Case Study | CARDIAC IMAGING
Ramiah Rajesh Kannan,
MD, DNB, PDCC
is Associate Professor at Amrita Institute
of Medical Sciences.
A 16-year-old patient presented with mild effort intolerance,
an SpO2 of 85%, and an uncertain diagnosis on previous
evaluations although truncus arteriosus was suspected.
Cine 2D FIESTA showed a large conoventricular VSD,
two balanced ventricles, and large pulmonary artery
overriding the VSD (Figure 5). Other Cine images showed
patent ductus arteriosus shunting right-to-left and sustaining
systemic blood flow, and juxta ductal coarctation. 3D MR
angiography revealed aortic atresia, hypoplastic ascending
aorta, reduced arborization and peripheral pruning of
bilateral lungs, more prominent in the left lung (Figure 6).
Phase contrast flow/time graphs of branch pulmonary
artery flows show rapid-deceleration pattern of elevated
pulmonary vascular resistance with left pulmonary blood
flow less than the right (Figure 7).
SVC flows IVC flows Systemic flow (Qs) = SVC + IVC LPA flows RPA flows Pulmonary flow (Qp) = RPA + LPA Qp:Qs
3. 4 liters/minute
2. 7 liters/minute
3. 7 liters/minute
6. 4 liters/minute
1.9 : 1
Based on MRI findings, the patient was correctly diagnosed
with hypoplastic ascending aorta with duct-dependent
systemic blood flow. Phase contrast flow study revealed
Qp:Qs of 1.9:1 with co-existing pulmonary vascular disease.
CMR also indicated that left pulmonary vascular resistance
is likely to be higher than the right.