A Type B aortic dissection is a spontaneous, nontraumatic dissection involving the descending aorta.
Mechanisms of malperfusion may include:
(1) collapse of the arterial lumen
(2) extension of the dissection into branch arteies
Vascular territories that may be affected:
(1) renal arteries
(2) mesenteric arteries
(3) spinal arteries
(4) iliac arteries (affecting the lower extremities)
Untreated malperfusion is associated with significant morbidity and mortality. Endovascular interventions (such as TEVAR or thoracic endovascular aortic repair) can restore perfusion in many cases.
Predictors of worse outcome:
(1) female gender
(2) continued smoking status
(3) hypotension
(4) renal failure
(5) left subclavian artery (LSA) occlusion by the TEVAR graft
(6) more severe aortic disease
