Unique characteristics of the type B aortic dissection patients with malperfusion in the Vascular Quality Initiative

Objective: Type B aortic dissection (TBAD) complicated by malperfusion carries high morbidity and mortality. The present study was undertaken to compare the characteristics of malperfusion and uncomplicated cohorts and to evaluate the long-term differences in survival using a granular, national registry. Methods: Patients with TBAD entered into the thoracic endovascular aortic repair/complex endovascular aortic repair module of the Vascular Quality Initiative from 2010 to 2019 were included. The demographic, radiographic, operative, postoperative, in-hospital, and long-term reintervention data were compared between the malperfusion and uncomplicated TBAD groups using t tests and chi(2) analysis, as appropriate. Overall survival was compared using Cox regression to generate survival curves. Results: Of the 2820 included patients, 2267 had uncomplicated TBAD and 553 had malperfusion. The patients with malperfusion were younger (age, 55.8 vs 61.2 years; P<.001), were more often male (79.7% vs 68.1%; P<.001), had a higher preoperative creatinine (1.8 vs 1.1 mg/dL; P<.001), had more often presented with an American Society of Anesthesiologists class of 4 or 5 (81.9% vs 58.4%; P<.001), and had more often presented with urgent status (77.4% vs 32.8%; P<.001). In contrast, the uncomplicated TBAD group had had more medical comorbidities, including coronary artery disease and chronic obstructive pulmonary disease, and a larger aortic diameter (4.0 cm vs 4.9 cm; P<.001). The malperfusion group more frequently had proximal zones of disease in zones 0 to 2 (38.6% vs 31.5%; P=.002) and distal zones of disease in zones 9 and above (78.7% vs 46.2%; P<.001), with a greater number of aortic zones traversed (7.7 vs 5.1; P<.001) and a greater frequency of dissection extension into branch vessels (61.8% vs 23.1%; P<.001). Patients with malperfusion also exhibited greater case complexity, with a greater need for branch vessel stenting and longer procedure times. The overall incidence of postoperative complications was greater in the malperfusion group (39.4% vs 17.1%; P<.001) and included a greater rate of spinal cord ischemia (6.3% vs 2.2%; P<.001), acute kidney injury (10.4% vs 0.9%; P<.001), and in-hospital mortality (11.6% vs 5.6%; P<.001). In-hospital reintervention was also greater for the malperfusion patients (14.5% vs 7.4%; P<.001), although the incidence of long-term reinterventions was similar between the two groups (8.7% vs 9.7%; P=.548). A proximal zone of disease in zone 0 to 2 was associated with decreased survival. In contrast, a distal zone of disease in 9 and above, in-hospital reintervention, and long-term follow-up were associated with increased survival. Despite these differences, long-term survival did not differ between the malperfusion and uncomplicated groups (P=.320.) Conclusions: Patients presenting with TBAD and malperfusion represent a unique cohort. Despite the greater need for branch vessel stenting and in-hospital reintervention, they had similar long-term reintervention rates and survival compared with those with uncomplicated TBAD. These data lend insight with regard to the observed differences between uncomplicated and malperfusion TBAD.