Atrioventricular Septal Defect: What Is in a Name?

Efficacy of atrioventricular valve regurgitation in the first trimester for the diagnosis of atrioventricular septal defect

PURPOSE

To investigate the efficacy of atrioventricular valve regurgitation (AVVR) for predicting atrioventricular septal defect (AVSD) in the first trimester.

METHODS

We performed a prospective observational study, screening for complicated congenital heart diseases and AVVR in fetuses at 11 to 13+6 weeks of gestation by advanced dynamic flow in four-chamber view and three-vessel-trachea view.

RESULTS

43 549 fetuses at 11 to 13+6 weeks of gestation were screened by echocardiography, of which 37 cases were diagnosed with AVSD, including complete AVSD (31 cases), intermediate AVSD (3 cases) and partial AVSD (1 cases), undiagnosed intermediate AVSD (2 cases), and misdiagnosed case (2 cases). AVVR was observed in 34 cases (34/37) in the first trimester, 59. 46% (22/37) nuchal translucency greater than 95th percentile, 29. 73% (11/37) absence of nasal bone, 32. 43% (12/37) ductus venosus A wave inversion, and 40. 54% (15/37) had tricuspid regurgitation. The sensitivity of common AVVR in predicting AVSD is better than other ultrasonic indexes.

CONCLUSIONS

AVVR can be used as an ultrasonic indicator to predict AVSD in the first trimester, which is beneficial to detect AVSD.

RNA binding proteins in cardiovascular development and disease

Congenital heart disease (CHD) is the most common birth defect affecting>1.35 million newborn babies worldwide. CHD can lead to prenatal, neonatal, postnatal lethality or life-long cardiac complications. RNA binding protein (RBP) mutations or variants are emerging as contributors to CHDs. RBPs are wizards of gene regulation and are major contributors to mRNA and protein landscape. However, not much is known about RBPs in the developing heart and their contributions to CHD. In this chapter, we will discuss our current knowledge about specific RBPs implicated in CHDs. We are in an exciting era to study RBPs using the currently available and highly successful RNA-based therapies and methodologies. Understanding how RBPs shape the developing heart will unveil their contributions to CHD. Identifying their target RNAs in the embryonic heart will ultimately lead to RNA-based treatments for congenital heart disease.

Application of neural networks in prenatal diagnosis of atrioventricular septal defect

Background

There is no relevant study on landmarks detection, one of the Convolutional Neural Network algorithms, in the field of fetal echocardiography (FE). This study aimed to explore whether automatic landmarks detection could be used in FE correctly and whether the atrial length (AL) to ventricular length (VL) ratio (AVLR) could be used to diagnose atrioventricular septal defect (AVSD) prenatally.

Methods

This was an observational study. Two hundred and seventy-eight four-chamber views in end diastole, divided into the normal, AVSD, and differential diagnosis groups, were retrospectively included in this study. Seven landmarks were labeled sequentially by the experts on these images, and all images were divided into the training and test sets for normal, AVSD, and differential diagnosis groups. U-net, MA-net, and Link-net were used as landmark prediction neural networks. The accuracy of the landmark detection, AL, and VL measurements, as well as the prenatal diagnostic effectiveness of AVLR for AVSD, was compared with the expert labeled.

Results

U-net, MA-net, and Link-net could detect the landmarks precisely (within the localization error of 0.09 and 0.13 on X and Y axis) and measure AL and VL accurately (the measured pixel distance error of AL and VL were 0.12 and 0.01 separately). AVLR in AVSD was greater than in other groups (P<0.0001), but the statistical difference was not obvious in the complete, partial, and transitional subgroups (P>0.05). The diagnostic effectiveness of AVLR calculated by three models, area under receiver operating characteristic curve could reach 0.992 (0.968-1.000), was consistent with the expert labeled.

Conclusions

U-net, Link-net, and MA-net could detect landmarks and make the measurements accurately. AVLR calculated by three neural networks could be used to make the prenatal diagnosis of AVSD.

