Imaging description

The sinuses of Valsalva are focal expansions forming the walls of the aortic root. Sinus of Vasalva aneurysm (SVA) is a rare congenital anomaly with involvement of the right sinus in 65– 85% of instances, and less commonly originating from noncoronary (10–30%) and left sinuses (< 5%). Most SVA are congenital due to deficiency of the normal elastic tissue and abnormal development of the bulbus cordis. Acquired SVA can be seen with infective endocarditis, trauma, tuberculosis, and Behçet disease. Up to 21% of reported cases of SVA are clinically asymptomatic, and may be incidentally found at necropsy or during a diagnostic test for evaluation of unrelated non-cardiac or cardiac abnormalities. SVA are found in association with ventricular septal defects in 30–60% of patients. SVA can be identified on all modalities used for imaging the heart and aorta including catheter angiography, echocardiography, multidetector computed tomography (MDCT) and cardiac magnetic resonance (CMR). Currently transthoracic followed by transesophageal echocardiography is recommended for the initial assessment of both ruptured or nonruptured SVA, as they offer advantage in color flow and spectral Doppler to demonstrate the presence and direction of turbulent jets at the point of rupture. MDCT and CMR generate high-resolution multiplanar images to facilitate three-dimensional visualization and provide imaging of the coronary arteries, which is useful when surgical correction is being considered. On cardiac MRI, sinus of Valsalva aneurysms manifest as thin-walled outpouchings that are contiguous with the aortic root on sequential slices. Rupture can be identified by a turbulent flow jet from the sinus into the adjacent cardiac chamber on cine bright blood images. Large SVA can project into the right atrium and mimic an atrial mass, particularly if thrombosed (Figures 19.1 and 19.2). Partial or complete thrombosis is often seen with SVA due to blood stasis.

Importance

SVA may mimic a right-sided cardiac mass, particularly if thrombosed, which could lead to incorrect diagnosis and may alter surgical planning.