CASE REPORT

Aneurysmal aorto-left ventricular tunnel causing right ventricularoutflow tract obstruction, associated with bicuspid aortic valve

Rodica Toganel • Theodora Benedek •

Carmen Suteu • Imre Benedek

Received: 28 August 2013 / Accepted: 8 November 2013

� Springer Japan 2013

Abstract We report the case of a newborn with an

aneurysmal aorto-left ventricular tunnel causing significant

paravalvular aortic regurgitation and obstruction of the

right ventricular outflow tract (RVOT), coexisting with a

bicuspid aortic valve. The coexistence of the two malfor-

mations together with the obstruction of the RVOT is very

rare. In this case, the prompt diagnosis and surgery led to

significant improvement of the clinical status and to

recovery of the left ventricular function (increase of the

ejection fraction from 21 to 41 %), underlining the

importance of early diagnosis in this rare malformation.

Keywords Aorto-ventricular tunnel � Congenital

heart disease � Aortic regurgitation

Introduction

Congenital aorto-left ventricular tunnel is a rare heart

disease, accounting for up to 0.1–0.5 % of congenital heart

malformations, with a higher frequency in male patients

[1]. This anomaly was first described by Levy et al. in 1963

[2], after which very few cases have been reported.

Aorto-left ventricular tunnel consists of an extracardiac

direct communication between the aorta and the left ven-

tricle. In most of these cases, the communication originates

from the aorta above the sinotubular junction and

terminates in the left ventricle, below the right coronary

cusp [3]. The etiology of this malformation remains

uncertain; however, several authors have suggested that it

is linked to the maldevelopment of the cushions, giving rise

to the pulmonary and aortic roots, associated with an

abnormal separation of these structures [4]. In nearly half

of these cases, associated defects of the aortic and pul-

monary valves or of the proximal coronary arteries are

recorded [5, 6].

Case report

We present the case of a newborn (male, gestational age 37

weeks, birth weight 3,550 g), referred to our institution at

21 days after his birth for a continuous systolic–diastolic

left parasternal murmur and symptoms of heart failure:

severe dyspnea, diaphoresis, and unsatisfactory growth

rate. Chest X-ray revealed significant cardiomegaly, with a

cardiothoracic index of 0.75 and a broad upper mediastinal

shadow from the enlarged ascending aorta. The electro-

cardiogram showed signs of left ventricular hypertrophy.

Echocardiography showed a dilated left ventricle with a

very low ejection fraction (EF) of 21 %, and a significant

bidirectional turbulent flow via a tubular communication

between the aorta and the left ventricle, located anterior to

the aortic root and bypassing the aortic valve (Fig. 1). The

orientation of the flow was from the left ventricle to the

aorta in systole and from the aorta to the left ventricle,

resulting in a significant paravalvular aortic regurgitation,

in diastole. Echocardiography identified both ends of the

communication, the aortic one above the coronary sinus

and the left ventricular one below the right coronary cusp.

According to this echocardiographic aspect, the commu-

nication was diagnosed as an aorto-left ventricular tunnel,

R. Toganel � T. Benedek � C. Suteu � I. Benedek

University of Medicine and Pharmacy Tirgu Mures, Tirgu

Mures, Romania

T. Benedek (&) � I. Benedek

Cardiomed Medical Center Tirgu Mures, 22 decembrie 1989 no.

76–78, Tirgu Mures, Romania

e-mail: hintea_teodora@yahoo.com

123

Heart Vessels

DOI 10.1007/s00380-013-0445-8

which appeared to be aneurysmal, with a diameter of 6 mm

at the aortic end and 8 mm at the ventricular end.

Echocardiography also revealed a bicuspid aortic valve

with minor valvular regurgitation, and a significant dila-

tation of the ascending aorta (aorta diameter 18.6 mm, with

Z-scores of 5.86 at the level of the aortic valve and 7.07 at

the level of the ascending aorta). Because of its aneurysmal

nature, the tunnel compressed the right ventricular outflow

tract (RVOT), causing obstruction at this level (peak sys-

tolic gradient 20 mm Hg) (Fig. 2).