Role of ECG in the Accidental Finding of an Atrioventricular Septal Defect in an Asymptomatic Patient Undergoing Cosmetic Surgery

Electrocardiogram (ECG) is an important diagnostic tool in identifying congenital heart disease (CHD), as demonstrated by this case of a 48-year-old female who presented for a preoperative evaluation for cosmetic surgery. ECG showed a right bundle branch block (RBBB) and first-degree atrioventricular (AV) block, and further testing revealed a primum atrial septal defect (ASD) with mitral valve anterior leaflet cleft and a membranous ventricular septal defect (VSD). She underwent successful surgical repair and was discharged home without complications. This case highlights the importance of performing additional tests like echocardiography or other imaging modalities in cases of abnormal ECG findings to accurately diagnose the underlying heart condition and ensure proper treatment.

Left Atrioventricular Transvalvular Pressure Gradients Derived from Intraoperative and Postoperative Echocardiograms following Atrioventricular Septal Defect Repair

BACKGROUND

Left atrioventricular valve (LAVV) stenosis following an atrioventricular septal defect (AVSD) repair is a rare but potentially life-threatening complication. While echocardiographic quantification of diastolic transvalvular pressure gradients is paramount in the evaluation of a newly corrected valve function, it is hypothesized that these measured gradients are overestimated immediately following a cardiopulmonary bypass (CPB) due to the altered hemodynamics when compared to postoperative valve assessments using awake transthoracic echocardiography (TTE) upon recovery after surgery.

METHODS

Out of the 72 patients screened for inclusion at a tertiary center, 39 patients undergoing an AVSD repair with both intraoperative transesophageal echocardiograms (TEE, performed immediately after a CPB) and an awake TTE (performed prior to hospital discharge) were retrospectively selected. The mean (MPGs) and peak pressure gradients (PPGs) were quantified using a Doppler echocardiography and other measures of interest were recorded (e.g., a non-invasive surrogate of the cardiac output and index (CI), left ventricular ejection fraction, blood pressures and airway pressures). The variables were analyzed using the paired Student's t-tests and Spearman's correlation coefficients.

RESULTS

The MPGs were significantly higher in the intraoperative measurements when compared to the awake TTE (3.0 ± 1.2 vs. 2.3 ± 1.1 mmHg; p < 0.01); however, the PPGs did not significantly differ (6.6 ± 2.7 vs. 5.7 ± 2.8 mmHg; p = 0.06). Although the assessed intraoperative heart rates (HRs) were also higher (132 ± 17 vs. 114 ± 21 bpm; p < 0.001), there was no correlation found between the MPG and the HR, or any other parameter of interest, at either time-point. In a further analysis, a moderate to strong correlation was observed in the linear relationship between the CI and the MPG (r = 0.60; p < 0.001). During the in-hospital follow-up period, no patients died or required an intervention due to LAVV stenosis.

CONCLUSIONS

The Doppler-based quantification of diastolic transvalvular LAVV mean pressure gradients using intraoperative transesophageal echocardiography seems to be prone to overestimation due to altered hemodynamics immediately after an AVSD repair. Thus, the current hemodynamic state should be taken into consideration during the intraoperative interpretation of these gradients.

Isolated Balanced Complete Atrioventricular Septal Defects: Prenatal Detection and Outcome in Nevada

We analyzed patients with isolated, balanced complete atrioventricular septal defects. We identified 71 patients born in Nevada, between January 2008 and December 2020. We also analyzed prenatal detection rates. Of the 71, 61 (85%) had trisomy 21, 1 (1%) had CHARGE syndrome and 22q.11 deletion, and 10 (14%) had no chromosomal abnormalities. Of the 71, 67 had prenatal care, and 43/67 (64%) were prenatally diagnosed. Prenatal detection rate for 2008-2012 was 9/20 (45%) and 18/21 (86%) for 2018-2020, P = .03. Of the 71, 67 underwent surgical repair with 1 current postpulmonary artery banding and 0 surgical deaths. Of the 67, 3 (4%) had heart block. Only 1 (1.5%) patient had reoperation for a mitral valve replacement. Of the 71, 67 (94%) are alive during a 6-year average (range = 0-12 years) follow-up. In conclusion, surgical and long-term outcomes were excellent. Also, high state-wide, general population prenatal detection rates were achieved.