EndoVascular Aortic Dissection Early vs Delayed

Inclusion Criteria: * Acute (2-14 days) high-risk type B aortic dissection. * Completion of thoracoabdominal aortic CTA before enrollment. * Ability to understand the study objectives and voluntarily participate, with signed informed consent from the patient or their legal representative. * Willingness and ability to comply with follow-up visits and study protocols. Exclusion Criteria: * Acute complicated type B aortic dissection. * Traumatic dissection or penetrating aortic ulcer. * Connective tissue diseases (e.g., Marfan syndrome, Loeys-Dietz syndrome, Ehlers-Danlos syndrome). * Pregnancy, women of childbearing potential, or breastfeeding. * Uncontrolled active infection or active vasculitis. * Unsuitable access vessels or infection at the access site. * Endovascular repair requiring ≥2 branch reconstructions. * Prior aortic surgery (open or endovascular). * Life expectancy \<2 years. * Myocardial infarction or cerebrovascular accident within 4 weeks before enrollment. * Severe gastrointestinal bleeding, major surgery, myocardial infarction, or uncorrected coagulation dysfunction within 6 weeks before enrollment. * Other conditions deemed by the investigator to compromise the patient's medical interests or unlikely adherence to the study protocol.