The use of thoracic endovascular aortic repair (TEVAR) to treat patients with both uncomplicated and complicated acute type B aortic dissections (tB-Ad) continues to rise, yet there exists limited national data evaluating outcomes and predictors of adverse events. Therefore, we compared the presentation and clinical features of early TEVAR for complicated and uncomplicated aortic dissections as well as outcomes and survival following repair. We queried the Vascular Quality Improvement registry (2011-2022) for TEVAR cases for acute (<2 weeks) and subacute (2-12 weeks) tB-Ad, dichotomizing patients into uncomplicated vs complicated dissections. Complicated dissection was defined as presentation with visceral malperfusion, rupture, or rapidly increasing aortic size, with uncomplicated dissection including all other presentations. Outcomes included postoperative morbidity and mortality, thoracoabdominal life-altering events (TALE defined as a composite of stroke, death, dialysis, or paraplegia), and 3-year survival. Risk adjusted analyses were performed using logistic regression clustering by center and Cox proportional hazard regression. Among 1749 patients treated for acute and subacute tB-Ad, 775 (44%) presented with complicated dissections. Patients with complicated dissection were more likely to be male (70% vs 61%; P < .01) and older (61.3 vs 59.7 years; P < .02), with longer procedural time (150 minutes vs 115 minutes; P < .01). Complicated dissections had higher unadjusted rates of 30-day mortality (16% vs 4.4%; P < .01), spinal cord ischemia (11% vs 4.6%; P < .01), stroke/transient ischemic attack (8.9% vs 4.7%; P < .01), new dialysis (5.8% vs 1.2%; P < .01), TALE (31% vs 12%; P < .01), and higher reintervention during index hospitalization (21% vs 9.0%; P < .01). Furthermore, complicated dissections had lower 3-year survival (82% vs 72%; P < .01) (Figure). After adjustment, complicated dissection was independently associated with higher odds of 30-day mortality (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.6-3.4; P < .01) and postoperative complications (OR, 1.9; 95% CI, 1.5-2.4; P < .01). Factors associated with increased three-year mortality included emergency repair (hazard ratio [HR], 2.3; 95% CI, 1.5-3.4]; P < .01), preoperative dialysis (HR, 2.8; 95% CI, 1.7-4.7; P < .01), and coronary artery disease (HR, 1.7; 95% CI, 1.2-2.4; P < .01). These data present contemporary results of TEVAR for tB-Ad, showing excellent mortality and morbidity for both uncomplicated and complicated presentations as compared to prior reports of medical and operative therapy. In light of these findings, and the risk of late aortic-related mortality shown in the literature, early aggressive intervention with TEVAR remains a necessity for complicated presentation and should be strongly considered in patients with acute uncomplicated tB-Ad. Further analyses regarding optimal timing for TEVAR in patients with tB-Ad are warranted.