Complete Atrioventricular Defect Research Articles

A surgical approach of an unusual variant of complete atrioventricular defect; A case report

BackgroundComplete atrioventricular canal is a congenital heart defect that is characterized by an atrial septal defect, ventricular septal defect, and a common atrioventricular valve. Standard surgical techniques for repairing complete atrioventricular canal defect mainly includes repairing the defect with a single patch, a double patch, or with the modified single patch technique.Case presentationThis paper presents a novel surgical repair technique of an unusual anatomical presentation for a complete atrioventricular canal defect in a patient with Down syndrome.ConclusionsUnusual anatomical variant for congenital heart defects occurs frequently, which gives surgeons real opportunities to innovate surgical approaches. This patient was an example of an unusual anatomical presentation for complete atrioventricular canal, and the surgical technique used for this patient was novel. Follow up for these patients is mandatory for long term results.

Post-operative course of pulmonary artery pressure after complete atrioventricular canal defect repair.

The purpose of this study is to describe the evolution of pulmonary artery hypertension after repair of complete atrioventricular canal defect and to determine the time to normalisation of pulmonary artery pressure in both patients with and without Trisomy 21. This is a single centre, retrospective analysis of patients with complete atrioventricular canal defect admitted for surgical repair at the University of Maryland Medical Center from 2005 to 2015. T-test or Mann-Whitney test and Chi-Square or Fisher's exact tests were used to compare the two groups (patients with Trisomy 21 and those without). Repeated measures of analysis of variance and serial measurement analysis were performed. Twenty-nine patients meeting the inclusion criteria underwent repair of complete atrioventricular defects during the study period. The right ventricular pressure estimate remained elevated over time and did not show a significant difference between the two groups. Right ventricular to systolic blood pressure ratios for all patients remained > 0.5 over the time periods assessed. Our study suggests that in patients with complete atrioventricular canal defects, the right ventricular pressure remains elevated and does not normalise on echocardiograms performed up to one year after surgery, suggesting a sustained elevation in pulmonary vascular resistance.

Heterotaxy Syndrome in a Pediatric Cardiac Patient: A Case Report of Rare, Complex Congenital Heart Defects

BackgroundHeterotaxy syndrome, or situs ambiguous, is a multitude of thoracoabdominal congenital irregularities involving organ rearrangements across the body axis. The array of symptoms can be subdivided into either left or right isomerism, which conventionally refers to the anatomy of the designated side presenting bilaterally. While there have been approximately 266 case reports published on heterotaxy syndrome to date, no case report has documented the combination of symptoms seen in our patient, who presents with defects characteristic of both left and right isomerism.PresentationA male infant was delivered early at gestational age 37 weeks and 3 days, due to poor fetal growth. Fetal echocardiogram had been performed prior to delivery and was indicative of complex congenital heart defects, specifically heterotaxy syndrome with dextrocardia, double‐outlet right ventricle with transposed great arteries, a complete atrioventricular canal defect, a large ventricular septal defect and a large common atrium. The suspected defects were confirmed after delivery via echocardiography and cardiac catheterization. Given that heterotaxy can occur by itself or as a secondary feature of another genetic disorder, karyotyping via chromosomal array and chromosomal analysis were performed; however, no chromosomal or genetic abnormalities were identified.Results – Anatomical Features ‐Mirror image dextrocardia with the inferior vena cava and descending aorta located to the left of the spine at the level of the diaphragm ‐There is both a large septum primum and septum secundum defect, which gives rise to essentially a single common atrium, with unrestricted flow across the atrium. The anatomic right atrium is on the patient left, and the anatomic left atrium is on the patient right ‐There are bilateral superior vena cava draining into the anatomic right side of the common atrium is on the patient left. All four pulmonary veins drain into the anatomic left atrium on the patient right. There is also anomalous drainage of the inferior vena cava into the anatomic left atrium is on the patient right ‐The anatomic right ventricular on the patient left gives rise to both the aorta and main pulmonary artery – double‐outlet right ventricle. There is also is transposition of the aorta and main pulmonary artery ‐There is a complete atrioventricular defect with a single common atrioventricular valve with few chordae tendinae attached to the ventricular septum ‐There is severe pulmonary valve stenosis with no appreciable regurgitation. There is no aortic valve stenosis or regurgitation, and the aortic valve is appropriately tri‐leafletConclusionThis form of heterotaxy syndrome partially matches both right and left atrial isomerism. Double‐outlet right ventricle, malposition of the great vessels, and pulmonary and subpulmonary stenosis are typical of right atrial isomerism. In contrast, the common atrioventricular canal defect, bilateral superior vena cava, and anomalous drainage of the inferior vena cava hint at left atrial isomerism. This anatomical case reports highlights the complexity of heart development and highlights the complexity of surgical and long‐term clinical management of heterotaxy syndrome.Cardiac catheterization visualization of dextrocardia and bilateral superior vena cava draining into patients left‐side of common atriumFigure 1Echocardiography visualization of common atrium with small intact septum (yellow arrow), common atrioventricular valve (red arrow), and ventricular septal defect (purple asterisk)Figure 2

Technical performance scores are predictors of midterm mortality and reinterventions following congenital mitral valve repair.

