Comparison of two surgical techniques for complete atrioventricular septal defect repair using two- and three-dimensional echocardiography

Echocardiographic Evaluation of Postoperative Coaptation Geometry of Left AV Valve in Complete Atrioventricular Septal Defect

Background:

We sought to determine the difference in geometric parameters in the left atrioventricular valve (LAVV) postoperative complete atrioventricular septal defect (CAVSD) compared to the normal heart, and the correlation between geometric and functional parameters for detecting the mechanism of LAVV regurgitation (LAVVR) in CAVSD.

Methods:

LAVV geometric parameters based on complete and acceptable quality echocardiograms of 18 patients with repaired CAVSD compared with 17 normal controls. LAVVR severity was also quantified by indexed vena contracta (I-VC) (mm) and % jet area/left atrium area (% Jet/LA), and the correlation with LAVV parameters in the CAVSD group was investigated.

Results:

In the CAVSD group, the posterior closing angle (Pc) was nearly the same as the anterior closing angle (Ac), yet in the normal heart, the Pc angle was double the Ac angle. The anterior opening angle (Ao) and posterior-to-anterior leaflet diameter ratio (a/p) in the CAVSD group was also significantly smaller. The CAVSD group also had a shorter indexed coaptation length (I-CL) and indexed tenting height (I-TH). Displacement length (ΔD) differed completely between the CAVSD and Normal groups, and also showed a strong positive correlation to the functional parameters of LAVVR (% Jet/LA: r = .70, P = .02; I-VC: r = .60, P = .02).

Conclusions:

The parameters in this study were applicable to CAVSD AV valve coaptation characteristics. We introduced 2 novel measures that may provide important insights into the differences in geometry and performance of the LAVV in repaired CAVSD as compared to normal hearts.

Correlation of ventricular septal defect height and outcomes after complete atrioventricular septal defect repair

 

OBJECTIVES

There are limited data available on the height of the ventricular component of the septal deficiency (VSD) in patients undergoing complete atrioventricular septal defect (CAVSD) repair. VSD height may influence optimal choice of repair strategy with potential consequences for long-term outcomes. We aimed to measure VSD height using 2-dimensional echocardiography and review its association with postoperative outcomes.

METHODS

We retrospectively reviewed the preoperative echocardiograms of 45 consecutive patients who underwent CAVSD repair between May 2010 and December 2015 at a single centre. VSD height and left ventricular length on the four-chamber view were measured. Demographic details and early and late outcomes including reoperation and long-term survival were studied.

RESULTS

Twenty patients underwent modified single-patch repair and 25 patients underwent double-patch repair of CAVSD. VSD height in the modified single-patch group ranged from 4.2 to 11.7 mm and in the double-patch group ranged from 5.1 to 14.9 mm. Nine patients had a deep ‘scoop’ with a VSD height of >10 mm, (7 double patch, 2 modified single patch). VSD height did not correlate with a specific Rastelli classification. There was no significant difference in the VSD height (P = 0.51) or the VSD height-to-left ventricular length ratio (P = 0.43) between the 2 repair groups. There was no 30-day mortality. Eight patients required reoperation; however, VSD height was not a significant predictor of reoperation (hazard ratio 0.95, 95% confidence interval 0.69–1.33; P = 0.08).

CONCLUSIONS

There was no correlation between VSD height and risk of reoperation after CAVSD repair. A deep ventricular scoop is uncommon in CAVSD patients.

Atrioventricular Septal Defects: Pathology, Imaging, and Treatment Options

PURPOSE OF REVIEW

Atrioventricular septal defects (AVSD) represent a broad spectrum of congenital anomalies from simple to the most complex heart defects including some distinct types. Clinical presentation and timing of intervention differ by morphological subset and functional anatomy. Herein, we review morphological variations and characteristics that determine appropriate intervention and provide insights into functional anatomy based on detailed three-dimensional (3D) assessment of AVSDs.

RECENT FINDINGS

The understanding of functional morphology of AVSDs has improved significantly with detailed 3D echocardiographic evaluation of the atrioventricular junction and valve morphology. As prenatal detection of AVSDs has increased significantly, it has become the most common fetal cardiac diagnosis enabling antenatal counseling and delivery planning. Advances in diagnosis and perioperative care have resulted in optimal outcomes. The diagnosis and management of AVSDs have improved over the years with enhanced understanding of anatomy and perioperative care resulting in optimal short and long-term outcomes.

