A more proximal landing zone is preferred for thoracic endovascular repair of acute type B aortic dissections

Thoracic endovascular aortic repair (TEVAR) has become first-line therapy for complicated acute type B aortic dissection (aTBAD). However, the strategy for optimal proximal landing zone remains to be determined. We compared early outcomes and late aortic-related adverse events in patients undergoing TEVAR for complicated aTBAD with endograft deployment in proximal landing zone 2 vs 3.

We performed a retrospective chart review of adult patients undergoing TEVAR for complicated aTBAD within 6 weeks of diagnosis from January 2008 to December 2018. We excluded patients with connective tissue disorders and prior type A repair. Patients were divided into landing zone 2 TEVAR (Z2T) and zone 3 TEVAR (Z3T) groups. Z2 patients were divided between left subclavian artery (LSA) revascularization (Z2R) vs LSA coverage without revascularization (Z2C). Groups were compared for the need for aortic reintervention within 36 months of initial admission and freedom from aortic-related adverse events and mortality (AREM), defined as the need for aortic reintervention, aortic-related death, or rupture.

Eighty-three patients underwent TEVAR for complicated aTBAD within a mean of 4.1 ± 7.8 days; 89.5% of patients had less than 2 cm of healthy proximal descending thoracic aorta. The landing zone was Z3T in 35 patients and 48 underwent Z2T: 10 Z2C and 38 Z2R. There were no differences between Z2T and Z3T in time from diagnosis to TEVAR, demographics, comorbidities, and diameter aortic measurements. The 30-day survival was 87.8%-89.5% for Z2R, 88.6% for Z3, and 80.0% for Z2C (P = .610). The postoperative spinal cord ischemia rate was 3.7%-2.7% for Z2R, 0% for Z3T, and 20.0% for Z2C (P = .012). The postoperative thoracic aortic rupture was 2.2% in Z2 and 0 in Z3. The need for aortic reintervention at 36 months after TEVAR was lower for Z2T (10.4%) vs Z3T (31.4%; P = .025). Freedom from AREM at 36 months was higher in Z2T vs Z3T (87.5% vs 68.6%; P = .048). The freedom from proximal reintervention was higher in Z2T (95.8%) compared with Z3T (80.0%; P = .019). Z3T deployment was predictive for AREM (odd ratio, 3.648; 95% confidence interval, 1.161-11.465; P = .027) and need for proximal reintervention (odds ratio, 5.542; 95% confidence interval, 1.062-28.927; P = .042).

Most patients with aTBAD have less than 2 cm of proximal healthy descending thoracic aorta. In patients treated for complicated aTBAD, Z2T is associated with a lower need for aortic reintervention and aortic-related adverse events than Z3T. Patients may benefit from a more aggressive proximal landing zone with similar perioperative morbidity when Z2T is done with LSA revascularization.