The Technical Performance Score (TPS) has been shown to be predictive of postoperative mortality, morbidities and reinterventions following various cardiac procedures in children. We hypothesized that TPS is also a predictor of mitral valve repair outcomes. A review of patients who underwent mitral valve repair from January 2000 to December 2013 was performed. Primary repair of complete atrioventricular defect was excluded. The scores were determined according to previously published criteria based on the need for reintervention and predischarge echocardiograms: Class 1 (no residua), Class 2 (minor residua) or Class 3 (pacemaker implantation, major residua or reintervention for major residua prior to discharge). Cox proportional hazard models and Kaplan-Meier estimator were used. A total of 587 patients underwent mitral repair (median age 2.6 years). Median follow-up duration was 3 years. There were 125 (21.3%) post-discharge mitral reinterventions and freedom from reintervention was 85.2%, 78.2% and 69.4% at 1, 2 and 5 years, respectively. Both TPS Class 2 [hazard ratio (HR) 3.6, 95% confidence interval (CI) 1.4-10.0; P = 0.02] and Class 3 (HR 8.7, 95% CI 3.0-25.1; P < 0.001) were associated with post-discharge reinterventions. There were 31 late deaths/transplantations, and transplant-free survival at 1, 2 and 5 years was 97.8%, 95.3% and 93.2%. TPS 3 was associated with decreased post-discharge transplant-free survival (HR 5.5, 95% CI 1.2-25.0; P = 0.03). Post-discharge mitral reintervention was not associated with increased mortality. The TPS is a strong predictor of midterm mortality and post-discharge mitral reintervention in congenital patients who underwent mitral repair.

Repair of Atrioventricular Septal Defects: The 2-Patch Sandwich Technique

The key elements in the 2-patch method of repair of complete atrioventricular defects include: (1) closure of the ventricular defects using a Dacron patch, (2) closure of the primum atrial defect using an autologous pericardial patch, and (3) securely partitioning the atrioventricular valves into competent left and right components. With limited exceptions, there is sufficient conservation of morphological features of the atrial and ventricular defects as well as that of the atrioventricular valves to allow standardization of the key elements of the surgical repair.

REPAIR FOR PARTIAL AND COMPLETE ATRIOVENTRICULAR SEPTAL DEFECT: SINGLE CENTRE EXPERIENCE AND LONG-TERM RESULTS

The number of adult patients with surgical repaired congenital heart defects increases continuously. We were interested to compare late outcome after partial and complete atrioventricular defect repair (pAVSD and cAVSD, respectively) and to determine the most important reason for re-intervention. All patients older than 16 years, who underwent partial or complete atrioventricular defect repair, were selected from the database. The medical files were reviewed for descriptive statistics. Kaplan Meier analysis was used to determine event free survival for both groups. Log rank testing was performed where applicable. One hundred thirty-eight patients were included. Two patients in each group with early post-operative mortality were excluded (pAVSD: 33/30 male/female, mean age 35.9 +/- 15.6 years; cAVSD: 27/ 44 male/female, mean age 25.7 +/- 11.9 years). Fourteen pAVSD-patients and 23 cAVSD-patients needed a surgical re-intervention: in two and 13 patients, respectively, a mitral valve repair was performed, and in five and one patient, respectively, a mechanical valve was replaced. Eight cAVSD-patients and 10 pAVSD-patients developed atrial arrhythmias. Seven patients (3 cAVSD and 4 pAVSD) received a pacemaker. Median event-free survival time was significantly shorter in the cAVSD-group (22.9 (95% CI 15.4-30.5) years) when compared to the pAVSD-group (34.0 (95% CI 20.1-47.9) years) (Log rank testing, P=0.017). Late outcome was characterized by a longer event free follow-up time of pAVSD-patients when compared to cAVSD-patients. The most important reason for re-intervention in both groups was mitral valve regurgitation. However, atrial arrhythmias and conduction disorders were not uncommon late after atrioventricular septal defect repair.

