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

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.

Neonatal repair of atypical double outlet right ventricle

BACKGROUND

A complex and rare form of double outlet right ventricle needs careful attention when choosing the optimal strategy for repair.

AIM OF THE STUDY

To point out retrospectively what could have been done differently in our unique patient.

METHODS

Primary repair was arranged in a neonate with double outlet right ventricle (of a non-committed ventricular septal defect type and lack of the outlet septum between the semilunar valves) with right aortic arch and dextro-malposition of great arteries.

RESULTS

We managed to achieve intraventricular rerouting via a right ventricular incision concomitantly with the arterial switch maneuver. The patient is doing well with an excellent hemodynamic status.

CONCLUSIONS

We considered that the radical approach we chose appeared to be sensible in this particular patient, although some other options could have been available.

Biventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect using intraventricular conduit

OBJECTIVE

Biventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect is preferred, but previously developed surgical procedures are complicated and associated with high mortality and morbidity. We developed a technique using an intraventricular conduit to connect the ventricular septal defect and the aorta in this anomaly in patients aged more than 2 years.

METHODS

Thirty-one patients (age 2-23 years; median, 5.4) with double-outlet right ventricle with noncommitted ventricular septal defect underwent biventricular repair with intraventricular conduit. A 16-mm or 19-mm polytetrafluoroethylene (Gore-Tex; WL Gore & Associates, Flagstaff, Ariz) vascular prosthesis was used to construct the intraventricular conduit rerouting the ventricular septal defect to the aorta, with enlargement of the ventricular septal defect and resecting the hypertrophic muscular bands in the bilateral conus when necessary. Follow-up was made in all patients with a median duration of 93 months (range, 8-140 months).

RESULTS

One patient died during hospitalization and 1 patient died at 8 months after operation, making the mortality 6.5%. The peak pressure gradient across the left ventricular outflow tract was less than 30 mm Hg in all patients but 1 (3.3%). In the last patient, it increased from 16 mm Hg early after operation to 50 mm Hg at 7 years follow-up. The peak pressure gradient across the right ventricular outflow tract ranged from 6 to 30 mm Hg in all patients. One patient had moderate mitral regurgitation with New York Heart Association class II. One patient had preoperative severe pulmonary arterial hypertension (mean pressure, 50 mm Hg) and was treated with bosentan. Other patients were in New York Heart Association class I.

CONCLUSIONS

Biventricular repair with intraventricular conduit is a relatively simple and safe procedure for patients aged more than 2 years with double-outlet right ventricle with noncommitted ventricular septal defect, with excellent early and midterm outcomes.

Essential Modifiers of Double Outlet Right Ventricle: Revisit With Endocardial Surface Images and 3-Dimensional Print Models

Hearts with double outlet right ventricle are a heterogeneous group of malformations in which a comprehensive diagnostic approach is required for tailored surgical management. This pictorial essay revisits essential modifiers of clinical and surgical importance in management of the patients with double outlet right ventricle using 3-dimensional volume-rendered endocardial surface images and 3-dimensional print models. Special emphasis is paid to the infundibular morphology, including the size and orientation of the outlet septum, relative to the margin of the ventricular septal defect, and the extent of the muscular infundibulum as an additional modifier of the distance between the ventricular septal defect margin and the arterial valve or valves.

Biventricular Repair of Double Outlet Right Ventricle: Preoperative Echocardiography and Surgical Outcomes

OBJECTIVE

To discuss the key anatomic features of double outlet right ventricle (DORV) assessed by preoperative echocardiography among patients treated with different types of biventricular repair.

METHODS

Surgical and echocardiographic databases were queried to identify patients who had undergone biventricular repair for DORV and had adequate preoperative echocardiographic imaging. All patients underwent pre- and postoperative echocardiography and clinical evaluation following discharge.

RESULTS

Two hundred sixty-two patients with DORV met the inclusion criteria of the study. The patients were divided into two groups-intraventricular tunnel repair (IVR) to the aorta (194 [74%] patients) or to the pulmonary artery with either concomitant arterial switch operation or double-root translocation (68 [26%] patients). Among 68 patients undergoing IVR to the pulmonary artery, 50 patients with transposition of the great arteries (TGA) type of DORV and 7 patients with remote ventricular septal defect (VSD) type underwent IVR plus arterial switch operation and 6 patients with TGA type and 5 patients with remote VSD type underwent IVR plus double-root translocation. There were three hospital deaths and one late death (overall operative mortality: 1.5%).

