IJCS | Volume 31, Nº5, September / October 2018

475 Oliveira et al. Mortality and survival in aortic arch surgeries Int J Cardiovasc Sci. 2018;31(5)466-482 Original Article protection was also established by selective cerebral perfusion. In the study by Tang et al., 13 a review of the contemporary practice in total arch replacement by using the trifurcated graft technique was performed. The authors concluded that unilateral and bilateral antegrade cerebral perfusion and profound hypothermia can be performed without adding significant complexity to the procedure while conferringmaximal cerebral protection. Surgical strategy for aortic arch reconstruction described in groupA includes axillary artery cannulation. Although femoral arterial cannulation is considered a routine procedure, Benedetto et al. 14 reported that there is a growing perception that this technique, by reversing the flow in the thoracoabdominal aorta, may increase the risk of retrograde brain embolization, dissection and organ malperfusion in type A aortic dissection. Axillary artery cannulation shows better surgery outcomes by allowing antegrade outflow. In this meta-analysis, acute aortic dissection was demonstrated to be superior to femoral artery cannulation in reducing in-hospital mortality and the incidence of permanent neurological deficit in patients operated for type A acute aortic dissection. Characteristics of the study population are similar to those of other groups 15 studied for operative outcomes of surgical approaches of aortic arch diseases, including the high prevalence of the most common risk factors. In group A, there were patients with history of neurologic events (ischemic or hemorrhagic), representing 10.7%and 7.4% of total study population, respectively. In both groups, there were patients who were submitted to surgical procedure despite suffering a stroke in the preoperative period, which until a few years ago, would be considered contraindication to surgery. However, this fact started to change by the study byMost et al. 16 The authors retrospectively studied 53 patients with recent neurological deficit (whichwere considered a contraindication for surgery due to poor prognosis) who received surgical repair for acute aortic dissection type A between 2005 and 2012. They showed that more than half of them recovered fromsurgerywithout neurological sequelae and concluded that patients with acute type A aortic dissection and neurological deficit before surgery should not be excluded from emergency surgery. In group A, 24.1% of patients underwent elective surgery, 58.6% urgent and 17.2% emergent surgery. Aortic dissection was the predominant procedure among these patients, similar to the study by Martín et al. 15 However, in this study, 93% of patients underwent emergent surgery and 7% urgent surgery, and positive outcomes were observed even in patients in coma. 16 Early diagnosis and therapy for acute aortic dissection is crucial for postoperative outcome. While less significant improvements were associated with surgical interventions performed more than 9 hours of symptom onset, patients who underwent surgery less than 5 hours of symptom onset showed more favorable outcomes. It is of note that postoperative drainage volume within the first 24 hours was associated with possible postoperative bleeding. Mean drainage volume was 468 mL and 375 mL in groups A and B, respectively (no statistical significance). In Miana et al., 17 mean 24- hour bleeding volume was 610 ± 500 mL in a group of 411 patients undergoing surgery for acquired heart diseases. In the subgroup of patients who underwent aortic surgery, mean bleeding volume was 765 ± 770 mL among those at higher risk of bleeding and 604 ± 479 mL among those at lower bleeding risk. Although surgical strategy performed in group A proposes amore careful approach of hemostasis, a greater bleeding volume was observed in these patients. This may be explained by the longer ECC time and higher rates of emergent surgeries, which are independent risk factors for bleeding. 17 Also, in this group, most patients underwent surgical repair of acute aortic dissection. Among postoperative neurological complications, hemorrhagic stroke occurred in 1 patient (3.4%) in group A and 1 patient (1.3%) in group B. In a group of 98 patients undergoing surgery for type A aortic dissection, the incidence of permanent stroke was 9%. 15 In a recent meta-analysis, 7.3% of patients undergoing antegrade cerebral perfusion and moderate hypothermia had permanent neurological dysfunction. 18 In the study by Kazui et al. 9 the incidence of temporary and permanent neurological dysfunction was 4.2% and 2.4%, respectively. Hagl et al. 19 examined 717 patients who survived aortic arch and ascending aorta operations through median sternotomy for risk factors for stroke. When all patients with total cerebral protection time between 40 and 80 minutes were examined, the method of cerebral protection did not influence the occurrence of stroke; however, antegrade cerebral perfusion resulted in a significant reduction in the incidence of temporary neurological dysfunction (p = 0.05; OR 0.3). Postoperative AMI was present in 10.3% of patients in group A and in 1.3% of patients in group B (p = 0.025).