Communications interventriculaires

Isolated ventricular septal defect (VSD) is the most common congenital cardiac malformation. VSD is also the most frequent defect associated to others congenital cardiovascular malformations. The numerous anatomic varieties of VSD explain the great variability of the clinical features and the differences in the natural history. With echocardiography and colour Doppler, the diagnosis of VSD is easier and more accurate than previously; so, pre-operative catheterization is no longer needed in most of the cases. The course of VSDs, depending on their size and location, may be early predicted in analysing their anatomic aspect by repeated echocardiography Doppler during the first months of life. Most of them become proportionally smaller with time and, finally, close spontaneously during infancy, childhood or adolescence. Few VSDs need early surgical closure to avoid complications of a large left-to-right shunt, such as cardiac failure and pulmonary hypertension secondary to a severe damage of pulmonary arteries. This management prevents Eisenmenger's syndrome, an irreversible situation corresponding to an inversion of the shunt in relation to high pulmonary vascular resistance. When VSD persists in adults, others complications such as infective endocarditis and aortic regurgitation may occur; therefore, strict surveillance and antibiotic prophylaxis are recommended in concerned patients. Owing to the improvement of cardiac surgery in low weight infants, the surgical closure of large VSD in infancy gives currently excellent results. Apical muscular VSD and multiple muscular VSD still present a particular surgical challenge: today, their closure may be achieved using a ventricular septal device during surgery or interventional catheterization. In this article, only isolated VSDs will be considered. Indeed, VSDs that constitute an integral part of a more complex malformation, such as the “tetralogie de Fallot” or complete atrio-ventricular defect, have a different presentation and require a specific treatment. Persistent VSD after correction of another cardiac malformation (aortic coarctation, transposition of great arteries, etc .) may be assimilated to isolated VSDs because they have usually similar clinical features and outcome.

Correlation between pulmonary vascular change and hemodynamics in patients with complete atrioventricular septal defect.

The study of the pulmonary vasculature in Taiwanese with atrioventricular septal defect has not been reported previously. This study investigated the correlation between pulmonary vascular change and hemodynamics in these patients. Ten children with complete atrioventricular defect, 8 of whom had Down syndrome, underwent open lung biopsy. Their age ranged from 8 months to 6 years (mean, 2 years 7 months). Cardiac catheterization was performed and the systolic pressures of pulmonary and systemic arteries were measured immediately before cardiopulmonary bypass (CPB) and immediately after cardiac repair in 9 patients, and expressed as a ratio of pulmonary to systemic systolic pressure (Pp/Ps). Medial hypertrophy and intimal proliferation were prominent in 7 patients with pulmonary hypertension. The alveolar wall muscular arteries and percent arterial medial thickness increased significantly with increasing post-repair Pp/Ps, preoperative Pp/Ps, pulmonary arteriolar resistance index and pre-CPB Pp/Ps (p < 0.02). The arteries present per 100 alveoli were inversely correlated with the above mentioned hemodynamic parameters (p < 0.02). The results of qualitative and quantitative analyses of the pulmonary vasculature in patients with complete atrioventricular defect correlated well with pre-and postoperative pulmonary arterial pressure and can be used to predict the postoperative pulmonary arterial pressure.

Actuarial survival, freedom from reoperation, and other events after repair of atrioventricular septal defects

Repair of an atrioventricular septal defect was performed in 134 patients from 1973 to 1985. Interventricular communication was present in 54 (40%) and none was present in 80 (60%). There were 12 hospital deaths (9%; 70% confidence limits 6%-12%). Earlier date of operation (p = 0.03) and younger age at repair (p = 0.005) were incremental risk factors for hospital death after repair of partial atrioventricular septal defect. Smaller size (p = 0.003) and longer cross-clamp time (p = 0.002) were risk factors for hospital death in those patients with complete atrioventricular septal defect. Higher preoperative pulmonary vascular resistance was a risk factor for death in both groups (p = 0.007). The 10 year actuarial survival rate was 82% overall. Increasing preoperative severity of left atrioventricular valve incompetence was not a risk factor for early (p = 0.001) or late (p = 0.002) death. The 10 year actuarial freedom from reoperation after repair of partial atrioventricular defects was 85%, and it was 68% for complete atrioventricular defects (p = 0.06). We conclude that the intermediate term results after repair of atrioventricular septal defects are good. Incompetence of the left atrioventricular valve has apparently been neutralized as a risk factor for hospital death in this series. However, the durability of the repair has been disappointing. A policy of earlier repair has been adopted and should improve hospital mortality and permit better preservation of the atrioventricular valve structures with resultant improved late term functional status.

