Anatomic features and surgical strategies in double-outlet right ventricle

Double outlet right ventricle - the 50% rule has always been about the conus

PURPOSE OF REVIEW

There has been much variability in the definition of double outlet right ventricle (DORV) spanning the last century. Historically, emphasis has been placed on the assignment of the great arteries to the right ventricle as a definition of DORV. In this review, we aim to underscore the importance of conal muscle, rather than rules surrounding assignment of great arteries to ventricles. We will be outlining the variability in patient anatomy that results from variations in conal muscle development in DORV, which may not fit perfectly into predefined constructs. This anatomic variability directly determines physiology and surgical repair options.

RECENT FINDINGS

There is a growing appreciation of the utility of cross-sectional imaging in complex DORV, and the generation of patient-specific 3D models with virtual reality simulations for surgical planning. These models improve the prediction of candidacy for biventricular repair and allow the mapping of complex baffle pathways preoperatively.

SUMMARY

DORV is not a disease entity in itself, but rather a vast spectrum of disorders associated with maldevelopment of conal muscle and often abnormal expansion of one the great vessels. Patient-specific 3D models will be crucial for improved surgical planning and patient outcomes.

Multicentre study on late outcomes of biventricular repair of double outlet right ventricle

OBJECTIVES

The goal of this retrospective multicentre study was to present late surgical outcomes of the treatment of children with double outlet right ventricle (DORV) coming from emerging countries.

METHODS

The Mécénat Chirurgie Cardiaque brings to France for surgery selected children with simple and complex congenital diseases, including DORV. The patients are operated on in 9 hospitals that specialize in paediatric cardiac surgery. Data are collected from the Mécénat Chirurgie Cardiaque comprehensive database, with a strict postoperative follow-up. The patients included only those who had biventricular repair of DORV with 2 viable ventricles. According to the classification of the Eleventh Revision of the International Classification of Diseases, DORV was defined as a congenital cardiovascular malformation in which both great arteries arise entirely or predominantly from the morphologically right ventricle.

RESULTS

From January 1996 to January 2022, a total of 81 consecutive DORV biventricular repair operations were performed. There were 6 subtypes of DORV divided into 2 groups: DORV-committed ventricular septal defect (VSD): DORV-VSD (n = 25), DORV-Fallot (n = 34), DORV-transposition of the great arteries (n = 5); and DORV-non-committed (nc) VSD: DORV-ncVSD-no pulmonary stenosis (PS) (n = 7), DORV-ncVSD-PS (n = 5) and DORV-atrioventricular septal defect (AVSD)-PS (n = 5). Four Fontan patients were excluded. Three patients were lost to follow-up (3.4%). The overall perioperative mortality was 7.4% ± 2.6%, 6/81 (95% confidence interval: 2.8%-15.4%) ranging from 0% in DORV-AVSD-PS to 14% for DORV-ncVSD-no PS. The overall 10-year survival was 86%. The early mortality of DORV-ncVSD at 5.9% ± 2.4% (1/17) was similar to that of DORV-committed VSD at 7.8% ± 2.7% (5/64) (P = 0.79). There was a trend towards an optimal outcome for the arterial switch operation and the DORV-AVSD-PS repair. VSD enlargement was significantly more frequent in DORV-ncVSD at 42% (5/12) (P = 0.001). There were low numbers in the complex groups. The number of Fontan cases was noticeably low. The aorta located entirely on the right ventricle represents the fundamental anomaly and the surgical challenge of DORV.

CONCLUSIONS

Overall survival at 10 years was 86%. This study shows a trend towards satisfactory early and late outcomes in BVR of simple DORV with committed VSD, compared to complex DORV with ncVSD.

Double outlet right ventricle in adults: Anatomic variability, surgical treatment, and late postoperative complications

Double outlet right ventricle (DORV) is a highly complex congenital heart disease (CHD) entity, gaining increasing interest due to the rapid progress of cardiac surgery. The number of patients operated for this congenital defect has been growing since 1980s and over following decades with active transitioning of this cohort into the adult medicine. However, the diversity of initial anomaly and performed interventions makes challenging the management of these patients. This is particularly important in the regions where specialized adult CHD cardiology still remains underdeveloped. In this review, we observe the basic principles of DORV nomenclature, main types of the operations and possible late complications. The article focuses on adult patients and offers illustrations from clinical practice.

Prognostic Value of CTA-Derived Left Ventricular Mass in Neonates with Congenital Heart Disease

For therapeutic decisions regarding uni- or biventricular surgical repair in congenital heart disease (CHD), left ventricular mass (LVM) is an important factor. The aim of this retrospective study was to determine the LVM of infants with CHD in thoracic computed tomography angiographies (CTAs) and to evaluate its usefulness as a prognostic parameter, with special attention paid to hypoplastic left heart (HLH) patients. Manual segmentation of the left ventricular endo- and epicardial volumes was performed in CTAs of 132 infants. LVMs were determined from these volumes and normalized to body surface area. LVMs of patients with different types of CHD were compared to each other using analyses of variances (ANOVA). An LVM cutoff for discrimination between uni- and biventricular repair was determined using receiver operating characteristics. Survival rates were calculated using Kaplan–Meier statistics. Patients with a clinical diagnosis of an HLH had significantly lower mean LVM (21.88 g/m²) compared to patients without applicable disease (50.22 g/m²; p < 0.0001) and compared to other CHDs, including persistent truncus arteriosus, left ventricular outflow tract obstruction, transposition of the great arteries, pulmonary artery stenosis or atresia, and double-outlet right ventricle (all, p < 0.05). The LVM cutoff for uni- vs. biventricular surgery was 33.9 g/m² (sensitivity: 82.3%; specificity: 73.7%; PPV: 94.9%). In a subanalysis of HLH patients, a sensitivity of 50.0%, specificity of 100%, PPV of 100%, and NPV of 83.3% was determined. Patient survival was not significantly different between the surgical approaches or between patients with LVM above or below the cutoff. LVM can be measured in chest CTA of newborns with CHD and can be used as a prognostic factor.

Mixed-reality hologram for diagnosis and surgical planning of double outlet of the right ventricle: a pilot study

AIM

To evaluate the mixed-reality (MR) hologram, a novel technology based on two-dimensional images, which simulates three-dimensional (3D) images and provides a dynamic and interactive alternative, for its usefulness in the diagnosis and surgical planning of double outlet of the right ventricle (DORV).

