Ischemic Complications

On CT, the finding of a filiform true lumen and a large false lumen suggests one of the most dreaded complications of aortic dissection—namely, compression of the true lumen by an expanded false lumen55-58 (Figure 5.18). Compression may be static or dynamic, depending on whether the expanded false lumen is thrombosed or perfused. Branch vessel occlusion, occlusion of the distal aorta, and subsequent ischemia are the consequences. Accordingly, impairment of branch vessel perfusion can be static, dynamic, or both59-61. Static impairment has to be assumed if

• The dissection flap extends into the branch vessel with subsequent narrowing or occlusion of the branch (Figure 5.19),

• The branch vessel origins from a thrombosed false lumen, or

Aortic Dissection Static Occlusion

Figure 5.18. Axial contrast-enhanced CT images of a thrombosed false lumen (intramural hematoma), which compresses the true lumen at the level of the renal artery origins: (a) perfusion of the right renal artery (arrow) from the true lumen is maintained; (b) left renal artery origin is compressed (arrow), (note delayed enhancement of the left kidney consistent with impaired perfusion).

Figure 5.18. Axial contrast-enhanced CT images of a thrombosed false lumen (intramural hematoma), which compresses the true lumen at the level of the renal artery origins: (a) perfusion of the right renal artery (arrow) from the true lumen is maintained; (b) left renal artery origin is compressed (arrow), (note delayed enhancement of the left kidney consistent with impaired perfusion).

Figure 5.19. Axial contrast-enhanced CT image of aortic dissection with largely thrombosed false lumen (black arrow) and extension of the dissection into the right renal artery. The white arrow indicates the dissection flap in the right renal artery. There was diminished perfusion of the right kidney (not shown).

Figure 5.19. Axial contrast-enhanced CT image of aortic dissection with largely thrombosed false lumen (black arrow) and extension of the dissection into the right renal artery. The white arrow indicates the dissection flap in the right renal artery. There was diminished perfusion of the right kidney (not shown).

• The true lumen is compressed by an expanded and thrombosed false lumen (Figure 5.18b).

Dynamic impairment of branch vessel perfusion can occur if the dissection flap is located close to the origin of the branch vessel and covers its origin

Figure 5.20. Axial contrast-enhanced image of traumatic type B dissection with rupture in patient with motor vehicle accident. Black arrow indicates dissection flap in the descending thoracic aorta. High attenuation of the mediastinum is consistent with hemo-mediastinum (white arrow). Black arrowhead indicates high attenuation pleural fluid consistent with hemothorax. White arrowhead indicates chest tube.

Figure 5.20. Axial contrast-enhanced image of traumatic type B dissection with rupture in patient with motor vehicle accident. Black arrow indicates dissection flap in the descending thoracic aorta. High attenuation of the mediastinum is consistent with hemo-mediastinum (white arrow). Black arrowhead indicates high attenuation pleural fluid consistent with hemothorax. White arrowhead indicates chest tube.

like a curtain59. This may be the case if the true lumen is compressed by an expanded but perfused false lumen.

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  • lavinia
    What are ischemic complications of aotric dissection?
    8 years ago

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