Delays in recognizing symptoms and seeking emergency medical service (EMS) worsen outcomes in acute coronary syndrome (ACS), yet changing patient help-seeking behavior remains challenging. A stepped-wedge cluster randomized clinical trial published in JAMA Network Open evaluated whether the Heart Matters community education program could improve EMS use across 8 high-risk communities in Victoria, Australia (4 metropolitan and 4 rural regions), representing approximately 792,000 adult residents.

The trial was conducted from December 2021 to March 2023, with follow-up through March 2024. Communities crossed to the intervention every 4 months. The multicomponent program included 490 community sessions reaching approximately 10,088 residents, more than 174,110 household mailouts, over 50,000 educational handouts, opportunistic media, and a geotargeted social media campaign reaching approximately 350,000 residents.

Among 1,775 patients with ACS identified from administrative datasets (865 intervention, 910 control; 52.1% aged ≥65 years; 67.2% male), EMS transport occurred in 68.6% during the control period and 63.4% during the intervention period (adjusted RD −8.98%; 95% CI −17.50% to −0.46%; P=0.04; adjusted OR 0.67; 95% CI 0.45-1.01; P=0.05). Reductions were greater in metropolitan regions (RD −10.73%) and during severe flooding events (RD −13.50%). Early treatment-seeking was also lower, although estimates were imprecise.

EMS use was unexpectedly high during the initial control period, coinciding with a COVID-19 wave. Program evaluation also identified concerns about EMS cost, service demand, and wait times. The intervention did not improve EMS use, underscoring how external events and structural barriers may blunt the effect of community education alone.