MATERIALS AND METHODS

Thirty-four patients who were suspected of DORV based on ultrasound findings underwent cardiac computed tomography angiography (CTA). The patients were assigned randomly to the MR holographic guidance (MRHG) group or the control group. For the patients in the MRHG group, the CTA images were converted into Standard Template Library (STL) files after segmentation, 3D reconstruction, colourisation, and transparentisation, and then exported for MR holographic visualisation. The CTA images of the patients in the control group were analysed using routine 3D reconstruction only. Diagnostic accuracy and surgical planning were compared between the two groups based on visualisation at surgery.

RESULTS

In the MRHG group, the 3D hologram observation was in concordance with the actual anatomical findings, and the DORV type was classified accurately in all patients. The diagnostic accuracy for the malformation was 95.5% in the MRHG group and 89.7% in the control group, but the difference was not significant (p=0.3). All the procedures were exactly the same as planned based on the 3D MR holographic model. The surgical planning time was shorter for the MRHG group (51.65 ± 11.11 min) than that for the control group (65.71 ± 18.07 min, p<0.05).

CONCLUSION

MR 3D holograms may provide a clear and deeper anatomical perception of DORV and improve surgical planning.

Conversion of prior univentricular repairs to septated circulation: Case selection, challenges, and outcomes

Objectives

Complex congenital heart defects that present earlier in life are sometimes channelled in the single ventricle pathway, because of anatomical or logistic challenges involved in biventricular correction. Given the long-term functional and survival advantage, and with the surgeons' improved understanding of the cardiac anatomy, we have consciously explored the feasibility of a biventricular repair in these patients when they presented later for Fontan completion. We present a single institution's 10-year experience in achieving biventricular septation of prior univentricular repairs, the technical and physiological challenges and the surgical outcomes.

Methods

Between June 2010 and December 2019, 246 patients were channelized in the single ventricle pathway, of which 32 patients were identified as potential biventricular candidates at the time of evaluation for Fontan palliation, considering their anatomic feasibility. The surgical technique involves routing of the left ventricle to the aorta across the ventricular septal defect, ensuring an adequate sized right ventricular cavity, establishing right ventricle-pulmonary artery continuity and taking down the Glenn shunt with rerouting of the superior vena cava to the right atrium. This is a retrospective study where we reviewed the unique physiological and surgical characteristics of this subset of patients and analysed their surgical outcomes and complications.

Results

Biventricular conversion was achieved in all cases except in 3 patients, who had the Glenn shunt retained leading to a one and a half ventricle repair. The average age of the patients was 4.9 years of whom 18 were male. The average cardiopulmonary bypass time was 371 min with an average cross clamp time of 162 min. There was one mortality in a patient with corrected transposition of great arteries (c-TGA) with extensive arterio-venous malformations (AVMs). At a median follow-up of 60 months, all patients remained symptom free except two with NYHA II symptoms, one being treated for branch pulmonary artery stenosis with balloon dilatation and the other with multiple AVMs who needed coil closure. One patient with branch pulmonary artery (PA) stenosis required balloon dilatation and stent placement.

Conclusion

The possibility of achieving the surgical goal in this unique subset of patients evolves with the progressive experience of the congenital heart surgeon. Case selection is a crucial aspect in achieving the desired outcome, and this 'borderline' substrate is often recognized at the time of evaluation for the Fontan completion. A comprehensive preoperative imaging and planning helps in achieving the surgical septation and reconnection to achieve the desired physiological circulation. Though technically challenging, the surgery has excellent short- and mid-term outcomes as evidenced by our 10-year experience.

[Cyanosis in a calf with a double outlet right ventricle]

A 4-day-old female Holstein Friesian calf was presented for evaluation of cyanosis and dyspnea. On auscultation, severe bronchovesicular sounds and a systolic heart murmur of grade IV/VI above the tricuspid valve were found. On echocardiography, a marked dextroposition of the aorta (> 50% originating from the right ventricle), leading to both great arteries arising from the right ventricle - a so-called double-outlet right ventricle - was detected. Two ventricular septal defects were present, one in the perimembranous, subpulmonary region, the other non-committed in the muscular region. The subpulmonary ventricular septal defect was responsible for the shunting of unoxygenated blood into the aorta. Additionally, an aneurysma-like atrial septal defect (type secundum) and a large patent ductus arteriosus were visualized. The main pulmonary artery was severely enlarged without the presence of a stenotic defect. The findings could be verified by angiography. Additionally, a diffuse hypoplastic ascending aorta was visualized. Necropsy confirmed the echocardiographic and angiographic findings.

Acute and midterm results following perventricular device closure of muscular ventricular septal defects: A multicenter PICES investigation

OBJECTIVES

To describe acute and mid-term results of hybrid perventricular device closure of muscular ventricular septal defects (mVSDs).

BACKGROUND

Perventricular device closure of mVSDs can mitigate technical limitations of percutaneous closure and need for cardiopulmonary bypass or ventriculotomy with a surgical approach.

METHODS

This is a multicenter retrospective cohort study of patients undergoing hybrid perventricular mVSD device closure from 1/2004 to 1/2014. Procedural details, adverse events, outcomes, and follow-up data were collected. Patients were divided into two groups: (1) simple (mVSD closure alone) and (2) complex (mVSD closure with concomitant cardiac surgery).

RESULTS

Forty-seven patients (60% female) underwent perventricular mVSD device closure at a median age of 5.2 months (IQR 1.8-8.9) and weight of 5.1 kg (IQR 4.0-6.9). Procedural success was 91% [100% (n = 22) simple and 84% (n = 21/25) complex]. Adverse events occurred in 19% (9/47) [9% (2/22) simple and 28% (7/25) complex]. Hospital length of stay (LOS) was shorter in the simple vs. complex group (4 vs. 14 days, P < 0.01). At mid-term follow-up of 19.2 months (IQR 2.3-43) 90% of pts had complete mVSD closure; none developed late heart block, increased atrioventricular (AV) valve insufficiency or ventricular dysfunction.

CONCLUSIONS

Perventricular device closure of simple mVSD was associated with a high rate of procedural success, few adverse events, and short hospital LOS. Procedural adverse events were associated with the presence of concomitant complex surgery. Residual mVSD, AV valve insufficiency, or ventricular dysfunction were uncommon at mid-term follow-up. © 2017 Wiley Periodicals, Inc.

