Coarctation, PAPVR

Demonstrated is a bicuspid aortic valve and history of coarctation repair within the first week of life by end to end anastomosis. MRI obtained for evaluation of distal arch.

MRI findings:
• PAPVR of left upper lobe to innominate vein: Qp:Qs of 1.4:1
• Mild residual narrowing of second transverse segment of the aortic arch.
• Moderate post-stenotic dilation of aorta

MRI images obtained at end-systole due to tachycardic heart rate during exam.
RV End-systolic volume is 36.3 ml.
LV End-systolic volume is 30.06 ml.

MRI methods:
A GE 1.5T HDxt system was used for the 3D HEART sequence which used a 3D respiratory-navigated balanced SSFP (steady state free precession) multi-slab sequence with T2 preparation that provides whole heart coverage with high contrast-to-noise ratio between vessels and myocardium. Due to the relatively fast heart rate of 122 bpm, the fat saturation was turned off to decrease the time needed for the prepatory pulse brining the acquisition window earlier into the cardiac cycle so that it could be centered on the quiescent stage of end systole. The sequence was run with the following parameters: TR 3.4, TE 1.4, Freq 224, Phase 160, RR 8, and fat sat off.

Learning:
The MRI identified previously un-diagnosed partial anomalous pulmonary venous return. However, the Qp:Qs fell within acceptable left to right shunting of < 1.5:1 and there was insignificant RV, RA enlargement. The MRI evaluation of the coarctation repair revealed a good repair with only mild narrowing, which appeared more severe by echo due to the post-stenotic dilation. 

Disclaimer:
The available model has been validated to demonstrate the case’s pathologic features on a Z450 3D printer, (3DSystems, Circle Rock Hill, South Carolina)(or other printer as appropriate).  While the mask applied to the original DICOM images accurately represents the anatomic features, some anatomic detail may be lost due to thin walled structures or inadequate supporting architecture; while other anatomic detail may be added due to similar limitations resulting in bleeding of modeling materials into small negative spaces. However, intracardiac structures, relationships, and pathologic features represent anatomic findings to scale and in high detail.