Double Outlet Right Ventricle

Kelly Christy, Jusuf Rachmat

Department of Cardiac, Thoracic and Vascular Surgery, Faculty of Medicine, University of Indonesia,
Jakarta, Indonesia.

Double outlet right ventricle (DORV) is a group of complex congenital heart

abnormalities.The term "Double Outlet Right Ventricle" refers to any cardiac anomaly in which
both the aorta and pulmonary trunk originate, predominantly or entirely, from the right ventricle
(RV)1 In this situation, the left ventricle (LV) has no direct outlet to either great artery and ejects
through an interventricular communication, usually referred to as a "ventricular septal defect"
(VSD), (which is almost invariably present) into the right ventricle. Rarely there may be no "VSD"
and the LVis then extremely hypoplastic.

Embriology
In general, from a surgical perspective, defining the lesion as double outlet right ventricle
is reasonable when more than 50% of both of the great arteries arise from the right ventricle.
From the morphological standpoint, some suggest that the absence of the fibrous continuity
between the arterial and atrioventricular valves is a feature of double outlet right ventricle.
Historically, DORV was thought to result from a failure of the normal spiraling of the aorta
and pulmonary trunk, resulting in abnormal positioning. However, more recent research confirms
that the primitive right ventricle is in fact a DORV, containing the conotruncus. If migration of the
aortic side of the conotruncus toward the mitral valve is incomplete, the DORV anatomy persists.
DORV is frequently associated with other intracardiac or extracardiac malformations.

Frequency
In the United States, the incidence of double outlet right ventricle is 0.09 cases per 1000
live births. Double outlet right ventricle comprises about 1-1.5% of all congenital heart disease.

History
DORV was first described in 1703. It was considered to be one type of transposition of the
great arteries (TGA). In 1898, Vierordt referred to DORV as a partial transposition because only
the aorta was actually transposed as the pulmonary artery originates appropriately from the right
ventricle.
In 1949, Taussig and Bing described a patient with “complete transposition of the aorta
and levoposition of the pulmonary artery.” They described the first reported case in which both
great arteries arose from the right ventricle, but the VSD was related to the pulmonary artery and

1
1. Wilkinson JL: Double Outlet Ventricle, in Anderson RH, Baker EJ, Macartney FJ, Rigby ML, Shinebourne EA,
Tynan M (eds): Paediatric Cardiology. London, Churchill Livingstone, 2002, pp1353-1382
not the aorta, as had been the case in all previous reports. In 1952, Braun et a described a case in
which “the right ventricle serves as a double outlet ventricle.” They classified it as a partial
transposition of the Fallot type.
The term “double-outlet right ventricle” was first used by Witham in 1957. He considered
it to be a partial transposition complex in which both great arteries arose from the right ventricle.
He divided his cases of DORV into two groups—the Fallot type and the Eisenmenger type—
depending on whether pulmonary stenosis was present or absent.
In 1982, Van Praagh developed the most widely accepted classification of DORV, which included
the following
• DORV with a subaortic VSD
• DORV with a subpulmonary VSD
• DORV with a doubly committed (both subaortic and subpulmonic) VSD
• DORV with a remote VSD (noncommitted)
In 2000, the Society of Thoracic Surgeons and the European Association of Cardiothoracic
Surgery adopted four types of DORV on the basis of clinical presentation and treatment 27:
• VSD-type: DORV with subaortic VSD
• Fallot-type: DORV with subaortic or double committed VSD and pulmonary outflow stenosis
• TGA-type (Taussig-Bing): DORV with a subpulmonary VSD
• Noncommitted VSD–type: DORV with a remote VSD
These four types differ significantly in their surgical treatment, postoperative management, and
prognosis.

Clinical description
Double outlet right ventricle with subaortic interventricular communication (VSD) and pulmonary
stenosis (Fallot type).2
In this common variant, the clinical picture is indistinguishable from classic Tetralogy of Fallot.
A systolic murmur is usually heard from the newborn period (due to the pulmonary stenosis).
Cyanosis develops and progresses during the early months of life. Hypoxic spells may occur.
Management is largely surgical and complete repair is performed as a primary procedure if
feasible (usually within the first six to twelve months). It involves placement of an intraventricular
patch to direct left ventricular blood to the aorta and relief of right ventricular outflow
obstruction (pulmonary stenosis). Some infants, especially those who develop severe cyanosis
early in infancy, may have a preliminary "shunt" operation prior to complete repair.

