Two-Dimensional and Real-Time Three-Dimensional Echocardiographic Fetal Diagnosis of Aorto-Ventricular Tunnel

Abstract

A 22-gestational-week-old female fetus was referred to our prenatal echocardiographic unit to evaluate her left ventricular dilatation and dysfunction. An aorto-ventricular tunnel was visualized (Figure 1a and 1b), causing marked left ventricular diastolic overload, overt fetal heart failure, hydrops, and polidramnios. The mother was informed about the possibility of spontaneous abortion or premature delivery, and the pregnancy was closely monitored with serial fetal echographic and echocardiographic evaluations. At 33 weeks of gestational age (GA), the signs of fetal heart decompensation were still present, but the fetus' vitality and growth were satisfactory. A real-time 3D (RT3-D) echocardiographic evaluation was performed, which allowed the precise visualization of the site and dimension of the aorto-ventricular tunnel (Figure 2a).At 35 weeks of GA, a programmed cesarean section was performed, and the mother gave birth to a 2.2-kg vital girl.APGAR score was 4/1Ј 7/5Ј 8/10Ј. The neonate was intubated and ventilated in the operating room and transferred to the neonatal intensive care unit. At 2 days of age, surgical intervention was performed. At the surgical inspection, the aorto-ventricular tunnel location and dimension were superimposed on the RT3D visualization (Figure 2b). The postoperative course was characterized by low cardiac output syndrome and difficulty in achieving respiratory autonomy. The neonate was extubated on the 7th postoperative week and discharged home on the 9th postoperative week in good general condition and weighing 2.5 kg. The predischarge echocardiographic evaluation (Figure 3) showed marked hypertrophy of the left ventricle, good ventricular function, and dilation of the ascending aorta and aortic arch.As far as we are aware, this is the first report in the literature of a fetal diagnosis of an aorto-ventricular tunnel.

Aortopulmonary Window with Atrial Septal Defect: Prenatal Diagnosis, Management and Outcome

“…The combination of a defect between aorta and pulmonary artery with two normal semilunar valves is the typical echocardiography finding in APW, the short axis view of the aortopulmonary septum in a perpendicular plane being very helpful to diagnose APW. Other signs such as dilation of the cardiac outlets or pulmonary regurgitation are only indirect clues to the presence of APW [3,8,9] . It may sometimes be difficult to differentiate APW from truncus arteriosus in APW type III [5] .…”

Aorto-ventricular tunnel

“…Transthoracic cross-sectional imaging in a parasternal long-axis view, sometimes with clockwise rotation of the probe [ 11 , 39 ] demonstrates the tunnel itself, as well as its aortic origin and left ventricular opening. Both two-dimensional and real-time three dimensional echocardiography have also established reliable fetal diagnosis [ 40 - 42 ]. On color-Doppler studies, diastolic flow is seen passing from the aorta to the left ventricle, and systolic, from the ventricle to the aorta.…”

“…Hypertrophy and dilatation of the left ventricle with progressive reduction of its shortening fraction are consistent features, and there is often disproportionate dilatation of the aortic root with apparent incompetence of the valve. Using color flow Doppler imaging, blood flow around the aortic valve has been demonstrated [ 16 , 42 ], as well as flow specifically within the tunnel itself [ 40 , 41 ]. There are no known molecular markers for aorto-ventricular tunnel at present, and it is not associated with any recognized genetic syndrome.…”

Congenital aortico-left ventricular tunnel in fetuses and infants

“…However, one case died after surgery because heart failure did not improve. Three cases did not develop heart failure during the fetal period, but surgical repair was performed on all cases [3][4][5][6][7][8][9]. Martins et al [1] reported that eight of 11 cases of ALVT developed heart failure within 6 months after birth.…”