EVOLVING SURGICAL TECHNIQUES AND IMPROVING OUTCOMES FOR AORTIC ARCH SURGERY IN CANADA

Abstract

BACKGROUND To explore evolving surgical techniques and outcomes for aortic arch surgery. METHODS AND RESULTS 2435 consecutive patients underwent aortic arch repair with hypothermic circulatory arrest between 2008 and 2018 in 12 institutions across Canada. Trends in patient characteristics, surgical techniques, and in-hospital outcomes including major morbidity or mortality (MMOM) were examined. From 2008-2018, age of patients (62.3yrs ± 13.2) and proportion of women (30.2%) undergoing arch surgery did not significantly change. Aortic diameters at operation decreased (2008: 58 ± 13mm, 2018: 53 ± 11mm; p < 0.01). Surgeons performed more valve-sparing root replacements (2008: 0%, 2018: 15%; p < 0.001) and fewer Bentall procedures (2008: 27%, 2018: 20%; p < 0.01). Total arch replacement rates were similar (p=0.18); however, elephant trunk (2008: 9.5%, 2018: 19%; p < 0.001) and frozen elephant trunk (2008: 3.1%, 2018: 15%; p < 0.001) repair rates have increased. Overtime, higher nadir temperatures (2008: 18[17-21]°C, 2018: 25[23-28]°C; p < 0.001), and more frequent antegrade cerebral perfusion (ACP) (2008: 61%, 2018: 83%; p < 0.001) were used. For elective cases, in-hospital mortality rates declined (2008: 6.8%, 2018: 1.2%; p= < 0.01), as did MMOM (2008: 24%, 2018: 13%; p < 0.001) and transfusion rates (2008: 61%, 2018: 41%; p < 0.001); but stroke rates remained constant (2008: 6.8%, 2018: 5.3% p=0.12).Outcomes remained the same over time for urgent or emergent cases. CONCLUSION Outcomes have improved over the last decade in Canada for elective aortic arch surgery, in the context of operating on smaller aortas, and more frequent use of moderate hypothermia and ACP. Further research is needed to improve stroke rates and outcomes in the emergency setting. To explore evolving surgical techniques and outcomes for aortic arch surgery. 2435 consecutive patients underwent aortic arch repair with hypothermic circulatory arrest between 2008 and 2018 in 12 institutions across Canada. Trends in patient characteristics, surgical techniques, and in-hospital outcomes including major morbidity or mortality (MMOM) were examined. From 2008-2018, age of patients (62.3yrs ± 13.2) and proportion of women (30.2%) undergoing arch surgery did not significantly change. Aortic diameters at operation decreased (2008: 58 ± 13mm, 2018: 53 ± 11mm; p < 0.01). Surgeons performed more valve-sparing root replacements (2008: 0%, 2018: 15%; p < 0.001) and fewer Bentall procedures (2008: 27%, 2018: 20%; p < 0.01). Total arch replacement rates were similar (p=0.18); however, elephant trunk (2008: 9.5%, 2018: 19%; p < 0.001) and frozen elephant trunk (2008: 3.1%, 2018: 15%; p < 0.001) repair rates have increased. Overtime, higher nadir temperatures (2008: 18[17-21]°C, 2018: 25[23-28]°C; p < 0.001), and more frequent antegrade cerebral perfusion (ACP) (2008: 61%, 2018: 83%; p < 0.001) were used. For elective cases, in-hospital mortality rates declined (2008: 6.8%, 2018: 1.2%; p= < 0.01), as did MMOM (2008: 24%, 2018: 13%; p < 0.001) and transfusion rates (2008: 61%, 2018: 41%; p < 0.001); but stroke rates remained constant (2008: 6.8%, 2018: 5.3% p=0.12).Outcomes remained the same over time for urgent or emergent cases. Outcomes have improved over the last decade in Canada for elective aortic arch surgery, in the context of operating on smaller aortas, and more frequent use of moderate hypothermia and ACP. Further research is needed to improve stroke rates and outcomes in the emergency setting.