Incidence and Outcomes of Abdominal Aortic Aneurysm Repair in New Zealand from 2001 to 2021

Abstract

Purpose: The burden of abdominal aortic aneurysms (AAA) has changed in the last 20 years but is still considered to be a major cause of cardiovascular mortality. The introduction of endovascular aortic repair (EVAR) and improved peri-operative care has resulted in a steady improvement in both outcomes and long-term survival. The objective of this study was to identify the burden of AAA disease by analysing AAA-related hospitalisations and deaths. Methodology: All AAA-related hospitalisations in NZ from January 2001 to December 2021 were identified from the National Minimum Dataset, and mortality data were obtained from the NZ Mortality Collection dataset from January 2001 to December 2018. Data was analysed for patient characteristics including deprivation index, repair methods and 30-day outcomes. Results: From 2001 to 2021, 14,436 patients with an intact AAA were identified with a mean age of 75.1 years (SD 9.7 years), and 4100 (28%) were females. From 2001 to 2018, there were 5000 ruptured AAA with a mean age of 77.8 (SD 9.4), and 1676 (33%) were females. The rate of hospitalisations related to AAA has decreased from 43.7 per 100,000 in 2001 to 15.4 per 100,000 in 2018. There was a higher proportion of rupture AAA in patients living in more deprived areas. The use of EVAR for intact AAA repair has increased from 18.1% in 2001 to 64.3% in 2021. The proportion of octogenarians undergoing intact AAA repair has increased from 16.2% in 2001 to 28.4% in 2021. The 30-day mortality for intact AAA repair has declined from 5.8% in 2001 to 1.7% in 2021; however, it has remained unchanged for ruptured AAA repair at 31.6% across the same period. Conclusions: This study highlights that the incidence of AAA has declined in the last two decades. The mortality has improved for patients who had a planned repair. Understanding the contemporary burden of AAA is paramount to improve access to health, reduce variation in outcomes and promote surgical quality improvement.

Propensity score analysis demonstrates no long term survival benefit from contemporary endovascular aneurysm repair compared to open in Aotearoa New Zealand

“…In addition, the median age of participants in the EVAR‐1 trial and DREAM trials with 6 years follow up was 74 and 70 years old, respectively. Whereas in this study the median age was 74 and the proportion of octogenarians in NZ undergoing intact AAA repair has increased from 16.2% in 2001 to 28.4% in 2021 21 …”

“…The higher utilization of EVAR compared to OAR repairs in this analysis is reflective of the paradigm shift. In the last 20 years, there has been a significant increase in EVAR usage in NZ from 18.1% in 2001 to 64.3% in 2021 which has coincided with a decline in 30 day mortality following intact AAA repair which has been observed elsewhere and has been predominantly related to the rise in EVAR usage 21 . A systematic review of the randomized trials comparing EVAR versus OAR demonstrated that EVAR had an early, significant perioperative mortality advantage of 1.3% compared to 4.7% respectively (OR 0.36, 95% CI 0.21–0.61, P < 0.001) 22 .…”

Trends in AAA Repair in Australia Over Twenty Years

“…6,[13][14][15] New Zealand noted a similar transition in 2011, five years after Australia. 16 Additionally, Japan and Finland joined this trend in 2013. 17,18 This early uptake and proliferation of EVAR in Australia can likely be attributed to the pioneering role that Australian vascular surgeons played in the innovation of stent graft technology.…”