Congenital Aorto-Right Ventricular Fistula Associated with Pulmonary Hypertension in an Old Female Patient.

We report a late clinical presentation of an aorto-right ventricular fistula (RVF) extending from the right sinus of Valsalva into the RV outflow tract with significant left-to-right shunt and severe pulmonary hypertension. A three-dimensional transesophageal echocardiogram and a chest-computed tomography scans were performed to better characterize the abnormality. Aorto- RVF can be either congenital or acquired, secondary to endocarditis, Valsalva aneurysm rupture, chest trauma, or aortic dissection.

INTRODUCTION

Aorto-right ventricular fistula (RVF) is a defect of the aortic wall in the area above the right coronary cusp, where it separates aorta and right ventricular outflow-tract. Often, it is due to trauma or infective endocarditis. We report an occasional finding in an old woman without these causes.

CASE REPORT

A 73-year-old woman was referred for acute heart failure to the emergency department. Physical examination revealed a 4/6 continuous cardiac murmur in the aortic region. Previous chest trauma, history of angina, and acute infectious processes were excluded.

A two-dimensional (2D) echocardiography revealed normal left ventricular ejection fraction, moderate dilatation of right ventricle (RV), moderate dilatation of pulmonary artery, and an aorto-RV fistula (RVF) extending from the right sinus of Valsalva into the RV outflow tract (RVOT). Aortic and pulmonary valves were tricuspid, and there were no signs of other congenital anomalies. 2D color Doppler revealed severe tricuspid regurgitation and a significant left-to-right shunt from the aorta into RVOT (Qp/Qs = 2.2).

A 2D/3D transesophageal echocardiogram [Figure 1a, b and d] and a chest-computed tomography (CT) scan confirmed the isolated aorto-RVF [Figure 1c] with normal sizes of aortic root and ascending aorta [Figure 1], Video.

Figure 1

Multimodal evaluation of congenital aorto-right ventricular fistula through three-dimensional transesophageal echocardiography (a), two-dimensional transesophageal echocardiography (b), and chest-computed tomography (c); two-dimensional color Doppler transesophageal echocardiography showing severe tricuspid regurgitation and a significant left-to-right shunt from the aorta into the right ventricular outflow tract (d)

Cardiac catheterization showed severe pulmonary hypertension (pulmonary artery pressure = 80 mmHg, increased total pulmonary vascular resistance = 605 and normal total systemic resistance = 1015 dynes × s/cm5 (n.v. respectively <250 and 800–1200 dynes × s/cm5) and coronary angiography nonobstructive coronary disease.

Aorto-RVF is a very rare entity. It can be either congenital[12] or acquired; it has been described secondary to endocarditis,[3] Valsalva aneurysm rupture,[4] chest trauma, or aortic dissection.[5]

We report a late clinical presentation of a congenital aorto-RVF associated with pulmonary hypertension. Although the transthoracic echocardiogram is the primary diagnostic tool, 3D transesophageal echocardiogram and cardiac CT can provide important anatomical and functional information to exclude additional congenital anomalies.[6]

In these patients, the first therapeutic approach is to handle with the right-sided heart failure. The management of it requires simultaneous execution of multiple strategies to optimize RV preload, contractility, and afterload, while maintaining a favorable balance between the right- and left-sided circulations. In these cases, the RV output is impaired because of a higher preload due to LV-RV shunt and a concomitant high RV afterload due to pulmonary hypertension. In the case reported, we used diuretic therapy (furosemide) to reduce excessive volume overload and RV dilatation and O2 therapy maintaining oxygen saturations of ≥94% to prevent hypoxia which causes pulmonary vasoconstriction. The patient received further oral macitentan (10 mg once a day), an endothelin receptor antagonist used off-label based on the evidence of reversibility of pulmonary vascular resistance during cardiac catheterization. During the hospitalization after a heart team evaluation, surgical treatment was excluded due to high surgical risk and clinical response to medical therapy with improvement of symptoms and decrease of pulmonary hypertension.

Surgical and interventional therapies are indicated for patients with potentially reversible RVF unresponsive to or intolerant of medical therapy or for those with disease progression despite maximal medical therapy.

Surgical closure is the treatment of choice; however, transcatheter closure has been attempted with relatively acceptable results in residual or recurrent tunnel and aortic valve insufficiency after surgical repair.[7] No data in literature on the percutaneous closure of congenital defects in the adults are present.

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Conflicts of interest

There are no conflicts of interest.