Cardiac surgical outcomes in indigenous Australians: The Flinders Medical Centre registry

Background: The indigenous population of Australia experience high rates of premature coronary artery and heart valve disease, however outcomes following cardiac procedures have not been well described .We studied 30-day and long-term outcomes of indigenous patients following cardiac surgery.

Patients and methods: We prospectively collected clinical, operative and post-operative event data for consecutive indigenous (n = 283) and non-indigenous (n = 2351) patients undergoing cardiac surgery at Flinders Medical Centre between January 2000 and December 2005. Post discharge mortality was evaluated by a search of the National Death Index.

Results: Indigenous patients were younger (47 ± 14 years versus 65 ± 12 years, p < 0.001), more likely to be female (40% versus 28%, p = 0.001), have diabetes (41% versus 28%, p = 0.001), and renal dysfunction (3% versus 1%, p = 0.009). Single or double valve procedures were more commonly performed in indigenous patients (43% versus 21%, p < 0.001). The 30-day mortality for indigenous patients was 3% versus 1% for non-indigenous (odds ratio 1.9; 95% CI: 0.8–4.3). When adjusted for age less than 55 years, there was significant excess 30-day mortality in indigenous patients (odd ratio 8.6; 95% CI: 1.6–85.4). At a median follow up of 44 months (range 26–64), death occurred in 293 patients (11%), with indigenous n = 36 (13%), and non-indigenous n = 257 (11%). Adjusted for age less than 55, late mortality was significantly higher in the indigenous n = 26 (10%) than the non-indigenous cohort n = 32 (1%), p = 0.002.

Conclusions: Age adjusted 30-day and late mortality is higher in indigenous patients undergoing cardiac surgery in Australia. The burden of cardiovascular disease appears to be experienced two decades earlier than among non-indigenous patients.