Three-Dimensional Reconstruction of Intracardiac Anatomy Using CTA and Surgical Planning for Double Outlet Right Ventricle: Early Experience at a Tertiary Care Congenital Heart Center

BACKGROUND

Although transthoracic echocardiography (TTE) routinely establishes the diagnosis of double outlet right ventricle (DORV), it can be suboptimal for depicting exact ventricular septal defect (VSD) position, especially with respect to the outflow tracts. Advanced imaging with computed tomography angiography (CTA) can help visualize structures and relationships not easily seen by echo. Using computer-aided design, we have the ability to create three-dimensional (3D) models of the intracardiac anatomy, which can be helpful for better depicting the overall anatomy to assist surgical planning.

METHODS

Patients with a diagnosis of DORV were retrospectively reviewed at our institution from October 2013 to April 2015. Patients who preoperatively underwent both TTE and CTA with 3D reconstruction of the intracardiac anatomy were included. Computed tomography angiography findings with 3D intracardiac model creation were compared to the surgical findings.

RESULTS

Twenty-five patients underwent surgical repair of DORV during the study period. Five patients had CTA with 3D reconstruction, in addition to the standard TTE images, and were included in the study. In all five cases, CTA with 3D reconstruction of the intracardiac anatomy accurately depicted the VSD position relative to important adjacent structures, including the outflow tracts.

CONCLUSION

Three-dimensional reconstruction of the intracardiac anatomy using CTA data can provide accurate data for presurgical planning of DORV repair and has the potential for being especially useful in patients for whom intracardiac anatomy and VSD position cannot be well seen by TTE. A larger prospective analysis is warranted to help validate this approach.

Impact of anatomic characteristics and initial biventricular surgical strategy on outcomes in various forms of double-outlet right ventricle

OBJECTIVES

Surgical management of various forms of double-outlet right ventricle uses a variety of approaches depending on the underlying anatomic form. In this study, we sought to determine the risk factors of mortality and reoperation in those with double-outlet right ventricle undergoing biventricular repair, according to anatomic characteristics and initial surgical strategy.

METHODS

Between 1992 and 2013, 433 patients were included in the study. Double-outlet right ventricle was classified as double-outlet right ventricle with subaortic ventricular septal defect associated with subpulmonary obstruction in 33% of patients (n = 141), with subaortic ventricular septal defect without subpulmonary obstruction in 30% of patients (n = 130), with subpulmonary ventricular septal defect in 32% of patients (n = 139), and with noncommitted ventricular septal defect in 5% of patients (n = 23). Three types of repairs were performed: (1) intraventricular baffle repair, n = 149 (34%); (2) intraventricular baffle repair with right ventricular outflow tract reconstruction, n = 163 (38%); and (3) intraventricular baffle repair with arterial switch operation, n = 121 (28%).

RESULTS

Thirty-day overall mortality was 7.4%. Early reoperation was needed in 6% of the cases. Early mortality was higher in the intraventricular baffle repair with arterial switch operation group (P = .01). Survival at 10 years was 86.2%, and freedom from reoperation at 10 years was 61.4%. At last follow-up (median, 5.7 years; 95% confidence interval, 4.5-6.6), mortality and reoperation rates were similar in the different surgical strategy groups. Late reoperation and late mortality were significantly higher in the double-outlet right ventricle with noncommitted ventricular septal defect group (P < .01). In multivariate analyses, risk factors for reoperation were concomitant surgical procedures (P = .03) and duration of cardiopulmonary bypass (P < .01). Risk factors for mortality were restrictive ventricular septal defect (P = .01), mitral cleft (P < .01), and associated coronary artery anomalies (P = .01).

CONCLUSIONS

Those with the anatomic type of double-outlet right ventricle with noncommitted ventricular septal defect were at higher risk for reoperation and mortality. Intraventricular baffle repair with arterial switch operation was the surgical strategy in patients at higher risk of early death. Initial surgical strategy did not influence the late outcomes.

Biventricular repair in heterotaxy patients

BACKGROUND

Heterotaxy patients' hearts may or may not be suitable for biventricular repair depending on anatomy. Even in the subset that are amenable to surgical septation, cardiac anatomy may present multiple difficulties in achieving a satisfactory repair. However, it is also well known that heterotaxy patients are not ideal candidates for univentricular repair.

METHODS

From 2007 until 2012, a total of 20 patients (11 male) with heterotaxy syndrome underwent biventricular repair (left atrial isomerism: 10 and right atrial isomerism: 10) in our center. Their median age at surgery was 40 (range: 3-108) months. Ten patients had dextrocardia. Eleven patients presented with bilateral superior vena cava, three with inferior vena cava (IVC) draining into left atrium, and six with IVC interruption with azygos or hemiazygos continuation. Anomalous pulmonary venous drainage was present in eight patients. One had a common atrium. Atrioventricular septal defect (AVSD) occurred in nine (complete AVSD in seven) patients. Eight patients had double outlet right ventricle (DORV), one had d-transposition of great arteries (d-TGA), and two had congenitally corrected transposition of the great arteries (CC-TGA). Prior palliative procedures included pulmonary artery banding in three patients and left modified Blalock-Taussig shunt in one patient. Complex intra-atrial baffle constructions were required in all patients to direct pulmonary and systemic venous inflow to the appropriate ventricle. Complete AVSDs were corrected using two-patch technique. Intraventricular tunnel repair was done for DORV. Combined atrial and arterial switch was required to rectify abnormal connections in a child with congenitally corrected transposition with normal pulmonary valve, while a Rastelli + Senning was needed in two children with CC-TGA with pulmonary atresia (n = 1) and double outlet of the right ventricle (n = 1).

RESULTS

Major early postoperative complications included intestinal gangrene in four patients for which they underwent bowel resection. Two of these patients could not be salvaged. One patient required coiling of aortopulmonary collateral for early postoperative pulmonary hemorrhage. Two patients needed a tracheostomy for prolonged mechanical ventilatory support. Five patients had a pacemaker implanted for complete heart block. There were no instances of atrial baffle stenosis. Median follow-up was 27 (range: 2-46) months. There was one late death secondary to pneumonia.

