Download Supravalvular Aortic Stenosis - Massachusetts General Hospital

JUNE 2011
ISSUE 38
Supravalvular Aortic Stenosis
Manavjot S. Sidhu, MD; Leif-Christopher Engel, MD; Vikram Venkatesh, MD;Ami Bhatt, MD; Brian B. Ghoshhajra, MD; MBA,
and Wilfred Mamuya MD, PhD
Clinical History
A 51-year-old woman with a history of supravalvular aortic
stenosis presented with new onset exertional dyspnea. Her
history included an aortotomy at the age of 5, and, at the
age of 45, a Ross procedure, including composite aortic
root replacement with a pulmonary homograft and pulmonic
valve replacement with a 23 mm pulmonary homograft.
She refused a cardiac MRI, citing severe claustrophobia
during a prior experience at another hospital.
Findings
Cardiac CT was performed for anatomic survey and
quantitative assessment of biventricular function. The exam
found residual post-surgical supravalvular aortic stenosis
with collaterals (Figure 1), post-surgical stenosis of the
pulmonic trunk (Figure 2), non-obstructive coronary artery
disease (CAD) without evidence of coronary anomalies
(Figure 3), and mild concentric left ventricular hypertrophy
with preserved biventricular systolic function (Figure 4).
The resting right ventricular (RV) ejection fraction was
47%, and the resting left ventricular (LV) ejection fraction
was 62%. The exam also showed close high apposition
of anterior mediastinal structures to the posterior midline
and left sternum, a finding of great significance for repeat
sternotomy planning.
Figure 1
Figure 2
Figure 3
Figure 4
Discussion
Although the primary uses for cardiac CT include anatomic
imaging of the chest and coronary arteries, dual-source
cardiac CT has superior temporal resolution that allows
functional imaging [1, 2]. When our patient refused
a cardiac MRI, cardiac CT provided the necessary
quantitative assessment of RV systolic function. The
total radiation dose for this comprehensive exam was 2.1
mSv. As the population of adults with congenital heart
disease grows, mechanisms to study the right ventricle will
become increasingly important.3D-transthoracic cardiac
ultrasound (TTE) has the ability to quantitatively assess
RV systolic function, but is not currently widely available
[3]. Cardiac MRI and CT provide anatomic and functional
assessment of biventricular function in these patients, in
addition to offering images for pre-operative planning
REFERENCES
Figure 1: Oblique maximum intensity projection image shows a 57% area luminal
narrowing supravalvular aortic stenosis (green arrow) and collateral vessels
secondary to supravalvular aortic stenosis (red arrow). [Ao = Aorta, RA= Right
Atrium].
Figure 2: Concurrent coronary CTA (C) shows a calcified plaque (white
arrowhead), excludes significant coronary anomalies and obstructive CAD, and
shows close apposition of anterior mediastinal structures to the posterior midline
and left sternum (blue arrowhead). [RCA= Right Coronary Artery, LM= Left Main
artery, LCx= Left Circumflex artery, LAD= Left Anterior Descending artery].
Figure 3: Short axis view of the main pulmonary artery trunk and the aorta
shows 47% luminal narrowing (white arrow) of the pulmonary artery. [PA=
pulmonary artery, Ao= Aorta].
Figure 4: Functional dataset from the retrospective acquisition reveals preserved
biventricular systolic function.
1. Quantification of global left ventricular function: comparison of multidetector computed tomography and magnetic resonance imaging.
A meta-analysis and review of the current literature. van der Vleuten PA et al. Acta Radiol. 2006; 47:1049-57.
2. Right ventricle function assessment by MDCT. Dupont MV et al. Am J Roentgenol. 2011; 196:77-86.
3. Normal values of right ventricular size and function by real-time three-dimensional echocardiography: comparison to cardiac magnetic
resonance imaging. Gopal AS et al. J Am Soc Echocardiogr 2007; 20:445-55.
Editors:
Suhny Abbara, MD, MGH Department of Radiology
Wilfred Mamuya, MD, PhD, MGH Division of Cardiology