Evaluating trends in acute coronary syndrome (ACS) and invasive coronary procedures, including coronary angiography, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) can identify areas for improvement in clinical care and inform future health planning. This national data-linkage study reports trends in ACS hospitalisations and procedure rates in New Zealand between 2006 and 2016.

All adult ACS hospitalisations and associated angiography and revascularisation procedures were identified from hospital discharge codes. Crude and age-standardised ACS incidence and procedure rates were calculated for each calendar year.

Between 2006 and 2016 there were 188,264 ACS admissions. During this time, there was a steady decline in hospitalisation rates, from 685 to 424 per 100,000 per year. This decline was observed in both sexes and in all age groups. There were also significant increases in coronary angiography and revascularisation rates, from 29.8% to 54.3% and 20.6% to 37.3%, respectively, between 2006 and 2016. The rate of revascularisation by PCI increased from 16.0% to 31.0%, a greater increase than revascularisation by CABG, which increased from 4.6% to 6.5%. Increases in procedures were observed in all age groups and both sexes. The proportions of coronary angiograms that resulted in revascularisation each year consistently ranged from 67 to 70% throughout the period.

Acute coronary syndrome hospitalisation rates in New Zealand decreased by nearly 40% between 2006 and 2016, while the use of coronary angiography and revascularisation after ACS nearly doubled. The similar proportions of angiograms that resulted in revascularisation each year suggests that, despite the doubling of angiograms over the 10-year study period, they are not over-utilised.