CONCLUSION

Preoperative echocardiography provided crucial data to estimate the feasibility of intraventricular tunnel creation to either the aorta or the pulmonary artery and to guide the selection of either arterial switch or double-root translocation. Biventricular repair could be achieved with favorable outcomes in most patients with DORV.

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.

Assessment of Double Outlet Right Ventricle Associated with Multiple Malformations in Pediatric Patients Using Retrospective ECG-Gated Dual-Source Computed Tomography

Purpose

To evaluate the feasibility and diagnostic accuracy of retrospective electrocardiographically (ECG)-gated dual-source computed tomography (DSCT) for the assessment of double outlet right ventricle (DORV) and associated multiple malformations in pediatric patients.

Materials and Methods

Forty-seven patients <10 years of age with DORV underwent retrospective ECG-gated DSCT. The location of the ventricular septal defect (VSD), alignment of the two great arteries, and associated malformations were assessed. The feasibility of retrospective ECG-gated DSCT in pediatric patients was assessed, the image quality of DSCT and the agreement of the diagnosis of associated malformations between DSCT and transthoracic echocardiography (TTE) were evaluated, the diagnostic accuracies of DSCT and TTE were referred to surgical results, and the effective doses were calculated.

Results

Apart from DORV, 109 associated malformations were confirmed postoperatively. There was excellent agreement (κ = 0.90) for the diagnosis of associated malformations between DSCT and TTE. However, DSCT was superior to TTE in demonstrating paracardiac anomalies (sensitivity, coronary artery anomalies: 100% vs. 80.00%, anomalies of great vessels: 100% vs. 88.57%, separate thoracic and abdominal anomalies: 100% vs. 76.92%, respectively). Combined with TTE, DSCT can achieve excellent diagnostic performance in intracardiac anomalies (sensitivity, 91.30% vs. 100%). The mean image quality score was 3.70 ± 0.46 (κ = 0.76). The estimated mean effective dose was < 1 mSv (0.88 ± 0.34 mSv).

Conclusions

Retrospective ECG-gated DSCT is a better diagnostic tool than TTE for pediatric patients with complex congenital heart disease such as DORV. Combined with TTE, it may reduce or even obviate the use of invasive cardiac catheterization, and thus expose the patients to a much lower radiation dose.

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.

Double-outlet right ventricle and double septal defects in a Rhesus macaque (Macaca mulatta)

A 6-year-old male India-origin Rhesus macaque (Macaca mulatta) presented with thin body condition and muscular atrophy. Thoracic auscultation revealed a grade VI/VI pansystolic murmur bilaterally. Radiographs showed cardiomegaly with significant left atrial and biventricular enlargement, a dilated pulmonary artery, and hepatomegaly. Electrocardiogram revealed a normal sinus rhythm interspersed with ventricular bigeminy. Hematology showed mild polycythemia and prerenal azotemia. Necropsy demonstrated double-outlet right ventricle with a large subaortic ventricular septal defect, subpulmonary stenosis, small atrial septal defect, and right ventricular hypertrophy. The major histological finding was severe chronic passive hepatic congestion. Double-outlet right ventricle is a rare congenital heart disease, both in human beings and animals.

Double-root translocation for double-outlet right ventricle with noncommitted ventricular septal defect or double-outlet right ventricle with subpulmonary ventricular septal defect associated with pulmonary stenosis: an optimized solution

BACKGROUND

Biventricular repair of double-outlet right ventricle (DORV) with noncommitted ventricular septal defect (VSD) or subpulmonary VSD, associated with pulmonary stenosis, remains controversial. The usual technique, Rastelli or réparation à l'étage ventriculaire (REV) procedure, may not meet a perfect biventricular outflow tract reconstruction in terms of hemodynamic performance and long-term outcome. Here we present an early result of an alternative solution for these anomalies by double-root translocation technique.

METHODS

Between August 2006 and August 2009, a total of 10 consecutive patients underwent a double-root translocation procedure, at a median age of 48 +/- 55 months (range, 1 to 16 years). The VSD was repaired with a Dacron patch, and VSD enlargement was done in 3 patients. The aortic translocation was done with (n = 4) or without (n = 6) coronary reimplantation. The neopulmonary artery was reconstructed with a monocusp bovine jugular vein patch (n = 8) or a homograft patch (n = 2). The mean follow-up interval was 21.9 +/- 11 months (range, 2 to 36). Biventricular outflow tract function was assessed by echocardiography.