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 Repair Technique for Complete Atrioventricular Septal Defect: A Propensity Score Matching Analysis

There were controversies about the priority of modified single patch (MSP) technique compared with two-patch (TP) technique for patients with complete atrioventricular septal defect (CAVSD). From 2002 to 2013, patients who diagnosed as balanced CAVSD in our institution were retrospectively included. Patients with unbalanced ventricles or associated anomalies were excluded. The primary endpoint was all-cause mortality and the secondary endpoint consist of left atrioventricular dysfunction or left atrioventricular outflow tract obstruction (LVOTO). A total of 74 patients underwent MSP repair and 102 patients underwent TP repair. After 1:1 propensity matching, there were 46 Rastelli type A CAVSD patients in each group. Patients in MSP group had shorter cardiopulmonary bypass time [median (interquartile range) 73.5 (65.5-95.0) versus 105.0 (88.8-130.0) min, P < 0.001] and aortic cross-clamp time [105.5 (90.0-128.0) versus 143.0 (122.0-184.0) min, P < 0.001]. In total, the primary endpoint occurred in 12 patients, including 2/46 (4.3%) in MSP group and 10/46 (21.7%) in TP group. That 1-year, 3-year, 5-year survival rate can be calculated as 95.6%, 95.6%, 95.6% in MSP group and 92.6%, 80.4%, 78.2% in TP group, P = 0.015. No significant statistical difference found for the secondary endpoints that 7/46 (15.2%) patients occurred moderate or severe LAVVR in MSP group versus 11/46 (23.9%) patients in TP group, P = 0.293. No LVOTO occurred in both groups. Besides the simplicity of technique, MSP technique may be safer.

Modified Single-Patch versus Two-Patch Repair for Atrioventricular Septal Defect: A Systematic Review and Meta-Analysis

BACKGROUND

We performed a meta-analysis of studies to determine whether the modified single-patch technique offers benefits when compared to the two-patch repair. The postoperative outcomes examined in this study were cardiopulmonary bypass time, cross-clamp time, duration of mechanical ventilation, intensive care unit length of stay, total hospital length of stay, need for reoperation, need for reoperation for left ventricular outflow tract obstruction or left atrioventricular valve regurgitation, need for pacemaker implantation, and mortality during follow-up.

METHODS

A review was conducted to identify studies comparing a modified single-patch repair versus two-patch repair. A fixed-effects model was utilized for end points with low heterogeneity and a random-effects model for end points with significant heterogeneity. Meta-regression was also performed to determine the influence of other factors on the variables of interest.

RESULTS

A total of 964 unique manuscripts were screened, with 10 being included in the final analyses. There were a total of 724 patients, with 353 (49%) having undergone repair utilizing a modified single-patch repair. Mean age at repair for modified single-patch repair and two-patch repair was 8.81 and 9.03 months, respectively. Significant differences were noted in cardiopulmonary bypass time and cross-clamp time with mean difference of -28.53 and -22.69 minutes, respectively. In comparison to the two-patch repair, both times were decreased in modified single-patch repair. No significant difference was noted in any other variables.

CONCLUSIONS

Modified single-patch repair for atrioventricular septal defects requires less cardiopulmonary bypass and cross-clamp time but does not significantly impact the examined postoperative outcomes.

Modified-Single Patch vs Double Patch Repair of Complete Atrioventricular Septal Defects

Biventricular repair of complete atrioventricular septal defect (CAVSD) is largely achieved using the double-patch (DP) or modified single-patch (MSP) techniques in the current era; however, long-term results following MSP repair are not well defined. We aimed to compare long-term outcomes including reoperation and mortality after CAVSD repair using DP and MSP techniques, and identify the risk factors associated with adverse outcomes. A retrospective cohort study was performed including all patients who underwent CAVSD repair using DP and MSP techniques at our institution between 17 May 1990 and 14 December 2015. Demographic details, early (≤30 days) and late (>30 days) outcomes (reoperation, mortality) were studied. Competing risks analysis with cumulative incidence function was used for survival analyses. Overall, 273 consecutive patients underwent CAVSD repair (120 DP and 153 MSP) and 41 patients required reoperation during follow-up. Competing risks analysis showed no association between repair technique and reoperation (P = 1.0) or mortality (P = 0.9). Considering competing risks due to mortality, the cumulative incidence of reoperation at 5, 10, and 15 years was 14%, 17%, and 17% for DP and 12%, 13%, and 16% for MSP, respectively. Non-Down syndrome and moderate or greater left atrioventricular valve regurgitation were predictors for reoperation. Pulmonary artery banding was predictive of mortality, though strongly associated with earlier surgical era. Median follow-up duration was 8.0 years (interquartile range 3.9-20.8) for DP and 11.6 years (interquartile range 5.4-16.1) for MSP (P = 0.4). Event-free survival is similar after DP and MSP repair of CAVSD indicating either repair technique can be safely utilized.

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.