Has invasive management for acute coronary syndromes become more ‘risk-appropriate’: pooled results of five Australian registries

Background: Despite being recommended in acute coronary syndrome (ACS) guidelines, the use of invasive management within specific risk groups continues to be debated. This study examines the change in the use of invasive management in ACS by patient risk and the associated change in mortality within Australia over the last 17 years. Methods: Pooled cohorts derived from five ACS registries (ACACIA, CONCORDANCE, GRACE, Snapshot-ACS, and Predict) spanned from 1999 to 2015. After excluding patients without a final diagnosis of ACS (n = 4460), enrolled outside Australia (n = 1477) and without an enrolling year (n = 4), 15 912 patients were analysed. Data was stratified across three time periods (1999-2004, 2005-2009, and 2010-2015) using clinical risk characteristics (age, ACS diagnosis, biomarker elevation, and GRACE score) to monitor change in practice. Results: Over the 17-year period, the use of invasive management increased (4073/6863 (59.3%) cases [1999-2009] vs. 6670/8706 (76.6%) cases [2010-2015]). Invasive management accounted for improvements in mortality in intermediate- and high-risk groups (intermediate risk: 14% (95% CI 1-66%) [1999-2009] vs. 49% (95% CI 2-59%) [2010-2015]; high risk: 24% (95% CI 6-42%) [1999-2009] vs. 48% (95% CI 19-76%) [2010-2015]). Patients receiving no angiography compared with interventional management had worse outcomes (1999-2004 1.55 HR [95% CI 1.36-1.80], P < 0.0001 vs. 2010-2015 1.90 HR [95% CI 1.45-2.51], P < 0.0001). Conclusions: Clinical practice in ACS has changed over the last 17 years with positive outcomes seen with invasive management among high-risk patients. Unfortunately, a considerable burden of mortality remains in patients managed medically, highlighting a need for more focused strategies that improve care and outcomes in this group.