CONCLUSIONS

Satisfactory survival outcomes can be achieved in heterotaxy patients who undergo hemodynamically acceptable biventricular repair. Borderline ventricular hypoplasia and trivial atrioventricular valve regurgitation should not be considered as discouraging factors in anatomically suitable heterotaxy patients as it is possible to adopt a two-stage repair in such patients to achieve biventricular repair at a later stage. Anticipating a higher incidence of conduction problems and gut malrotation preemptively can help reduce the morbidity.

Longer-term outcome of perventricular device closure of muscular ventricular septal defects in children

OBJECTIVE

To describe the longer-term clinical experience and follow-up with perventricular device closure of ventricular septal defects (VSD) in children.

METHODS

Between January 2005 and December 2013, muscular ventricular septal defect closure with the Amplatzer Muscular VSD Occluder was undertaken using a hybrid perventricular approach. Data including demographic, echocardiographic parameter, and clinical outcome were reviewed retrospectively.

RESULTS

Median age at the time of procedure was 8.9 months (range 1.9-31.0 months) and median weight was 6.6 kg (range 4.5-12.9 kg). All had a moderate to large muscular VSD, three had more than one VSD, four had previous coarctation repair, and five had previous pulmonary artery (PA) banding. A single Amplatzer muscular occluder (range 8-18 mm) was deployed in each patient without cardiopulmonary bypass under echocardiographic guidance. Two of ten patients subsequently required a short period of cardiopulmonary bypass for reconstruction of PA after de-banding and closure of atrial septal defect in one. Occluder removal was necessary in one patient due to entrapment of the tricuspid valve and progressive tricuspid regurgitation. This patient underwent surgical repair with a good result and no device-related valve damage. In the remaining nine patients, no severe complications such as device embolization, arrhythmia, or significant valve regurgitation were noted in the post-operative period or follow-up. At a median time of 6.5 years (range 0.9-8.4 years) post device implantation, complete closure was achieved in five patients and four had small residual leaks, which were not hemodynamically significant.

CONCLUSION

Perventricular muscular VSD closure is effective in small children with suitable muscular defects and may avoid the morbidity associated with cardiopulmonary bypass and conventional surgical repair. There have been no late complications with this approach.

Surgical outcomes of 380 patients with double outlet right ventricle who underwent biventricular repair

OBJECTIVES

The study objective was to report the outcomes of biventricular repair in patients with double outlet right ventricle.

METHODS

Patients with double outlet right ventricle who underwent biventricular repair at Fuwai Hospital from January 2005 to December 2012 were included. Patients were excluded if double outlet right ventricle was combined with atrioventricular septal defect, heterotaxy syndrome, atrioventricular discordance, or univentricular physiology.

RESULTS

A total of 380 consecutive patients with a mean age of 1.9 ± 2.1 years (range, 1 month to 6 years) were included. Varied types of biventricular repair were customized individually. Follow-up was 90.4% complete, and the mean follow-up time was 3.4 ± 3.9 years. There were 17 (4.5%) early deaths and 7 (2.1%) late deaths. Preoperative pulmonary hypertension was the only risk factor for early mortality. Postoperative significant left ventricular outflow tract obstruction was present in 9 survivors. Patients with noncommitted ventricular septal defect had a longer crossclamp time, longer cardiopulmonary bypass time, and higher incidence of postdischarge left ventricular outflow tract obstruction. There were 4 reoperations, all of which were caused by subaortic left ventricular outflow tract obstruction. All of the pressure gradients were decreased to less than 20 mm Hg after the modified Konno procedure with an uneventful postoperative course.

CONCLUSIONS

Optimal results of varied types of biventricular repair for double outlet right ventricle have been acquired. Although noncommitted ventricular septal defect is technically difficult, the outcomes of patients are favorable. Late-onset left ventricular outflow tract obstruction is the main reason for reoperation but can be successfully relieved by the modified Konno procedure.

Two-ventricle repair for complex congenital heart defects palliated towards single-ventricle repair

OBJECTIVES

Complex congenital heart defects that present earlier in life are sometimes channelled towards single-ventricle repair, because of anatomical or logistic challenges involved in two-ventricle correction. Given the long-term functional and survival advantage, we have been consciously exploring the feasibility of a biventricular repair in these patients when they present later for Fontan completion.

METHODS

Since June 2009, 71 patients were referred for staged completion of the Fontan procedure. Following detailed evaluation that included three-dimensional echocardiography and magnetic resonance imaging, 10 patients (Group 1-median age 6 years) were identified and later underwent complex biventricular repair with takedown of Glenn shunt, while completion of extracardiac Fontan repair was done in 61 patients (Group 2-median age 7 years).

RESULTS

Two-ventricle repair was accomplished in all the 10 Group 1 patients. One patient developed complete heart block requiring permanent pacemaker insertion. Late patch dehiscence occurred in another (awaiting repair). At a median follow-up of 15 months, there was no mortality among the Group 1 patients and all except for 1 patient were symptom free. There were 2 early deaths (3.3%) in the Group 2 patients.

CONCLUSIONS

Two-ventricular repair, although surgically challenging, should be considered in all patients with two functional ventricles who come for Fontan completion. Comprehensive preoperative imaging and meticulous planning helps in identifying suitable candidates.

The role of the Fontan operation in the treatment of congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries (ccTGA) is a complex cardiac anomaly with an unfavorable natural history. Surgical treatment has been available for over 50 years. Initial procedures used for ccTGA did not correct atrio-ventricular discordance, leaving the right ventricle in systemic position. In the past two decades anatomic repair has been considered to be a better option. Many cases subjected to anatomic repairs would also be suitable for the Fontan strategy, which probably has a lower initial risk. The rationale for use of the Fontan operation in management of congenitally corrected transposition is discussed in this review, with comparisons to other strategies.

Novel method for delivering the Amplatzer muscular VSD occluder in a patient with double outlet right ventricle after bidirectional Glenn procedure and pulmonary artery band

We report the first use of bilateral femoral venovenous rail creation for the delivery of an Amplatzer Muscular Ventricular Septal Defect Occluder in a patient with a large mid-to-apical muscular ventricular septal defect before Rastelli operation. The presence of a right-sided bidirectional Glenn shunt, a banded main pulmonary artery, and double outlet right ventricle anatomy precluded the use of standard delivery techniques. The patient underwent successful transcatheter device placement followed by Rastelli operation on the following day.

Determinants of repair type, reintervention, and mortality in 393 children with double-outlet right ventricle

OBJECTIVE

We sought to define the prevalence of definitive end-states and their determinants in children with double-outlet right ventricle.