Surgical intervention was decided upon, and the patient

was operated on at week 5. The repair was achieved by the

obliteration of the tunnel under extracorporeal circulation.

Postoperatively the status of the patient significantly

improved, and he was discharged on day 16 after surgery.

Echocardiography at discharge revealed a recovered left

ventricular function (volumetric EF of 41 %), minor aortic

regurgitation, and no obstruction at the RVOT.

Discussion

An aorto-left ventricular tunnel is one of the most impor-

tant causes of severe heart failure in newborns, caused by

the associated significant regurgitation via the tunnel from

the aorta to the left ventricle [7]. Even though the diagnosis

of this anomaly could be easily established in the prenatal

period, it is usually diagnosed only after birth, when

symptoms and signs of left ventricular volume overload

become evident.

Very few reports of aortoventricular tunnels are pre-

sented in the literature, most of them describing the asso-

ciation of the tunnel with other coexisting abnormalities of

the aortic valves or coronary arteries [8]. However, to the

best of our knowledge there is no case published so far

describing the coexistence of an aneurysmal tunnel with an

RVOT obstruction and bicuspid aortic valve at the same

time. It has been suggested in the literature that an aneu-

rysmal aorto-left ventricular tunnel could cause RVOT

obstruction owing to the presence of the right ventricular

infundibulum in the proximity of the aortic sinus, where

the tunnel terminates [9]. In this case, a left ventricular hole

of the defect larger than the aortic one caused the aneu-

rysmal dilation of the tunnel. As the tunnel was located in

immediate proximity to the RVOT, anterior to the aortic

root, the aneurysmal dilation of the tunnel caused bulging

of the septum into the right ventricle, which could explain

the reversible mild RVOT obstruction.

The coexisting anomaly of the aortic valve most likely

has a common etiology with the tunnel, with both being

Fig. 1 Echocardiographic

examination, modified

parasternal long-axis view.

Right B-mode examination:

junction of tunnel (T) to Aorta

(Ao) above the coronary sinus,

measured as 6 mm in diameter,

and to the left ventricle (LV),

measured as 8 mm in diameter.

MV mitral valve, LA left atrium,

AoV aortic valve. Left Color

Doppler examination: flow

through the tunnel in diastole,

creating a significant aortic

paravalvular regurgitation. The

communication is visible in its

entire length (arrow)

Fig. 2 Echocardiographic examination, aortic short-axis view. Visu-

alization of turbulent flow in the RVOT (arrow), compressed by the

aneurysmal tunnel. PA pulmonary artery, RVOT right ventricular

outflow tract

Heart Vessels

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caused by a maldevelopment of the cushions, giving rise to

the aortic root in the embryonic period.

The coexistence of the two malformations together with

the obstruction of the RVOT creates a very rare and

interesting clinical picture in this case. However, as the

valvular regurgitation associated with the bicuspid aortic

valve was only mild, it did not require repair. Therefore the

surgery consisted only of the repair of the tunnel, which led

to the disappearance of the paravalvular aortic regurgita-

tion, recovery of the left ventricular function, and regres-

sion of the RVOT obstruction.

The differential diagnosis of an aorto-left ventricular

tunnel includes ventricular septal defect, rupture of the

sinus of Valsalva, and coronary artery–left ventricular fis-

tula [10, 11]. The echocardiographic appearance of the

tunnel shows many similarities with a subaortic ventricular

septal defect, given the opening of the ventricular end of

the tunnel in the subaortic region [12, 13]. In our case, the

ventricular septal defect was excluded by the absence of

any shunt or right ventricular overload. A ruptured sinus of

Valsalva was excluded by the absence of a dilated sinus of

Valsalva, and the coronary artery–ventricular fistula was

excluded by the normal appearance of the coronary arter-

ies. Interestingly, in this case the severe aortic paravalvular

regurgitation within the tunnel was associated with a mild

aortic valvular regurgitation caused by the bicuspid aortic

valve. The coexistence of valvular and paravalvular aortic

regurgitation can frequently lead to diagnostic errors,

confounding the rare malformation (the tunnel) with the

more frequent one (valvular regurgitation caused by the

bicuspid aortic valve), especially when the regurgitant flow

is eccentric and is visualized in apical views. The false

attribution of the regurgitant flow within the tunnel to the

regurgitation across the bicuspid valve leads not only to the

missed diagnosis of the tunnel but also to overestimation of

the severity of aortic valve disease.