RESULTS

There were no early or late deaths, and no required reoperations. Two patients required early support by extracorporeal membrane oxygenation. Postoperative echocardiography showed satisfactory hemodynamic effect of the reconstructed biventricular outflow tract and ventricular function. One patient had trivial aortic regurgitation and 4 patients had trivial or mild pulmonary insufficiency in follow-up.

CONCLUSIONS

The early results showed an optimized solution for DORV with noncommitted VSD or DORV with subpulmonary VSD, associated with pulmonary stenosis. Long-term benefits need to be evaluated with a larger number of patients and longer follow-up.

Surgical management of left ventricular outflow tract obstruction after biventricular repair of double outlet right ventricle

Regardless of the preoperative morphology and the type of operation, left ventricular outflow tract obstruction (LVOTO) after biventricular repair of double outlet right ventricle (DORV) may develop. This report presents our 10-yr experience with surgical management of LVOTO after biventricular repair of DORV. Between 1996 and 2006, 15 patients underwent reoperation for subaortic stenosis after biventricular repair of DORV. The mean age at biventricular repair was 23.3+/-18.3 months (1.1-64.2). Biventricular repairs included tunnel constructions from the left ventricle to the aorta in 14 cases and an arterial switch operation in one. The mean left ventricle-to-aorta peak pressure gradient was 54.0+/-37.7 mmHg (15-140) after a mean follow-up of 9.5+/-6.3 yr. We performed extended septoplasty in nine patients and fibromuscular resection in six. There were no early or late mortality. There was one heart block and one aortic valve injury after an extended septoplasty, and two and one after a fibromuscular resection. No patient required reoperation for recurrent subaortic stenosis. The mean pressure gradient was 11.2+/-11.4 mmHg (0-34) after a mean follow-up of 5.6+/-2.7 yr. Extended septoplasty is a safe and effective method for the treatment of subaortic stenosis, especially in cases with a long-tunnel shaped LVOTO.

Implications of incising the ventricular septum in double outlet right ventricle and in the Ross-Konno operation

OBJECTIVE

Incision into the ventricular septum in complex biventricular repair is controversial, and has been blamed for impairing left ventricular function. This retrospective study evaluates the risk of a ventricular septal incision in patients undergoing double outlet right ventricle (DORV) repair and Ross-Konno procedure.

METHODS

From January 2003 to September 2007, 11 patients with DORV had a ventricular septum (VS) incision and 12 DORV patients did not. Sixteen patients had a Ross-Konno, and 16 had an isolated Ross procedure. The ventricular septal incision was made to match at least the diameter of a normal aortic annulus. In DORV, the VSD was enlarged superiorly and to the left. In the Ross-Konno, the aortic annulus was enlarged towards the septum posteriorly and to the left.

RESULTS

The median follow-up for the study is 19 months (1 month-4 years). For DORV, there were no significant differences in discharge mortality (p=0.22), late mortality (p=0.48), or late mortality plus heart transplant (p=0.093). Although patients with DORV and VSD enlargement have a more complex postoperative course, there were no differences in ECMO use (p=0.093), occurrence of permanent AV block (p=0.55), left ventricular ejection fraction (LVEF) (p=0.40), or shortening fraction (LVSF) (p=0.50). Similarly, for the Ross-Konno there were no significant differences in discharge mortality (p=0.30), late mortality (p=NS), LVEF (p=0.90) and LVSF (p=0.52) compared to the Ross, even though the Ross-Konno patients were significantly younger (p<0.0001).

CONCLUSION

Making a ventricular septal incision in DORV repair and in the Ross-Konno operation does not increase mortality and does not impair the LV function. The restriction of the VSD remains an important issue in the management of complex DORV. These encouraging results need to be confirmed by larger series.