METHODS

We performed a clinical record review of 393 children with double-outlet right ventricle presenting to our institution from 1980 to 2000.

RESULTS

Double-outlet right ventricle classification was as follows: subaortic ventricular septal defect with or without pulmonary stenosis in 47%, subpulmonic ventricular septal defect in 23%, noncommitted ventricular septal defect in 26%, and doubly committed ventricular septal defect in 4%. Hypoplastic ventricles were present in 39%, pulmonary stenosis was present in 65%, and aortic arch obstruction was present in 24%. Biventricular repair was performed in 194 patients (55%) at a median age of 10 months (range: birth to 14.0 years), and the Fontan operation (n = 182; 23%) was performed at a median age of 3.7 years (range: 6 months to 14.9 years). Results improved over time (P < .001). Factors discriminating among end-states included younger patient age at presentation (P < .001), lower weight (P < .001), and adequacy of left-sided heart structures, especially the size of the left ventricle (P < .001), aortic arch (P < .001), and mitral valve (P = .004). For complex double-outlet right ventricle, Rastelli-type repair increased early reintervention risk (P = .04) and late post-repair mortality (P = .02), whereas the arterial switch operation increased early post-repair mortality (P = .02) with a benefit of improved late post-repair survival.

CONCLUSIONS

Biventricular repair, especially Rastelli-type reconstruction, is associated with higher late mortality and reintervention than is Fontan repair. The wisdom of extending biventricular repair to borderline anatomic candidates with hypoplastic left-sided structures or a nonsubaortic ventricular septal defect is questionable.

Surgical repair of multiple muscular ventricular septal defects: the role of re-endocardialization strategy

OBJECTIVE

Surgical repair of multiple muscular ventricular septal defects (Swiss cheese septum) is associated with important morbidity and mortality. We sought to examine factors associated with permanent heart block, early mortality, and time-related survival. Additionally, we evaluated a new approach, transatrial re-endocardialization of interventricular septum, to mitigate risk.

METHODS

One hundred sixteen patients underwent surgery for multiple muscular ventricular septal defects (1982-2005), of whom 64 (55%) had associated cardiac anomalies. Twenty-seven consecutive patients (median age 0.54 years, range 15 days-7.2 years) underwent transatrial re-endocardialization (2002-2005). Forty-four percent had Swiss cheese septum (>4 defects). Multivariable regression analysis determined risk factors for pacemaker and survival.

RESULTS

Operative mortality for the entire cohort was 9%. Risk factors for death were double-outlet right ventricle (odds ratio 44.7, P = .003), ventriculotomy (odds ratio 6.4, P = .03), and fewer multiple muscular ventricular septal defects repaired (odds ratio 4.7/defect, P = .04). Era mortalities differed: 16% for 1982 through 1990, 13% for 1990 through 1998, and 0% for 1999 through 2005, P = .006). Fourteen patients (12%) required a pacemaker. Time-related survivals at 1 and 10 years were 90% +/- 3% and 82% +/- 5%. Risk factors for death were double-outlet right ventricle (hazard ratio 8.3, P = .02) and longer bypass (hazard ratio 1.02/min, P = .02). In 27 re-endocardialization patients, a combined closure strategy to close 184 defects were applied: transatrial re-endocardialization (median 5, range 2-21), patch (median 1, range 0-4), and device (range 0-1). Post-repair ventricular function was good in 25 of 27 patients. The median number of residual defects was 1.5 (range 0-3), and median residual jet width on color Doppler was 2.3 mm (range 0-4.2 mm). One child required a pacemaker. There were no early or late deaths.

CONCLUSIONS

Outcome of surgical repair of multiple muscular ventricular septal defects (Swiss cheese septum) has improved. Transatrial re-endocardialization strategy enables early complete or nearly complete obliteration of multiple muscular ventricular septal defects with minimal residual lesions (shunt, ventricular dysfunction). Long cardiopulmonary bypass duration is well tolerated. The incidence of permanent heart block has improved. Early echocardiographic and clinical outcomes are promising.

Double outlet right ventricle: opinions regarding management

In the current era of superb surgical results for congenital heart disease, several management options are available for patients born with double outlet right ventricle (DORV). The surgical repair of DORV is tailored to address the variety of abnormalities associated with this lesion. The treatment strategies are dependent upon the anatomy and relationship of the ventricular septal defect (VSD) and the great arteries. For patients with subaortic or doubly committed VSDs, without right ventricular outflow tract obstruction, the usual repair is an intraventricular tunnel from the VSD to the aorta. If right ventricular outflow tract obstruction exists, then augmentation of the right ventricular outflow tract or conduit placement from the right ventricle to the pulmonary artery is necessary. For the "Taussig-Bing anomaly" (subpulmonary VSD) an arterial switch operation is indicated with tunneling of the VSD to the neoaorta. For patients with a remote VSD, complex atrioventricular valve abnormalities, or unbalanced ventricles, a staged palliative approach is warranted. This approach will result in the patient having "single ventricle" physiology, and "Fontan anatomy" after the staging surgeries. Outcomes are determined by the surgery performed. Patients who require conduit placement from right ventricle to pulmonary artery will need subsequent surgery for replacement of the conduit. Complex intraventricular tunnels are at risk for developing subaortic obstruction. Patients who had arterial switch operations have thus far had excellent results. However, these patients may be at risk for development of neoaortic valve regurgitation requiring subsequent reoperation. Complex biventricular intracardiac repairs have been associated with a higher risk of reoperation. In the past 10 to 15 years, patients undergoing Fontan operations have had improved early and late survival. However, long-term problems after the Fontan operation include arrhythmia and development of protein-losing enteropathy.

Hybrid pediatric cardiac surgery

Minimally invasive strategies can be expanded by combining standard surgical and interventional techniques. We performed a longitudinal prospective study of all pediatric patients who have undergone hybrid cardiac surgery at the University of Chicago Children's Hospital. Hybrid cardiac surgery was defined as combined catheter-based and surgical interventions in either one setting or in a planned sequential fashion within 24 hours. Between June 2000 and June 2003, 25 patients were treated with hybrid approaches. Seventeen patients with muscular ventricular septal defects (mVSDs) (mean age, 4 months; range, 2 weeks-4 years) underwent either sequential Amplatzer device closure in the catheterization laboratory followed by surgical completion (group 1A, n = 9) or one-stage intraoperative off-pump device closure (group IB, n = 8) with subsequent repair of any concomitant heart lesions. Eight patients with branch pulmonary artery (PA) stenoses (group 2) underwent intraoperative PA stenting or stent balloon dilatation along with concomitant surgical procedures. All patients survived hospitalization. Complications from the hybrid approach were mostly confined to groups 1A and 2. At a mean follow-up of 18 months, 2 group 1A patients died suddenly several months after discharge. All other patients are doing well. Hybrid pediatric cardiac surgery performed in tandem by surgeons and cardiologists is safe and effective in reducing or eliminating cardiopulmonary bypass. Patients with mVSDs who are small, have poor vascular access, or have concomitant cardiac lesions are currently treated in one setting with the perventricular approach.