2
Neufeld HN, Du Shane JW, Edwards JE: Origin of both great vessels from the right ventricle. II. With pulmonary
stenosis. Circulation 1961;2:603-612
Double outlet right ventricle with subpulmonary interventricular communication (VSD) (Taussig
Bing Malformation)3
The clinical picture is essentially the same as that of Transposition with associated VSD.
Presentation is often one of cyanosis in the newborn period with early development of symptoms
of "heart failure". Increasing breathlessness, poor feeding and slow weight gain are prominent
features. A murmur is usually present, even in the absence of pulmonary stenosis (which is
uncommon). An associated coarctation of the aorta is frequent and usually leads to very early
onset of heart failure (e.g. in the first week of life). Management is largely surgical and requires
a repair that leaves the left ventricle connected to the aorta and the right ventricle feeding the
pulmonary circulation. This may be achieved by the use of an intraventricular patch connecting
the LV to the aorta (which is often difficult to achieve). Alternatively a patch may be placed to
connect the LV to the pulmonary artery (which is easier to perform) and an "Arterial Switch"
operation (as for transposition) may be done so that the left ventricle is connected to the aorta
and the RV to the pulmonary circulation. The operation is usually carried out within the first 1 –
3 months.
Double outlet right ventricle with subaortic interventricular communication and without
pulmonary stenosis4
The blood from the left ventricle is directed preferentially to the aorta (as the interventricular
communication is close to this artery). In the absence of any pulmonary stenosis there is
increased flow to the pulmonary circulation and the clinical picture resembles that of a large,
isolated, VSD. Cyanosis is very mild or absent and symptoms usually develop gradually over the
first few months of life, with poor feeding and weight gain accompanied by increasingly apparent
breathlessness and an increasingly loud heart murmur, which may not be present initially. If an
associated coarctation is present symptoms appear earlier and are more severe. Surgical repair
is usually performed as a primary procedure at an age between one month and six months. Repair
involves placement of an intraventricular patch to direct left ventricular blood to the aorta.
Other variants
In other malformations in which DORV is present the clinical picture commonly resembles that
seen in one of the variants described above. The time of onset and severity of symptoms tend to
depend often on associated defects, such as coarctation, which usually leads to early onset of
heart failure or pulmonary stenosis / atresia, associated with cyanosis as the main feature. Most
affected patients can undergo surgical repair, though in the more complex variants complete
"repair" may not be feasible (especially those with Isomerism of Right Atrial Appendages) and
palliation involving a Cavo-Pulmonary shunt or Fontan operation may be performed.

3
Beuren A: Differential diagnosis of the Taussig-Bing heart from complete transposition of the great vessels with a
posteriorly overriding pulmonary artery. Circulation. 1960;21:1071-1087
4
Neufeld HN, Du Shane JW, Wood EH, Kirklin JW, Edwards JE: Origin of both great vessels from the right ventricle.
I. Without pulmonary stenosis. Circulation 1961;23:399-412
Timing Operation
Except for TOF type, which usually has pulmonary hypotension (PH), the other three types
frequently induce PH. Preoperative PH was concerned as an important risk factor for early deaths
in the surgical treatment of DORV.5The onset of PH often leads to a progressive reduction in
exercise capacity and fatigue resulting from impaired respiratory and heart function, which cause
stunted childhood development. PH usually arises early and eventually results in heart and lung
dysfunction, with a missed opportunity to performing surgery. Therefore, once the diagnosis is
confirmed, surgical treatment should be considered.
It is generally considered that these patients often develop significant congestive heart
failure due to a large left-to-right shunt, and surgical repair should be carried out in the first
several months of life.Pathological changes in patients with DORV are varied, necessitating an
individualized surgical strategy to optimize success. The suture technique used in intracardiac
channel repair of VSD type DORV should be sufficient to prevent residual shunt formation. In
cases of restricted VSD, enlargement of the outflow defect should be carried out, with attention
paid to avoid outflow tract stenosis from both the left and right ventricular chambers. To avoid
RVOT stenosis, the tract should simultaneously be enlarged with a patch.
For TGA type DORV, an arterial switch operation remains the best choice. During the
operation, coronary anastomotic patency should be confirmed, and care taken to prevent
distortion and stenosis. Aortic and pulmonary valves should be protected. It is important to avoid
stenosis of the pulmonary artery and its branches during pulmonary artery anastomosis. If the
aorta and pulmonary artery are located in an anterior and posterior position and the VSD is below
the pulmonary valve, arterial switch surgery can be performed after establishing an intracardiac
channel.
Mustard or Senning surgical techniques are generally safe because of their relative
simplicity. Both methods are useful for neglected cases with severe PH, cyanosis, and hypoxia, in
which the best opportunity for surgery has been missed. These palliative procedures will improve
hypoxia and overall quality of life; however, the operative risk is high.

Outcome and Prognosis

A study by Li et al found an estimated overall 5-year survival rate of 87.1% following
biventricular repair of double outlet right ventricle with noncommitted VSD.5 The study included
75 patients (mean age 2.2 years) with the condition, with five types of biventricular repair
performed. Surgery involved rerouting the VSD to either the aorta (40 patients) or the pulmonary
artery (35 patients), with tunnel obstructions occurring in 10 patients who underwent the VSD-

5
Li S, Ma K, Hu S, Hua Z, Yang K, Yan J, et al. Surgical outcomes of 380 patients with double outlet right ventricle who
underwent biventricular repair. J Thorac Cardiovasc Surg. 2014;148:817–24. doi: 10.1016/j.jtcvs.2014.06.020
to-aorta procedure, versus none of the other patients, during the mean 4.1-year follow-up. The
investigators also found that patients who underwent a concomitant tricuspid procedure had a
significantly reduced likelihood of intracardiac obstruction, with no tricuspid regurgitation or
stenosis developing
In a large series analyzing outcomes in patients with double outlet right ventricle (DORV)
from 1980-2000, Brown et al reported that the 15-year overall survival rate (including the
patients who underwent no surgical intervention) is 56%. 6 Brown et al reported that 15-year
survival rates after repair for noncomplex double outlet right ventricle and Taussig-Bing anomaly
were 95% and 89%, respectively.
Small left-sided structure, including left ventricle and mitral valve, structural abnormality of the
mitral valve, and aortic arch obstruction, has been identified as a risk factor for death after repair

6
Brown JW, Ruzmetov M, Okada Y, Vijay P, Turrentine MW. Surgical results in patients with double
outlet right ventricle: a 20-year experience. Ann Thorac Surg. 2001 Nov. 72(5):1630-5.