The V-shaped double-layer patch technique for complete atrioventricular septal defect: A novel surgical technique

OBJECTIVE

Several surgical techniques for repair of a complete atrioventricular septal defect have been developed. However, the postoperative complications with these methods may lead to reoperation during follow-up. The aim of this report is to share our experience with a modified surgical technique for complete atrioventricular septal defect that has anatomic advantages postoperatively and could reduce the reoperation rate.

METHODS

Twenty-nine patients who underwent repair of complete atrioventricular septal defect using a V-shaped double-layer patch between April 2011 and September 2019 were retrospectively investigated.

RESULTS

There were no deaths (0%) and only 1 reoperation (3.4%) in the series. The aortic crossclamp and cardiopulmonary bypass times were 62.7 ± 16.0 minutes and 113.9 ± 25.9 minutes, respectively. The median follow-up duration was 5.1 years. To date, no significant residual ventricular septal defects have been detected and no left ventricular outflow tract obstruction has been seen on echocardiography in any patient. During follow-up, the left atrioventricular valve status was assessed as no incompetence in 9 patients (31.0%), trivial in 18 patients (62.1%), and mild in 2 patients (6.9%).

CONCLUSIONS

The V-shaped double-layer patch technique is a valuable surgical option for patients with complete atrioventricular septal defects. The midterm results in our series document excellent performance of this technique, which augments the area of the anterior valve of the left atrioventricular valve to make it closer to a normal mitral valve and may also reduce the need for reoperation.

Surgical Management for Complete Atrioventricular Septal Defects: A Systematic Review and Meta-Analysis

A meta-analysis is performed for a comparison of outcomes between the modified one-patch repair (MPR) and two-patch repair (TPR) for complete atrioventricular septal defects (CAVSD). Electronic databases, including PubMed, Scopus, Embase, and Cochrane Library were searched systematically for the literature which aimed mainly at comparing the therapeutic effects for CAVSD administrated by MPR and TPR. Corresponding data sets were extracted and two reviewers independently assessed the risks of bias. Meta-analysis was performed using Revman 5.3 and Stata 12.0. Fifteen studies meeting the inclusion criteria were included, involving 2076 subjects in total. It was observed that MPR was associated with shorter cardiopulmonary bypass (CPB) and aortic cross-clamp (ACC) times, as compared with TPR. However, no statistical differences were found in terms of size of ventricular septal defects (VSD), reoperation, mortality, implantation of permanent pacemakers, and length of ventilation, hospital and intensive care unit stay. As compared with TPR, MPR is superior in terms of ACC and CPB. However, with regard to reoperation, mortality, length of ventilation, ICU and hospital stay and permanent pacemakers implantation, no significant differences are found between these two procedures. MPR is likely to apply to younger infants with faster completion of surgery. Surgery is recommended between 3 and 6 months of age.

Modified Single-Patch Technique Versus Two-Patch Technique for the Repair of Complete Atrioventricular Septal Defect: A Meta-Analysis

Technical selection for surgical repair of complete atrioventricular septal defect (CAVSD) still remains controversial. This meta-analysis aimed to compare the modified single-patch (MP) technique with the two-patch (TP) technique for patients with CAVSD. Relevant studies comparing the MP technique with the TP technique were identified through a literature search using MEDLINE, EMBASE, Google Scholar, Cochrane Library, and the China National Knowledge Infrastructure databases. The variables were ventricular septal defect (VSD) size, cardiopulmonary bypass (CBP) time, aortic cross-clamp (ACC) time, intensive care unit stay, hospital stay, and other outcomes involving mortality, left ventricular outflow tract obstruction, atrioventricular valve regurgitation, residual septal shunt, atrioventricular block, and reoperation. A random-effect/fixed-effect model was used to summarize the estimates of mean difference/odds ratio with 95% confidence interval. Subgroup analysis stratified by region was performed. Fifteen publications involving 1034 patients were included. This meta-analysis demonstrated that (1) VSD size in the MP group was significantly smaller; (2) CBP time, ACC time, and hospital stay in the MP group experienced improvement; (3) Other postoperative outcomes showed no significant differences between two groups; and (4) The trends in China and other countries were close. The MP and TP techniques had comparable outcomes; however, the MP technique was performed with significantly shorter CBP and ACC times in patients with smaller VSDs. Given this limitation of data, the results of comparison of the two techniques in patients with larger VSDs remain unknown. Further studies are needed.

Surgical repair of complete atrioventricular defect (Nunn technique)

Two procedures have been traditionally used for the surgical repair of complete atrioventricular canal. The single-patch technique includes the division of valve leaflets, and the use of one patch to close the ventricular and the atrial septal defects, whereas the double-patch technique uses two separate patches, without the division of the bridging leaflets. Between 1997 and 2007, another technique emerged, the modified single-patch technique, or the 'Australian' technique, whereby the ventricular septal defect (VSD) is closed by the direct apposition of the bridging leaflets against the crest of the defect. Because of the absence of the ventricular septal patch, concerns have been raised about the possible left ventricular outflow tract obstruction (LVOTO), or atrioventricular valve (AVV) distortion, especially in case of a deep VSD, or if the defect extends superiorly. The results of the modified single-patch technique in terms of mortality, immediate and long-term AVV function and LVOTO have been similar to the standard techniques in most reports. This article will describe in detail the operative technique and review the relevant literature.