Aorto-ventricular tunnel

Abstract

Aorto-ventricular tunnel is a congenital, extracardiac channel which connects the ascending aorta above the sinutubular junction to the cavity of the left, or (less commonly) right ventricle. The exact incidence is unknown, estimates ranging from 0.5% of fetal cardiac malformations to less than 0.1% of congenitally malformed hearts in clinico-pathological series. Approximately 130 cases have been reported in the literature, about twice as many cases in males as in females. Associated defects, usually involving the proximal coronary arteries, or the aortic or pulmonary valves, are present in nearly half the cases. Occasional patients present with an asymptomatic heart murmur and cardiac enlargement, but most suffer heart failure in the first year of life. The etiology of aorto-ventricular tunnel is uncertain. It appears to result from a combination of maldevelopment of the cushions which give rise to the pulmonary and aortic roots, and abnormal separation of these structures. Echocardiography is the diagnostic investigation of choice. Antenatal diagnosis by fetal echocardiography is reliable after 18 weeks gestation. Aorto-ventricular tunnel must be distinguished from other lesions which cause rapid run-off of blood from the aorta and produce cardiac failure. Optimal management of symptomatic aorto-ventricular tunnel consists of diagnosis by echocardiography, complimented with cardiac catheterization as needed to elucidate coronary arterial origins or associated defects, and prompt surgical repair. Observation of the exceedingly rare, asymptomatic patient with a small tunnel may be justified by occasional spontaneous closure. All patients require life-long follow-up for recurrence of the tunnel, aortic valve incompetence, left ventricular function, and aneurysmal enlargement of the ascending aorta.

Aorto-Left Ventricular Tunnel in a Multianeurysmal Heart

“…However, cystic medial degeneration has been demonstrated in an aortic aneurysm from a patient with repaired ALVT, making connective tissue disease an important contender for the underlying defect. 1 The presence of multiple cardiac aneurysms in this patient adds credence to this hypothesis. However, although the patient did have a marfanoid habitus with a reduced upper to lower segment ratio and a positive wrist and thumb sign (Figure 6), he did not meet the revised Ghent criteria for Marfan syndrome.…”

Clinical implications of prenatal diagnosis of aorto-left ventricular tunnel on postnatal treatment and final outcome

“…Its incidence ranges between 0.001 and 0.1% of all congenital heart defects seen postnatally but is much higher in prenatal heart specimens reaching 0.5% [1][2][3] . Nevertheless, there are no more than 20 antenatally diagnosed AVLT cases reported in the literature.…”

Surgical Repair of an Aortico-Left Ventricular Tunnel with Acute Infective Endocarditis

“…4) Up to now, very few cases of this abnormality have been reported in the world literature. 5) The etiology of ALVT remains unknown but there are several theories to explain the pathogenesis, including an abnormal coronary artery, early or intrauterine rupture of a sinus of Valsalva aneurysm, malformation of the distal bulbus cordis, early aortic dissection similar to Marfan syndrome, or persistence of embryonic rests of the fifth aortic arch. The clinical symptoms are not typical.…”