702 Long-Term Survival and Predictors of Outcomes of Indigenous Northern Territorians Undergoing Primary and Re-Do Surgery for Rheumatic Heart Disease in Australia

Abstract

Rheumatic Heart Disease (RHD) is the leading cause of heart valve dysfunction among the Indigenous population of Australia. Factors that contribute to late postoperative mortality have not been previously studied in Australia. 342 RHD Indigenous patients from the Northern Territory of Australia undergoing their primary surgical procedure between 1997 and 2016 were identified. Pre- and postoperative data was collated using clinical information systems. Multivariable survival analyses were performed using Cox Proportional Hazards model. Early 30-day mortality was 2% (CI 0.5-3.5). Mean follow-up time was 8.2 years (2,784 patient years). 63.5% were female. Mean age of RHD diagnosis was 25 years, mean age at first surgery was 31.6 years. Mean time interval from date of first RHD diagnosis to first surgical intervention was 6.3 years. 22% (n=74) underwent redo surgery, among these 75%, 20% and 5% underwent one, two and three redo surgeries respectively. There was a total of 93 (27.2%) deaths. Actuarial Survival at 5, 10, 15 and 20 years was 89% 70% 58% and 52% respectively. Preoperative Pulmonary Hypertension (ePASP >50mmHg), Chronic Kidney Disease (eGFR <60) and Coronary Heart Disease were independent predictors of mortality regardless of type of surgery and number of valves operated on. Indigenous Australians have poor long-term survival following cardiac surgery for RHD despite their young age. This is at least in part attributed to co-morbid conditions. Significant effort is required to prevent this disease, enable early detection and enhance early access to surgery with close long term follow-up.