Aortic atresia with a ventricular septal defect: modified single-stage neonatal biventricular repair

Aortic Atresia or Complex Left Outflow Tract Obstruction in the Presence of a Ventricular Septal Defect

Severe left outflow tract obstruction (LVOTO) is not always associated with hypoplastic left heart syndrome (HLHS). Aortic valvar atresia or complex LVOTO in the presence of a large ventricular septal defect (VSD) are a rare group of lesions that offer the possibility of biventricular repair. The Yasui procedure is the commonest surgical approach which can be performed as a primary neonatal correction or as a staged procedure with a Norwood followed by a subsequent Rastelli. This article reviews the surgical outcomes and decision-making process. Both strategies are reasonable with the trend toward staged procedure in the setting of the additional interrupted arch, with neonatal survival of > 90% in the modern era and excellent long-term survival. Re-intervention is mostly related to conduit revision and the need for re-operation for LVOTO is rare. Deciding between conventional repair and the Yasui in cases of LVOTO/VSD can be difficult and there are no uniform accepted criteria. In a typical neonate, an aortic annulus < 4.5 mm is generally the limit of acceptability for a conventional repair. In selected cases of LVOTO/VSD, an alternative to the Yasui is the Ross-Konno. Retrospective comparisons between the 2 techniques are difficult due to differing patient characteristics (especially associated with mitral valve disease) but the neonatal Ross has been associated with higher early mortality.

A review of the Yasui operation with long-term follow-up of a case

Yasui operation combines Norwood arch reconstruction with Rastelli operation for interrupted or hypoplastic aorta with aortic valvar atresia or hypoplasia with ventricular septal and two adequately sized ventricles, establishing biventricular repair. We present a case of aortic atresia, mitral hypoplasia, and ventricular septal defect (VSD) treated by Yasui procedure, and its long-term (108 months) follow-up and brief review of literature. Review of literature was done using keywords to search on "PubMed" and "Google Scholar."

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-021-01174-5.

Damus-Rastelli Procedure for Biventricular Repair of Aortic Atresia and Hypoplasia

BACKGROUND

Biventricular repair (BVR) can be achieved in aortic atresia with ventricular septal defect (VSD) by creating a double outlet left ventricle, Damus-Kaye-Stansel procedure and placement of a right ventricular-pulmonary artery conduit. This study is a review of 15 years experience with this "Damus-Rastelli" technique to assess clinical outcomes in comparison with a standard univentricular approach.

METHODS

A review of 16 patients with aortic atresia or complex left ventricular outflow tract obstruction who underwent BVR between 1990 and 2005; a comparison with outcomes for the Norwood I procedure over the same period.

RESULTS

Early mortality was 19% (3 patients) with no deaths in the last 12 years (13 patients). Twelve patients had associated aortic interruption (56%) or coarctation (19%). Anatomic subtype was not a risk for early death. Late age at operation was the only risk factor identified for early death (p = 0.01). Median follow-up was 32 (range, 4 to 190) months. Actuarial survival at one and five years was 60% and 53%, respectively. This compares with an early mortality of 29% (p < 0.01) and actuarial survival of 58% and 50% in the Norwood group. Freedom from reintervention was 68% and 20% at one and five years, respectively. One patient required balloon dilatation of recurrent coarctation, all others were balloon dilatation (n = 2) or surgical (n = 4) conduit replacement. All survivors are currently in New York Heart Association class I.

CONCLUSIONS

Biventricular repair of aortic atresia and VSD can be achieved with results that compare well with univentricular palliation. Despite the need for conduit change, the long-term benefit of a BVR would support this technique. Delay in performing the initial repair may increase mortality.

Revisiting animal models of aortic stenosis in the early gestation fetus

BACKGROUND

Mechanisms leading to left ventricular hypoplasia and endocardial fibroelastosis in the fetus remain unknown. Prevailing theory is that obstruction to blood flow through the left ventricle leads to elevated end-diastolic pressures, compromised myocardial perfusion, and endocardial ischemia. Fetal interventions are now being performed, based on the presumption that they would prevent such pathogenic mechanisms.

METHODS

Forty first-trimester fetal sheep (mean gestational age, 53 days) were studied. Severe fetal left ventricular outflow obstruction was created by banding the ascending aorta in 25 fetuses; 15 control fetuses underwent "sham" surgery with thoracotomy. Serial fetal echocardiography was used to assess left ventricular growth and fetal hemodynamics. Findings were correlated to morphologic and histopathologic changes, and intracardiac pressure measurements obtained from fetal cardiac catheterization.

RESULTS

Surviving banded fetuses (n = 13) had one of two phenotypes: compensatory left ventricular hypertrophy (n = 7) or noncompensatory left ventricular dilatation (n = 6) with hydrops and severe left ventricular dysfunction. All fetuses had elevated left ventricular end-diastolic pressures (mean, 21 mm Hg; range, 14 to 28 mm Hg), which correlated to the gradient across the ascending aorta (mean, 41 mm Hg; range, 28 to 73 mm Hg). In vivo echocardiography findings were incongruous with those at autopsy, and demonstrated preservation of left ventricular growth indices in all fetuses. Endocardial fibroelastosis and myocardial fibrosis were not observed in any banded fetus.