Intracardiac repair of double outlet right ventricle

Intracardiac repair of double outlet right ventricle (DORV) remains controversial. DORV is a particular mode of ventriculo-arterial connection and not a specific congenital heart disease. It can exhibit a wide spectrum of anatomic and physiologic variations. This heterogeneity has naturally led to controversies over the anatomical definition, classification schemes, and the techniques for surgical repair. From a surgical standpoint, the functional classification that was adopted together by the Society of Thoracic Surgeons (STS), The European Association of Cardio-Thoracic Surgery (EACTS) and the Association of the European Pediatric Cardiologists (AEPC), provides useful information to understand the anatomical variations and the choice of the surgical technique. The lesions that remain a surgical challenge are those where "200% of the great vessels" arise from the right ventricle. Namely: DORV-nc-VSD and DORV-AVSD-heterotaxy. Both of these lesions have traditionally been indications for single-ventricle palliation. In our series, there was one death in 15 of these challenging patients (6.7% mortality) following bi-ventricular repair. Two patients required a one and a half repair. Long-term results of biventricular repair of complex DORV are not yet available. These data would be crucial to validate the intracardiac repair technique."

Biventricular repair of double outlet right ventricle with noncommitted ventricular septal defect

Double outlet right ventricle (DORV) with noncommitted ventricular septal defect (VSD) (DORVncVSD) represents the most extreme form of DORV, raising challenging surgical difficulties for biventricular repair. The considerable distance between the VSD and the aorta is primarily because of the very abnormal location of the aorta. The definition of DORVncVSD includes: (1) a VSD distant (greater than aortic diameter) from both arterial valves; (2) both great vessels arising fully from the right ventricle; and (3) a double conus. Double outlet right ventricle with noncommitted ventricular septal defect is a primitive right ventricle, as seen during embryologic development, characterized by the presence of the entire conotruncus from the right ventricle. One surgical technique for repair of DORVncVSD is rerouting of the VSD to the aorta by a long intraventricular tunnel. This technique is limited by the presence of conal tricuspid chordae and by the distance between the tricuspid and pulmonary valves, and is associated with an important risk of subaortic obstruction. Rerouting through the pulmonary artery followed by arterial switch seems a more satisfactory surgical solution. When the VSD is distant from the aorta, it is almost always quite close to the pulmonary artery. Rerouting to the pulmonary artery creates a smaller channel, and its application is not limited by the presence of tricuspid chordae or the tricuspid-to-pulmonary valve distance. However, the arterial switch frequently involves relocating complex coronary arteries.

The morphologic nature of noncommitted ventricular septal defects in specimens with double-outlet right ventricle

BACKGROUND

Lev's contribution to the understanding of the morphology of hearts with double-outlet right ventricle and the surgical feasibility for correction is important and remains in current use. However, the term noncommitted ventricular septal defect remains enigmatic. The aim of this study was to elucidate the morphologic nature of the noncommitted ventricular septal defect in view of its surgical implications.

METHODS

We examined 67 specimens with double-outlet right ventricle, focusing on the relationship of the ventricular septal defect to the semilunar orifices.

RESULTS

The defect was subaortic, subpulmonary, or doubly committed in 55 specimens. In a further 8 specimens, the defect opened into the outlet portion of the right ventricle, but the distance between the ventricular septal defect and the semilunar orifice was extensive, either because of extreme dextroposition of the aorta or a broad ventriculoinfundibular fold, which, in some cases, was associated with a long-outlet septum. A truly noncommitted ventricular septal defect was found in the inlet in the remaining 4 specimens. An atrioventricular septal defect without extension to the outlet was present in 3 cases, and a ventricular septal defect limited to the inlet was found in another case. The ventriculoinfundibular fold, part of the outlet septum and septal band or septomarginal trabeculation, had fused to form a crestlike structure. The septomarginal trabeculation is a useful landmark in the right ventricle to differentiate the inlet from the outlet in different forms of double-outlet right ventricle.

CONCLUSION

We do not suggest to discard the Lev terminology but rather to differentiate the noncommitted ventricular septal defect into 2 types: the truly noncommitted defect of the inlet type and the not-directly-committed defect, which does open into the outlet portion of the right ventricle. The implication for the surgeon is 2-fold. The tricuspid valve or right part of the atrioventricular valve is interposed between the noncommitted ventricular septal defect and the semilunar orifice. The not-directly-committed defect opens into the outlet portion of the right ventricle but is not directly subaortic or subpulmonary.

Biventricular repair for double-outlet right ventricle

Double-outlet right ventricle (DORV) is a heart malformation that describes an anomalous ventriculoarterial connection which can be associated with considerable variant of associated lesions. When this malformation is present with two ventricles, biventricular repair is feasible in the vast majority of cases. This report describes the surgical techniques for biventricular repair in all forms of encountered DORV, as well as the surgical strategy employed at our institution. 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.