Postoperative pathology of complete atrioventricular defects

Necropsy data on 15 patients, who died after operations for complete atrioventricular defect (CAVD), were reviewed in order to analyze the possible determinants of death. Two infants had undergone a palliative procedure--pulmonary artery banding (Group I); three patients had had prosthetic replacement of one or both atrioventricular (AV) valves (Groups II); and the remaining 10 had had conservative repair with plastic reconstruction of the AV valves (Group III). The most notable pathological findings related to death were as follows: Group I, left ventricular hypoplasia in both infants; Group II, prosthetic dysfunction in all patients; Group III, extracardiac diseases in two-patients and cardiac lesions in six. In Group III severe pulmonary vascular obstructive disease (PVOD) was observed as an isolated finding in two patients and in combination with residual intracardiac anomalies in another two. Analysis of the incidence of PVOD demonstrated that irreversible changes may occur within the first year of life in babies with Down's syndrome, and that these changes well correlate with the calculated pulmonary vascular resistance (PVR) values. From the results of this study we have reached the following conclusions: (1) Prosthetic valve replacement has to be avoided because of a high incidence of prosthesis-related complications and the effectiveness of conservative repair; (2) residual untreated anomalies may affect the outcome of operation and should be accurately recognized and weighted preoperatively; (3) PVOD can occur in CAVD even before the first year of life and can be reliably assessed by the measurement of PVR. High degrees of PVOD frequently interfere with the surgical success, particularly when residual intracardiac anomalies are present. Therefore, we suggest that surgical correction be planned, when indicated, during the first 6 months of life.

Subxiphoid M-mode echocardiography in atrioventricular defects.

M-mode echocardiograms obtained using the subxiphoid position of the transducer were compared with those obtained using the parasternal position in 21 children with atrioventricular defects. In the 16 children with complete atrioventricular defect, it was always possible to demonstrate a common valve orifice wholly occupying the space between the anterior and posterior cardiac walls with no interventricular septal tissue in the plane of the orifice. Scanning between the plane of this orifice and the ventricular cavity demonstrated a ventricular septum in all cases, separating components of the atrioventricular valve apparatus from each other, corroborating the impression that the valve was straddling the ventricular septum and, therefore, that the valve was common to both ventricles. No septal tissue was detected in scans ranging between the aortic valve and the common orifice in these 16 children. In the five children with partial atrioventricular defects, two atrioventricular orifices separated by septum could be demonstrated. The subxiphoid approach in these 21 children defined the anatomy of atrioventricular defects more clearly and more readily than the parasternal approach.

Angiocardiographic appearances of atrioventricular defects with particular reference to distinction of ostium primum atrial septal defect from common atrioventricular orifice.

Preoperative distinction between common atrioventricular orifice and ostium primum atrial septal defect may be difficult. To improve diagnostic accuracy, the right and left ventricle angiocardiograms were reviewed 'blind' in 92 patients with atrioventricular defects. The true diagnosis was known from necropsy or surgery in 60. Angiocardiograms had been obtained in various projections with or without craniocaudal tilt. Those features thought to distinguish between common orifice and ostium primum were coded, together with the ventricular systolic pressures. Computerised disciminant function analysis identified the following distinguishing features: (1) right ventricular systolic pressure; (2) immediate right ventricular outflow tract opacification from the left ventricle; (3) identification of the anterior attachment of the mitral component; (4) recognition of a single straddling atrioventricular orifice; (5) passage of contrast medium above or below the anterior or posterior bridging leaflets. Feature (3) indicates that in contrast to classic teaching the direct septal attachment of the mitral component does not contribute to the 'gooseneck' in complete atrioventricular defects. The significance of (4) and (5) is that they may be identified from right as well as left ventriculography, and are more likely to be identified in oblique than standard projections. Computerisation produced a correct diagnosis in 92 per cent of known cases, and determined precise probabilities of diagnosis in the remainder.

Morphology and classification of complete atrioventricular defects.

Anatomical studies were made on 70 necropsied hearts with atrioventricular defects from patients with situs solitus and atrioventricular concordance, all having a common atrioventricular orifice. The arterial connections were concordant in 68 and were double outlet right ventricle in two; cases with arterial discordance (transposition) or single outlet of the heart were excluded. It proved possible to subdivide the hearts, depending on the morphology of the valve leaflets. Five leaflets were distinguished by the commissural pattern and their insertion to major papillary muscles. They were a posterior bridging leaflet, right and left lateral leaflets, and right and left anterior leaflets. Subdivision was made on the basis of the disposition of the anterior leaflets. In six hearts the left anterior leaflet was committed to the left ventricle and the right anterior leaflet to the right ventricle, the commissure between them being on the crest of the ventricular septum. In 39 hearts there was minimal bridging of the left anterior leaflet so that it extended between the anterior papillary muscle of the left ventricle and the medial papillary complex of the right ventricle. In eight hearts the right margin of the left anterior leaflet was attached to an apical papillary muscle, while in 17 hearts it was attached to the anterolateral papillary muscle of the right ventricle. As the bridging of the left anterior leaflet increased, so the size of the right anterior leaflet decreased, but in all hearts both leaflets were identified. These findings were compared with previous classifications of complete atrioventricular defects.