O-147 - EPIDEMIOLOGY AND OUTCOMES OF AORTIC DISSECTION IN NEW ZEALAND

TOPIC:
Thoraco-abdominal Aortic Disease
AUTHORS:
Xu W. (University of Auckland ~ Auckland ~ New Zealand) , Bernau O. (University of Auckland ~ Auckland ~ New Zealand) , Haran C. (University of Auckland ~ Auckland ~ New Zealand) , Mani K. (University of Uppsala ~ Uppsala ~ Sweden) , Pitama S. (University of Otago ~ Dunedin ~ New Zealand) , Manar K. (Waikato Hospital ~ Hamilton ~ New Zealand)
Introduction:
Aortic dissection is a lethal condition with high mortality. Data from international studies suggests that incidence is increasing. This study aimed to evaluate the incidence and 30-day mortality of acute aortic dissection (AD) in Aotearoa New Zealand.
Methods:
A national population-based study of patients presenting with an index admission of acute AD from 2010-2020 in Aotearoa New Zealand was conducted. Data were collected from Ministry of Health Minimum Dataset and the Australasian Vascular Audit, a prospectively maintained binational audit of all vascular procedures. Demographic factors including ethnicity, deprivation, and comorbidities were collected from ICD-10 coding. Classification of AD was determined from relevant procedure codes. The primary outcome was 30-day mortality.
Results:
Out of 3043 events with a diagnosis code for aortic dissection between 2010 and 2020, 1533 patients presented with an index admission for AD and were included. In total, 621 (46.1%) patients had surgical management of Type A dissections, 152 patients had open or endovascular surgery for Type B dissections, 629 (29.5%) patients had medical management of their dissection and 135 (13.3%) of patients died within 24 hours of presentation. The most common comorbidity recorded was hypertension (53.6%). Māori patients presented younger with AD (57.5 vs 68.2 years [non-Māori], p<0.001) but had similar 30-day mortality rates (22.4% vs 25.2% [non-Māori], p=0.400). Patients with higher indices of socioeconomic deprivation also presented at a younger age (lowest deprivation index quintile 68.8 years vs highest deprivation quintile 66.4 years, p <0.001) but had similar 30-day mortality rates (lowest deprivation index quintile 24.4% vs highest deprivation quintile 24.0%, p = 0.667) Over the 11-year period, there was an increasing incidence of AD (2010=98 cases, 2020=131, Mann-Kendall trend-test p= 0.003) but no change in 30-day mortality rate (2010: 16.3%, 2020: 21.4%, trend-test p=0.755). Thirty-day mortality remains high postoperatively at 19.5% for surgically managed Type A patients, and 13.3% for surgically managed Type B patients.
Conclusion:
Despite technological advances, there remains a significant preoperative and postoperative mortality rate in acute AD, with many patients dying before surgical intervention. An increasing incidence was observed over the study period in Aotearoa New Zealand, consistent with observations internationally.