Study to Evaluate the Clinical Performance of the Valiant Thoracic Stent Graft With the Captivia Delivery System (Valiant Captivia) for the Treatment of Acute, Complicated Type B Aortic Dissections

Inclusion criteria

• Subject signed an informed consent.
• Subject is at least 18 years old.
• Subject has an acute, complicated Type B aortic dissection with evidence of at least one of the following:
• Malperfusion (visceral, renal, spinal cord and/or lower limb ischemia)
• Visceral ischemia measured by either radiographic or clinical evidence.
• Renal ischemia measured by either radiographic or clinical evidence.
• Spinal cord ischemia measured by either radiographic or clinical evidence.
• Lower limb ischemia measured by either radiographic or clinical evidence.
• Rupture - Measured by radiographic or clinical evidence.
• Subject is hemodynamically stable.
• Subject's anatomy must meet all of the following anatomical criteria:

Proximal landing zone aortic diameter must be between 20 mm and 44 mm;

• Centerline distance from distal margin of left CCA or in cases of bovine anatomy, innominate artery, to start of most proximal tear must be ≥ 20 mm;
• Subject has patent iliac or femoral arteries or can tolerate an iliac conduit that allows endovascular access to the dissection site with the delivery system of the appropriate sized device.
• Thoracic aortic dissection is confirmed, at a minimum, by diagnostic contrast-enhanced computerized tomography angiogram (CTA) with 3-D reconstruction, and/or contrast enhanced magnetic resonance angiogram (MRA) obtained prior to the implant procedure.

Exclusion criteria

• Planned placement of the COVERED portion of the stent graft over the left carotid artery, or the celiac trunk.
• Subject has systemic infection.
• Subject is pregnant.
• Subject has received a previous stent or stent graft or previous surgical repair in the DTA.
• Subject has had a cerebral vascular accident (CVA) within 2 months.
• Subject has a history of bleeding diathesis, coagulopathy, or refuses blood transfusion.
• Subject has a history of Marfan Syndrome or other connective tissue disorder.
• Subject is currently participating in an investigational drug or device clinical trial which would interfere with the endpoints and follow-ups of this study.
• Subject has a known allergy or intolerance to the device components.
• Subject has a known hypersensitivity or contraindication to anticoagulants or contrast media, which is not amenable to pre-treatment.
• Subject has a co-morbidity causing expected survival to be less than 1 year.