Multicenter experience with perventricular device closure of muscular ventricular septal defects

Hybrid procedures are becoming increasingly important, especially in the management of congenital heart lesions for which there are no ideal surgical or interventional options. This report describes a multicenter experience with perventricular muscular venticular septal defect (VSD) device closure. Three groups of patients (n = 12) were identified: infants with isolated muscular VSDs (n = 2), neonates with aortic coarctation and muscular VSDs (n = 3) or patients with muscular VSDs and other complex cardiac lesions (n = 2), and patients with muscular VSDs and pulmonary artery bands (n = 5). Via a sternotomy or a subxyphoid approach, the right ventricle (RV) free wall was punctured under transesophageal echocardiography guidance. A guidewire was introduced across the largest defect. A short delivery sheath was positioned in the left ventricle cavity. An Amplatzer muscular VSD occluding device was deployed across the VSD. Cardiopulmonary bypass was needed only for repair of concomitant lesions, such as double-outlet right ventricle, aortic coarctation, or pulmonary artery band removal. No complications were encountered using this technique. Discharge echocardiograms showed either mild or no significant shunting across the ventricular septum. At a median follow-up of 12 months, all patients were asymptomatic and 2 patients had mild residual ventricular level shunts. Perventricular closure of muscular VSDs is safe and effective for a variety of patients with muscular VSDs.

Hybrid procedures in pediatric cardiac surgery

Hybrid pediatric cardiac surgery is an emerging field that combines skills and techniques used by pediatric cardiac surgeons and interventional pediatric cardiologists. This article describes the emerging indications and techniques in hybrid pediatric cardiac surgery and discusses potential future applications. It focuses on peratrial and perventricular septal defect closure, intraoperative stenting, hybrid stage I palliation for hypoplastic left heart syndrome, and percutaneous valve implantation.

Selective timing for the arterial switch operation

BACKGROUND

To determine outcomes for the arterial switch operation individualized according to the underlying anatomy and clinical status.

METHODS

A retrospective review of a consecutive series of infants less than 90 days of age who underwent the arterial switch operation at a single institution.

RESULTS

From July 1993-April 2001, 117 infants underwent an arterial switch operation before 90 days of age. Seventy-five patients (64%) had transposition of the great arteries with intact ventricular septum with the aim of operation before 14 days of age; however, 8 of these patients had delayed presentation (range 15-46 days). Thirty-five patients (30%) had transposition with a ventricular septal defect (30 patients) or double outlet right ventricle (5 patients) and normal arch anatomy and were repaired within the first 90 days of life depending on the severity of heart failure at a median of 12 days of age (range 3-83 days). Seven patients (6%) had associated aortic coarctation (5 patients) or interrupted aortic arch (2 patients). One patient died during hospitalization (0.85% hospital mortality) and one patient died from noncardiac causes during a median follow-up of 35 months (1.7% total mortality). Four patients required intervention during follow-up (3.4%) for new aortic coarctation (2 patients), supravalvar pulmonic stenosis (1 patient), or right hemi-diaphragm paralysis (1 patient).

CONCLUSIONS

Individualized timing for the arterial switch operation within the first ninety days of life produces excellent survival rates for all types of transposition physiology with the expectation of a satisfactory course during follow-up.

Perventricular device closure of muscular ventricular septal defects on the beating heart: technique and results

OBJECTIVE

Both surgical management and percutaneous device closure of muscular ventricular septal defects have drawbacks and limitations. This report describes our initial experience with intraoperative device closure of muscular ventricular septal defects without cardiopulmonary bypass in 6 consecutive patients.

METHODS

A median sternotomy or a subxiphoid minimally invasive incision was performed. Under continuous transesophageal echocardiographic guidance, the right ventricle free wall was punctured, and a wire was introduced across the largest defect. The Amplatzer (AGA Medical Corporation, Golden Valley, Minn) muscular ventricular septal defect occluding device (a self-expandable double-disk device) was used. An introducer sheath was fed over the wire, with the sheath tip positioned in the left ventricle cavity. The device was then advanced inside the sheath and deployed by retracting the sheath. Associated cardiac lesions, if any, can then be repaired during cardiopulmonary bypass. A similar technique can also be applied for periatrial closure of complex atrial septal defects.

RESULTS

The initial 6 patients are presented. Cardiopulmonary bypass was not needed in any patient for placement of the device and needed in 4 patients for repair of concomitant malformations only (double-outlet right ventricle, aortic arch hypoplasia, pulmonary artery band removal). No complications from using this technique occurred. Discharge echocardiograms showed no significant shunting across the ventricular septum.

CONCLUSIONS

Perventricular closure of multiple muscular ventricular septal defects is safe and effective. We believe that this could become the treatment of choice for any infant with muscular ventricular septal defects or any child with muscular ventricular septal defect and associated cardiac defects.

Cardiovascular malformations in infants of diabetic mothers

OBJECTIVE

To compare the prevalence at live birth and the spectrum of cardiovascular malformations in infants born to diabetic mothers with pre-existing diabetes with that in infants of non-diabetic mothers.

DESIGN

Prospective study of all live births in the resident population of one health region, with recording of details of the outcome of all pregnancies of women with pre-existing diabetes and of all live born babies with cardiovascular malformations.

RESULTS

In the six years 1995-2000 there were 192 618 live births in the study population. Cardiovascular malformations were confirmed in 22 of 609 (3.6%) babies with diabetic mothers and in 1417 of 192 009 (0.74%) babies with non-diabetic mothers. The odds ratio for a cardiovascular malformation with maternal diabetes was 5.0 (95% confidence interval 3.3 to 7.8). Combination of these results with previous reports and comparison with the spectrum of cardiovascular malformations in infants of non-diabetic mothers shows a greater than threefold excess of transposition of the great arteries, truncus arteriosus, and tricuspid atresia.

