Malperfusion syndromes in aortic dissections

Abstract

Aortic dissection remains a challenging clinical scenario, especially when complicated by peripheral malperfusion. Improvements in medical imaging have furthered understanding of the pathophysiology of malperfusion events in association with aortic dissection, including the elucidation of different mechanisms of branch vessel obstruction. Despite these advances, malperfusion syndrome remains a deadly entity with significant mortality. This review presents the latest knowledge regarding the pathogenesis of aortic dissection complicated by malperfusion syndrome, and discusses the diagnostic and therapeutic guidelines for management of this vicious entity.

Keywords: aortic diseases; minimally invasive; practice guidelines; stents; surgical procedures.

Figure 1

Frequency of distribution and symptoms associated with descending aortic dissection based on studies by MGH and IRAD (19, 55). Reprinted with permission.

Figure 2

A. Static dissection seen as protrusion of the intimal flap into the ostium of the affected branch vessel causes subsequent thrombosis of the branch vessel with resulting perfusion impairments. B. Dynamic dissection demonstrates protrusion into the ostium of a branch vessel is the most common cause of malperfusion syndrome and results in variable symptoms given the dynamic nature of the occlusion.

Figure 3

Ultrasound findings of renal artery malperfusion is manifested as A. increased proximal peak systolic velocities and B. absence of diastolic flow.

Figure 4

A. Aortic angiography of proximal descending aortic dissection with aortic narrowing due to dissection flap (solid arrow). B. Successful deployment of self-expanding stent into the proximal descending aorta for the management of a descending thoracic dissection. The takeoff of the left subclavian artery can be seen at the second position marker (outlined arrow).

Figure 5

Completion angiogram after deployment of self-expanding stent into the proximal renal artery for management of dissection involving the left renal artery revealing unimpaired blood flow.

Figure 6

Suggested guidelines for management of complicated type B aortic dissection with evidence of renal, mesenteric and extremity segment malperfusion.