Today there is solid evidence that high-risk patients with acute myocardial infarction without ST-elevation should undergo routine invasive treatment, preferably with a very short delay. Evidence suggests that acute coronary occlusions are present in many of these patients. Nevertheless, so far no studies have been powered to evaluate the impact of primary percutaneous coronary intervention on outcome in this patient population. With the advanced, prehospital, diagnostic possibilities available today it would be possible to investigate this issue further.