CONCLUSIONS

Pre-existing maternal diabetes is associated with a fivefold increase in risk of cardiovascular malformations. Transposition of the great arteries, truncus arteriosus, and tricuspid atresia are overrepresented to produce a substantial excess of these malformations.

Management and outcome of patients with abnormal ventriculo-arterial connections and mitral valve cleft

BACKGROUND

In patients with abnormal ventriculo-arterial connections, a mitral valve cleft different from an atrioventricular canal is occasionally associated. It may cause outflow obstruction, mitral regurgitation, and complicate biventricular repair.

METHODS

A retrospective review identified 21 patients operated upon with mitral valve cleft, abnormal ventriculo-arterial connections, and two well-developed ventricles. Eight patients had a ventricular outflow obstruction due to the mitral valve, whereas 2 had more than mild mitral regurgitation. One patient required initial mitral valve surgery. Eleven patients underwent biventricular repair, associated with mitral valve repair in 2 cases: arterial switch operation (n = 4), Senning operation (n = 3) associated with an arterial switch operation in one case, intraventricular repair (n = 3), and Rastelli-type extracardiac conduit repair (n = 1). Single-ventricle palliation was preferred in 10 patients with major mitral valve straddling (n = 5), outflow tract obstruction (n = 2), and noncommitted or multiple VSDs (n = 3).

RESULTS

There were three hospital deaths, two of which occurred after biventricular repair and one after an early reoperation after a bidirectional cavopulmonary anastomosis. Postoperatively after biventricular repair, 1 patient required permanent pacemaker implantation and 3 patients were reoperated on for subaortic stenosis (n = 1) and mitral regurgitation (n = 2), with one late death. By multivariate analysis, patients with a double-outlet right ventricle were at greater risk of death (p = 0.04). After a mean follow-up period of 60.7 months (+/- 68.6 months), 16 patients are in New York Heart Association (NYHA) class I. One patient with a moderate mitral regurgitation on Doppler study is in NYHA class II.

CONCLUSIONS

The surgical management remains controversial in patients with abnormal ventriculo-arterial connections and mitral valve cleft. Biventricular repair may not always be feasible, especially in cases of complex intracardiac anatomy associated with mitral valve straddling. Single-ventricle palliation can be achieved in these patients, although it is unknown whether the long-term results are as good as those obtained with biventricular repair.

The role of the Fontan procedure in the surgical treatment of congenital heart malformations with double-outlet right ventricle

The Fontan procedure in one of its many modifications is applicable to the surgical treatment of those patients with double-outlet right ventricle who are not amenable to bi-ventricular correction. Included in this group are patients with significant hypoplasia of one of the ventricles, patients with distant (non-committed) ventricular septal defect, patients with significant straddling of the atrioventricular valves, patients with abnormal atrioventricular connections (such as absence of one of the valves), or common atrioventricular valve connection. The presence of complex associated lesions such as those seen in the heterotaxia syndromes may, by virtue of the surgical risk of attempts at bi-ventricular repair, make the Fontan approach a suitable option for these patients. The presence of a subaortic conus and the potential for subaortic obstruction, a frequent findings in patients with double outlet right ventricle, plays an important role in the preparation and conduct of the Fontan operation. Copyright 2000 by W.B. Saunders Company

Surgical management of double-outlet right ventricle with subaortic ventricular septal defect

Double-outlet right ventricle (DORV) and subaortic ventricular septal defect (VSD) is defined anatomically as a defect where the entire pulmonary trunk and at least half of the aorta arises from the right ventricle (RV) and the VSD is most closely aligned with the aorta. The surgical management of DORV and subaortic VSD usually results in a 2 ventricle repair where the left ventricular outflow is diverted via the VSD to the aorta. Pulmonary and/or subpulmonary obstruction is found in a large portion of these patients and requires relief at the time of repair. Resection of subpulmonary muscular obstruction with right ventricular outflow augmentation with a patch is required in most to eliminate the obstruction. Important anatomic features to consider in constructing the left ventricular outflow tunnel include the prominence of the conal septum, tricuspid valve attachments to conal septum, and the distance between the pulmonary and tricuspid valves. Operative mortality is low and long-term complications and need for reoperation is uncommon. This report describes the surgically relevant anatomic features and operative techniques. Copyright 2000 by W.B. Saunders Company

Double-outlet right ventricle: Pathology and angiocardiography

Double-outlet right ventricle is but one form of abnormal ventriculoarterial connection. The definition that more than half of each great artery originates above the morphologically right ventricle is arbitrary. As pointed out by Lecompte, those features that should be defined in hearts with the ventriculoarterial connection of double-outlet right ventricle (and indeed other forms of abnormal ventriculoarterial connection) include the nature of the infundibular septum, ventriculoinfundibular fold, trabeculoseptomargin-alis, attachments of infundibular septum to anterior or posterior limb of trabeculoseptomargin-alis, the size and position of the ventricular septal defect, the spatial relation of great artery(s) to the ventricular septal defect, the spatial relationship between the great, and the distance between the tricuspid and pulmonary valves and the semilunar valves. Copyright 2000 by W.B. Saunders Company

Spin echo MRI in the evaluation of hearts with a double outlet right ventricle: usefulness and limitations

The surgical approach to a double outlet right ventricle (DORV) is dependent on the spatial relationship of the semilunar valves, outflow tracts and ventricular septal defect (VSD). The purpose of the study was to assess the value of MRI for the evaluation of cardiovascular anatomy in patients before and after surgery for DORV. Spin echo MRI was performed in 12 patients with DORV (eight preoperative and four postoperative patients). Thin-section MRI was performed in three orthogonal planes and selected angulated views were obtained. Conventional imaging by color Doppler echocardiography and cine-angiocardiography and surgical findings, when present, served as the reference standards. The results found that the spatial relationship between semilunar valves and VSD was accurately assessed by MRI in eight out of eight preoperative patients. In the four postoperative cases MRI depicted the morphology of both outflow tracts and provided adequate information on their patency. Of the eight preoperative patients, five have undergone corrective surgery and the MRI findings were confirmed. MRI provided additional information to conventional imaging preoperatively in three cases in which the VSD opened into the outlet portion of the DORV, without there being a direct relation to a semilunar valve. In two preoperative cases in which the VSD was directly committed to the aorta, conventional imaging was conclusive. MRI was unable to depict aberrant chordae tendineae in four out of four cases. We conclude that MRI provides accurate additional anatomic information in patients with DORV, which is helpful in presurgical planning as well as during follow-up. Spin echo MRI does not visualize aberrant chordae tendineae.

