RESULTS
Between December 2017 and May 2020, 70 consecutive patients (mean age 62.7±10.6 years, 84% male) underwent FET for arch and thoracic aorta pathologies, 41 (58.6%) acute aortic dissections (AAD) and 29 (41.6%) chronic pathologies: ascending aorta/aortic arch aneurysm (An) in 19 (24.3%) and chronic type I dissection (CAD) in 10 (14.2%). The distributions of baseline characteristics for the overall population are presented in Table 1. Twelve (17.1%) patients had already undergone cardiac surgery. Fifteen AAD patients (36.5%) presented with peripheral malperfusion. There were no significant differences in terms of age, gender and other preoperative comorbidities between the groups. The only significant difference was previous cardiac surgery (redo) (4.9% in emergency group vs. 34.5% in elective group, P<0.01) Patients presenting in emergency setting had a higher incidence of malperfusion but this difference did not reach statistical significance.
No intraoperative deaths were recorded. Operative characteristics and their distributions among the two groups are showed in Table 2. Concomitant procedures were required in 36 (51.4%) patients: 12 (17.1%) coronary artery bypass grafting, 10 (14.3%) aortic valve replacement, 14 aortic root surgery such as 9 (12.9%) Florida sleeve procedures and 5 (7.1%) modified Bentall. There was a statistically significant difference between the two groups in terms of cardiopulmonary bypass time (212.9±42.7 minutes in the emergency group vs. 175.5±51.1 minutes in the elective group, P<0.01) and aortic cross clamp time (123.8±38.9 minutes in the emergency group vs. 87.1±31.9 in the elective group, P< 0.01). The mean deep hypothermic circulatory arrest time was 30.6±6 minutes and did not differ among the two groups.
Postoperative outcomes are summarized in Table 3. Thirty-day mortality was 10.0% (n=7) for the entire cohort of patients (12.1% in emergency vs. 6.8% in chronic settings, P=0.421). Cumulative in-hospital mortality was 14.2% (n=12, 17.1% in emergency vs. 10.3% in chronic settings, P=0.312). No differences were found in terms of postoperative CVA (mRS 5/6, 2.4% in the emergency group vs. 0% in the elective group, P=1), SCI with paraplegia (2.4% in the emergency group vs. 0% in the elective group, P=1) and AKI requiring hemodialysis (31.7% in the emergency group vs. 20.7% in the elective group, P=0.454). The incidence of respiratory failure requiring tracheostomy did not differ between the two groups (31.7% vs 24.1%, P=0.673).
The final multivariable Cox proportional hazard model showed that higher LVEF (HR, 0.93; 95% CI 0.88—0.99; P=0.03) was a protective factor for mid-term survival, while cerebral malperfusion at presentation (HR, 4.42; 95% CI, 1.19—16.33; P=0.03) and aortic cross-clamp time (HR, 1.01; 95% CI, 1—1.02; P=0.05) were found to be independent predictor factors affecting mid-term survival. Emergency surgery did not significantly impact on long-term survival (elective HR, 0.60; 95% CI, 0.21–1.7; P=0.33).
There were no aortic re-interventions in either group. Five patients with residual type B dissection underwent TEVAR successful completion of repair which was performed at least 6 weeks after the primary operation in order to reduce the spinal cord ischemia risk. There was no dSINE and no intraluminal thrombosis.
Median follow-up was 12.5 months (IQR 3.9—22.3). Overall survival for the entire cohort at 3 months, 6 months, 12 months and 24 months was 90% (95% CI, 83.2—97.3), 85.6% (95% CI, 77.7—94.3), 79.1% (95% CI, 69.9—89.5), 75.6% (95% CI, 65.8—86.9) and 73.5 (95% CI, 63.3—85.3), respectively (Figure 3). Survival rate by group were 85.2% vs. 86.1% at 3 months, 77.3% vs. 82.2% at 6 months, 71.7% vs. 82.2% at 12 months and 68.6% vs. 82.2% at 24 months, all emergency vs. elective, respectively (Figure 4).