Implementation of a Night Service of Helicopter Transportation to Reduce the Time to Revascularization in STEMI Patients in a Mountainous Region: Impact on Outcomes

Background: Treatment delays are the most easily audited index of quality of care in the setting of ST-segment elevation myocardial infarction; among the components of ischemia time, system delay has been demonstrated to be a predictor of outcomes, and in a mountainous region it relies mostly upon helicopter rescue service. Aim: The aim of the study is to analyze the impact of the activation of helicopter rescue service for the nighttime for urgent transportation of patients on the time to revascularization and on the outcomes of STEMI patients. Methods: Data were prospectively collected in a database and retrospectively split into two different cohorts, based on the presentation date in the 18 months before, or after, the first day of implementation of the new organizational model. The patients were also split into two groups based on the place of STEMI diagnosis, either the chief town territory or the rest of the region, and retrospectively evaluated for vital status at 30 days and 2 years after index event. Results: The number of patients included was 751. For patients coming from outside Trento, an improvement in ST-segment resolution was shown (ST-segment elevation reduction >50% in 54.0% of the patients vs. 36.4%, p < 0.01). Moreover, a reduction in diagnosis-to-reperfusion median time has been demonstrated (from 105 to 97 min, p < 0.01), mainly driven by a reduction during the night shift (from 119 to 100 min, p = 0.02). With regard to 30-day and 2-year mortality, no statistically significant differences were achieved. Discussion: The organizational effort has translated into a significant reduction in the treatment delay for patients coming from outside the chief town. However, although a longer diagnosis to reperfusion time has been related to a higher mortality, a significant reduction in mortality was not demonstrated in our study. However, an improvement in ST-segment elevation resolution was shown for patients coming from outside the city of Trento, a result that could have other potential clinical benefits. Conclusions: Implementation of night flight proved to be effective in reducing the time between the diagnosis and the treatment of patients in the setting of STEMI, improving ST-segment elevation resolution, although no impact was shown on short- and long-term mortality.