The Society of Thoracic Surgeons National Congenital Heart Surgery Database Report: analysis of the first harvest (1994-1997)

This analysis summarizes the first report of the Society of Thoracic Surgeons National Congenital Heart Surgery Database Committee in association with Summit Medical Systems. Twenty-four centers joined the program at various dates of entry resulting in 18,894 enrolled patient records. This report compiled the relevant clinical features of 18 congenital heart categories over a 4-year period (1994-1997), which included 8,149 patient records. The data analyses are largely descriptive in character. Missing data points were described and not omitted in the analysis. Statistical analysis was not performed due to missing data points in some categories. Certain trends, however, could be identified and are discussed. The first Society of Thoracic Surgeons National Congenital Heart Surgery Database Report has succeeded in establishing a finite record that can be improved to establish universal national and international utility, risk stratification, and scholarly outcome analyses.

Double outlet right ventricle assessed with magnetic resonance imaging

In this article the value of magnetic resonance (MR) imaging for the evaluation of double outlet right ventricle (DORV) is reviewed from the literature and illustrated with several cases. MR imaging can be used for the determination of cardiac anatomy at initial diagnosis and may provide functional information during the follow-up of patients after surgical correction.

Perventricular [correction of Periventricular] closure of ventricular septal defects without cardiopulmonary bypass

BACKGROUND

Minimally invasive techniques are currently in use to close atrial and ventricular septal defects (VSD). Cardiopulmonary bypass (CPB) is instituted via the femoral vessels, which may cause injury to these vessels, especially in younger patients. The objectives of this study were to demonstrate the feasibility of perventricular [corrected] closure of muscular VSD (MVSD) and paramembranous VSD (PVSD) without CPB, using the Amplatz VSD device.

METHODS

Five Yucatan pigs with naturally occurring PVSD (3- to 7-mm diameter) and 5 dogs with surgically created MVSD (6- to 14-mm diameter) were subjects of this study. The VSDs were closed intraoperatively with a 7-French delivery sheath inserted through the free wall of the right (n = 5) or left ventricle (n = 5), under epicardial echocardiogram guidance. The animals were followed for 3 months.

RESULTS

There was no operative mortality. All MVSD closed after placement of the device. Closure rate of PVSD was 4 of 5 after placement and 3 of 5 after 3 months. One pig developed aortic incompetence at the last follow-up.

CONCLUSIONS

Perventricular closure of MVSD and PVSD is feasible. Avoidance of CPB can decrease recovery time, its complications, and trauma to the femoral vessels.

Double-outlet right ventricle with non-committed ventricular septal defect

OBJECTIVE

The term non-committed was used to define hearts in which the VSD was anatomically related to, or was close to, neither great vessel, being separated from both by considerable muscle. We report our experience of the surgical management of this subset, considered being of particular surgical relevance.

METHODS

Between January 1987 and December 1997, 23 patients having double-outlet right ventricle (DORV) with non-committed VSD underwent biventricular repair. Nine (39%) had undergone previous palliation. The median age was 20 months and the median weight was 8.5 kg. Two main types of repair were used: intraventricular baffle repair (n = 21) and arterial switch operation with VSD to pulmonary artery baffle (n = 2). At repair, 12 (52%) patients required concomitant VSD enlargement. In two other patients presenting with restrictive inlet VSD associated with tricuspid attachments, crossing the subaortic pathway biventricular repair was abandoned at operation.

RESULTS

There were two hospital deaths (9%, 70% CL: 3-19%). Eight patients (35%, 70% CL: 23-48%) underwent nine reoperations, six for subaortic stenosis. No late death occurred. At last visit, all patients were asymptomatic and only two had cardiac medication.

CONCLUSIONS

The biventricular repair of DORV with non-committed VSD is feasible in the vast majority of cases with comparable results to other subsets of DORV. After repair, the subaortic region is at risk for development of subaortic stenosis.

Clinical results of arterial switch operation for double-outlet right ventricle with subpulmonary VSD

OBJECTIVE

An arterial switch operation is considered a good alternative for the repair of double-outlet right ventricle (DORV) with atrioventricular concordance connection and subpulmonary ventricular septal defect (VSD) when intraventricular rerouting is not feasible. The clinical results of an arterial switch operation with ventricular septal defect closure for this anomaly were studied.

METHODS

Between 1986 and 1997, 27 patients ranging from 10 days to 5 years of age (mean 0.4 years) underwent an arterial switch operation with ventricular septal defect closure for the correction of double outlet right ventricle with subpulmonary VSD. The 50% rule was used to define double-outlet right ventricle. Arch anomalies were associated in nine cases, and were corrected either previously or simultaneously. A subarterial muscle resection was performed in 14 without any subsequent stenosis of the ventricular outflow tract. The relationship of the great arteries was mostly anteroposterior in 15 and mostly side by side in 12. The left coronary artery (main trunk or circumflex artery) courses behind the pulmonary artery in 15/27 (six/15 in the anteroposterior relation and ten/12 in the side by side relation). The Lecompte maneuver was used to reconstruct the pulmonary artery in all but five cases with a side by side relationship of the great arteries.

RESULTS

There was one operative death (3.7%) and three late deaths. The actuarial survival rate was 83 +/- 8% at 9 years. Right ventricular outflow tract obstruction including peripheral pulmonary stenosis developed in seven cases operated on in the early era. The reoperation free rate was 46 +/- 20% at 9 years.

CONCLUSION

Although double-outlet right ventricle with subpulmonary VSD has complex features, including an aortic arch obstruction and coronary artery anomalies, an optimal definitive surgical repair using an arterial switch operation can be performed safely with a thorough understanding of this variable anomaly. The prevention of right ventricular outflow tract obstruction at the time of an arterial switch operation may thus help improve the rate of late morbidity.

Biventricular hearts not amenable to biventricular repair

Many hearts, although considered morphologically biventricular, may not be candidates for a biventricular repair. Such patients are best placed on a Fontan algorithm. This article reviews in broad principles those hearts that, despite being biventricular, do not lend themselves to a two-ventricle repair.