Abstract DP236: Temporal Trends in Stroke After Cardiac Surgery: 10-Year Analysis of 137,720 Patients from the Australian and New Zealand Society of Cardiothoracic Surgery (ANZSCTS) Adult Cardiac Surgical Database.

Introduction: Permanent stroke after cardiac surgery remains a major source of morbidity and mortality. Large-scale, contemporary data describing long-term incidence, risk factors, and outcomes in Australia and New Zealand are limited. This study examined the incidence and evolving risk profiles over the past decade using a comprehensive registry. Methods: Adults undergoing cardiac surgery (2014-2023) in the Australian and New Zealand Society of Cardiothoracic Surgery (ANZSCTS) Adult Cardiac Surgical Database were analysed. This bi-national clinical registry prospectively captures preoperative, intraoperative, and outcome data from >95% of cardiac surgeries in Australian and New Zealand. Permanent stroke was defined as a new neurological deficit persisting >72 hours. Trends were tested with the Cochran-Armitage test; multivariable logistic regression identified independent predictors; calendar year was excluded as a covariate to allow mechanistic interpretation of changes in predictor prevalence over time. Results: Among 137,720 patients, permanent stroke occurred in 2,104 patients (1.53%). Incidence increased from 1.13% in 2014 to 1.43% in 2023 (+27% relative change, p-trend<0.001). Independent predictors were prior cerebrovascular disease (OR 2.01, 95% CI 1.80-2.25), urgent/emergent/salvage operative status (OR 2.01, 95% CI 1.82-2.05), complex procedures (combined CABG-valve or multi-valve operations; OR 1.36, 95% CI 1.31-1.42), hypertension (OR 1.23, 95% CI 1.10-1.37), male sex (OR 1.19, 95% CI 1.07-1.31), diabetes (OR 1.19, 95% CI 1.08-1.32), advancing age (OR 1.01 per year, 95% CI 1.01-1.02), and longer cardiopulmonary bypass time (OR 1.01 per 10 minutes, 95% CI 1.01-1.02). Smoking history and dialysis were not independently associated. The temporal increase attenuated after adjustment, consistetnt with case-mix shifts. Stroke was associated with worse outcomes: higher 30-day mortality (19.1% vs 1.4%,), lower liklihood of discharge home (22.9% vs 78.6%), and greater rehabilitation requirement (40.6% vs 9.6%). Conclusions: Permanent stroke incidence after cardiac surgery in Australia and New Zealand has risen over the last decade, largely explained by evolving patient complexity. Patiets with prior cerebrovascular disease and non-elective status are at highest risk. Findings support risk-stratified neuroprotection and perioperative strategies to minimise modifiable contributors in high-risk patients.