ST-Elevation Myocardial Infarction (STEMI) is a severe type of heart attack and a major cause of morbidity and mortality. However, outcomes can be optimised if key treatment modalities are performed early. Paramedics can play a strategic role in achieving this objective, as they are often the first healthcare professionals to encounter the STEMI patient. This project will trial two new approaches of autonomous clinical decision-making by paramedics, with an aim of improving treatment delivery times compared to current systems requiring physician oversight. We hypothesise that adopting such approaches will lead to improved patient outcomes, with reduced hospital admission times. Economic benefits are also likely. This study has the potential to benefit STEMI patients and their families, high risk groups such as Maori, and the wider community through reduction of mortality and morbidity and an increase in quality adjusted life years.