mortality rate was 0.24%, with a 30-day mortality rate of 0.5% reported in 780 patients. Incidences of atrial fibrillation, sinus node dysfunction, pacemaker insertion, and cerebrovascular accident over the long-term follow-up were 3.3% (2.18%-4.93%), 6.5% (5.09%-8.2%), 2.23% (1.34%-3.57%), and 2.03% (0.89%-2.46%) respectively. Reoperation occurred in 1.36% (0.68%-2.42%) of surgeries, residual septal defect in 1.34% (0.69%-2.42%), superior vena cava obstruction in 1.76% (1.02%-2.9%), and reimplanted pulmonary vein obstruction in 1.4% (0.7%-2.49%).

CONCLUSIONS

This is the first comprehensive analysis of outcomes following surgical repair of SVASD. The findings affirm the safety and effectiveness of surgery, establishing a reference point for evaluating emerging transcatheter therapies. Safety and efficacy profiles comparable to surgical repair are essential for widespread adoption of transcatheter treatments.

Transcatheter Covered Stent Exclusion of Superior Sinus Venosus Defects

BACKGROUND

Transcatheter correction of sinus venosus defects (SVDs) using balloon-mounted covered stents provides an attractive surgical alternative. Surgery may be complicated by superior vena caval or right upper pulmonary vein (RUPV) stenosis, sinus nodal dysfunction, and residual additional pulmonary veins.

OBJECTIVES

Being a new intervention, technical modifications would simplify the procedure, improve universal applicability, and reduce or tackle complications.

METHODS

Patients were included if balloon interrogation of cavoatrial junction confirmed closure of SVD and redirected RUPV to the left atrium. A single-center experience was analyzed to summarize the procedural modifications over 8 years. Transesophageal echocardiogram (TEE) on follow-up was done to identify residual shunt, RUPV flows, and stent thrombosis.

RESULTS

A total of 100 patients including 9 children with a median age of 35 years (range, 4-69 years) underwent SVD closure after balloon interrogation. Among 57 patients balloon interrogated in the first 5 years, 70% underwent transcatheter closure, with 2 failures. RUPV occlusion caused the exclusions. Inclusions improved to 94% among the subsequent 65 balloon interrogations when RUPV protection was implemented, with 1 failure. Stent embolization caused the 3 failures warranting surgery. Recent modifications included limited transesophageal echocardiogram without anesthesia, avoiding venovenous circuit, interrogation with semicompliant balloons, trans-septal RUPV protection, overlapping stents to permit additional vein drainage to superior vena cava and tackle embolizations. There were no deaths. Minor complications included stent embolizations stabilized in catheterization laboratory in 2 patients, left innominate vein jailing in 2 patients, insignificant residual flows, and nonocclusive asymptomatic stent thrombosis in 4 patients.

CONCLUSIONS

Procedural success was 97%. Recent modifications increased patient inclusions, decreased complications, and simplified the intervention.

Endoleak in covered CP stent causes procedural failure during transcatheter closure of sinus venosus defects

Transcatheter sinus venosus defect closure uses a long covered stent of appropriate length and diameter across the cavoatrial junction after balloon interrogation. The fabric in the covered stent creates a roof for the right upper pulmonary vein that closes the interatrial communication and redirects the vein into the left atrium behind the stent. A fabric tear in the covered stent may cause endoleak that will result in residual flows across the struts of the covered stent, causing procedural failure. This report highlights the identification of fabric leak by angiography and transesophageal echocardiography and steps to overcome this complication by the placement of another overlapping covered stent.

Different mechanisms for persistent and residual left-to-right shunt after transcatheter sinus venosus defect closure and their management

Transcatheter closure of superior vena cava (SVC) form of sinus venosus defects (SVDs) using covered stents is emerging as an alternative to surgery in the current decade. A covered stent placed in the cavoatrial junction creates a roof for the right upper pulmonary vein (RUPV) that stops the left-to-right shunt and redirects the vein to the left atrium. While surgical literature has clearly documented the incidence of stenosis of SVC and RUPV, sinus nodal dysfunction, and persistent residual shunts following surgical correction, it is imperative to have similar data after this new transcatheter intervention on the incidence of complications and follow-up outcomes. Since patients with pretricuspid shunts are often clinically asymptomatic, correction is primarily performed to prevent a persistent right heart volume overload and allow remodeling of the heart chambers. Any residual left-to-right shunt after a correction will result in persistent right heart dilatation. Residual flows can result from various mechanisms, including lack of apposition of the covered stent to the free edge of the SVD, fabric breach, and persistent anomalous drainage of additional right-sided pulmonary veins that drain very high in the SVC or can be due to a coexistent defect in the oval fossa. This review analyzes the different mechanisms, explains the transesophageal and angiographic images for each one, and offers solutions tailored for various reasons. Different mechanisms warrant different treatment principles. A solution for residual shunt from one mechanism may not be appropriate for residual flow through another mechanism. A thorough understanding would aid the operator in effective interventions for these SVDs.

Innominate vein occlusion by the fabric of covered stent during transcatheter closure of sinus venosus defects - Causes, management, and outcome

Transcatheter sinus venosus defect (SVD) closure with covered stents is emerging as an alternative to surgery. An adequate anchor zone in the superior vena cava is mandatory for the stability of the covered stent to prevent caudal embolization. There is a potential risk of innominate vein occlusion by the fabric of the covered stent in patients with a very short superior caval vein. Three among a total of 105 patients who underwent SVD closure at our institution developed innominate vein occlusion. Predisposing anatomical factors, identification and management of occluded innominate vein, and follow-up outcomes are discussed.