The optimal management of patients with an aortoven-

tricular tunnel consists of early diagnosis followed by a

prompt surgical repair. In the presence of a symptomatic

newborn with left ventricular failure, echocardiographic

examination should be performed as soon as possible [14].

However, owing to the very rare nature of this malforma-

tion, the tunnel remains unrecognized in many cases. Given

the importance of immediate surgery for preventing evo-

lution toward severe left ventricular failure, the examiners

should search for this pathologic appearance in any fetus or

newborn with signs of aortic regurgitation. Furthermore,

prenatal diagnosis could indicate the referral for delivery in

a tertiary care center where all the necessary facilities for

appropriate assistance, including cardiac surgery for an

immediate postnatal surgical repair, are available.

References

1. McKay R, Anderson RH, Cook AH (2002) The aorto-ventricular

tunnels. Cardiol Young 12:563–580

2. Levy MJ, Lillehei CW, Anderson RC, Amplatz K, Edwards JE

(1963) Aortico-left ventricular tunnel. Circulation 27:841–853

3. Horvath P, Balaji S, Skovranek S, Hucin B, de Leval MR, Stark J

(1991) Surgical treatment of aortico-left ventricular tunnel. Eur J

Cardiothorac Surg 5:113–117

4. Mitropoulos FA, Laks H, Kanakis MA, Levi D (2006) Aorto-left

ventricular tunnel: an alternative surgical approach. Ann Thorac

Surg 82:1113–1115

5. Mori Y, Takahashi K, Nakanishi T (2013) Complications of

cardiac catheterization in adults and children with congenital

heart disease in the current era. Heart Vessels 28:352–359

6. Le Gloan L, Mongeon FP, Mercier LA, Dore A, Marcotte F,

Ibrahim R, Asgar A, Miro J, Poirier N, Khairy P (2013) Tetralogy

of Fallot and aortic root disease. Expert Rev Cardiovasc Ther

11:233–238

7. Nezafati MH, Maleki MH, Javan H, Zirak N (2010) Repair of

aorto-left ventricular tunnel arising from the left sinus of Val-

salva. J Card Surg 25:345–346

8. Singh SK, Dwivedi SK, Kumar A, Vijay SK, Rajput N, Devenraj

V, Lal Sahni J (2012) Aneurysmal aorto-right ventricular tunnel.

Ann Thorac Surg 93:e21–e22

9. Troubil M, Lonsky V, Petr S (2010) Aorto-left ventricular tunnel

causing severe aortic regurgitation in adult man. Eur Heart J

31:145

10. Yoshino S, Minagoe S, Yu B, Kosedo I, Yamashita M, Ishizawa

M, Kono M, Setoguchi M, Nakashima H, Matsuoka T, Suehiro S,

Yotsumoto G, Yamashita M, Tei C (2013) Cardiac tamponade

due to rupture of coronary artery fistula to the coronary sinus with

giant aneurysm of coronary artery: usefulness of transthoracic

echocardiography. Heart Vessels 28:536–540

11. Zanjani KS, Niwa K (2013) Aortic dilatation and aortopathy in

congenital heart diseases. J Cardiol 61:16–21

12. Knott-Craig CJ, van der Merwe PL, Kalis NN, Hunter J (1992)

Repair of aortico-left ventricular tunnel associated with subpul-

monary obstruction. Ann Thorac Surg 52–54:557–559

13. Wei Y, Wang X, Zhang S, Hou L, Wang Y, Xu Y, Sun Q, Zhao H

(2012) Transcatheter closure of perimembranous ventricular

septal defects (VSD) with VSD occluder: early and mid-term

results. Heart Vessels 27:398–404

14. McKay R (2007) Aorto-ventricular tunnel. Orphanet J Rare Dis

2:41

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