CONCLUSIONS

While early gestational obstruction to flow can compromise left ventricular function in the fetus, it does not retard normal growth. Similarly, an elevated left ventricular end-diastolic pressure is not sufficient to cause myocardial fibrosis or endocardial fibroelastosis in the fetus.

Aortic atresia or severe left ventricular outflow tract obstruction with ventricular septal defect: results of primary biventricular repair in neonates

BACKGROUND

Aortic atresia or severe aortic stenosis and left ventricular outflow tract obstruction is a frequent component of complex congenital heart disease. Aortic atresia or severe aortic stenosis and left ventricular outflow tract obstruction with two adequate ventricles is sometimes treated by Norwood palliation followed by late biventricular repair. We reviewed our experience with primary biventricular repair in this group of neonates.

METHODS

Retrospective review identified 17 neonates (10 males) with aortic atresia or severe left ventricular outflow tract obstruction with ventricular septal defect and an adequate left ventricle undergoing primary biventricular repair between 1986 and 2002. Mean age was 7.7 +/- 2.9 days, weight 3.3 +/- 0.7 kg, and body surface area 0.21 +/- 0.04 kg/m2. Associated anomalies included arch hypoplasia, 7 (41%); aortic atresia, 7 (41%); and coarctation, 5 (29%). Results are reported as mean +/- standard deviation.

RESULTS

Median follow-up was 6 years (range, 1 to 17.7 years). Three of the 17 (18%) died within 30 days. There were no deaths in this series since 1992. Nine patients (38.9%) required one reoperation, 7 of which were for conduit stenosis, 1 for left ventricular outflow tract obstruction, and 1 for residual ventricular septal defect with left ventricle-to-right atrium shunt. Freedom from death at 10 years was 82% by Kaplan-Meier estimate.

CONCLUSIONS

Excellent long-term survival can be achieved by primary biventricular repair as corroborated by our survival rate of 82%. Primary biventricular repair is an effective operation for aortic atresia and severe left ventricular outflow tract obstruction with adequate sized left ventricle that avoids interstage attrition associated with Norwood palliation and is our procedure of choice.

Early results of single-stage biventricular repair of severe aortic hypoplasia or atresia with ventricular septal defect and normal left ventricle

OBJECTIVE

Biventricular repair of aortic atresia (or severe aortic hypoplasia) is possible in the presence of a ventricular septal defect and normal left ventricle. We considered whether primary biventricular repair was a safe alternative in all cases, even in the presence of interrupted aortic arch.

METHODS

This was a retrospective analysis of patients who underwent primary biventricular repair consisting of a combination Norwood-type reconstruction of the aortic arch, baffle of the left ventricle to both semilunar roots, and conduit placement from the right ventricle to pulmonary arteries.

RESULTS

Between January 1995 and January 2005, a total of 21 patients underwent primary biventricular repair at a median age of 5 days and a median weight of 3.0 kg. Aortic atresia was present in 7 and aortic stenosis in 14; 6 had interrupted aortic arch. All patients with aortic stenosis had annular diameters 3 mm or smaller. Median circulatory arrest time was 55 minutes, aortic crossclamp time was 56 minutes, and total support time was 99 minutes. In-hospital survival was 100%. Postoperative echocardiography in 19 patients demonstrated no significant outflow tract obstruction. Total stay was a median of 17 days. At midterm follow-up, there has been 1 late death, and reoperation has been necessary in 10 cases.

CONCLUSION

Primary biventricular repair is a safe alternative to staged repair in all cases of aortic hypoplasia with ventricular septal defect and normal left ventricle.

Direct neonatal ventriculo-arterial connections (REV): early results and future implications

BACKGROUND

Is the time-honored supposition correct that insertion of a competent prosthetic conduit or homograft is necessary to achieve right ventricular (RV) to pulmonary artery continuity in neonates? A direct ventriculo-arterial connection, or réparation à l'étage ventriculaire (REV), has been successfully used to achieve RV to pulmonary artery continuity in neonates without mortality or major morbidity. Acute RV function is preserved even in the face of free pulmonary insufficiency, but scrupulous preservation of pulmonary artery patency (unobstructed pathway) must be achieved.

METHODS

We retrospectively reviewed the cases of 6 neonates who underwent direct ventriculo-arterial connection to achieve RV to pulmonary artery continuity during open heart procedures in the last 3 years.

RESULTS

The 6 neonates had a mean age of 12.3 days (range, 2 days to 6 weeks) and a mean weight of 3.2 kg (range, 2.7 to 3.6 kg) at operation. Two of them had a diagnosis of aortic atresia + ventricular septal defect and successfully achieved an in-series circulation. Two had pulmonary atresia + ventricular septal defect and 2, double-outlet right ventricle + transposition of the great arteries + ventricular septal defect + pulmonary atresia. Follow-up is a mean of 16 months (range, 6 to 22 months). Surgical reintervention was required in 3 neonates and resulted in excellent hemodynamics in 2 of them. In the other patient, who had bilateral long-segment branch pulmonary artery hypoplasia, stents were placed without hemodynamic benefit. All children are currently alive with preserved RV function even in the presence of free pulmonary insufficiency.

CONCLUSIONS

Although the creation of a direct ventriculo-arterial connection has routinely been used for children older than 1 year with satisfactory initial results, its application in neonate is very limited. Why have neonates been denied this viable alternative? Perhaps the answer involves legitimate concerns about the consequent free pulmonary insufficiency and the presumed acute RV diastolic dysfunction.