Sonification enables continuous surveillance of the ST segment in the electrocardiogram.

INTRODUCTION

ST segment elevation myocardial infarction is a common reason for out-of-hospital cardiac arrest in adult patients. The surveillance of the ST segment in the electrocardiogram is limited to visual presentation. However, the ST segment can change during the course of treatment. If ST elevation is present immediate coronary revascularization is needed, therefore detecting ST elevation changes the treatment fundamentally. Sonification of the ST segment is a new method which enables the emergency team to detect intermediate changes of the ST segment.

MATERIAL AND METHODS

We have chosen two sonification designs which were introduced to two groups, medical students and computer science students. Twenty-one participants took part in the study. The sonification was designed for evaluation of the ST segment. The user was supposed to become empowered to distinguish between no, medium-low, medium-high or extreme ST elevation by listening to the sonification. The two groups were asked to evaluate the sounds for possible ST elevation as well as for aesthetics and usability. In a second study twenty-five medical students were taking part in a medical scenario in which sonification was played during a simulated case. The patient was suffering from a myocardial infarction, ST elevation was transient and sonification sounds were changing appropriately. The students were supposed to detect these changes and act accordingly by modifying the treatment.

RESULTS

Both groups were able to classify ST segment elevation by listening to the sonification samples. The higher the ST segment, the better was the detection rate overall. In all of the three categories (pleasantness, informativeness and long-term listening) the Water Ambience sonification was rated higher compared to the Polarity sonification. Moreover, in the two groups that took part in the study, we found a significant difference when comparing classification performance using both sonification designs. For the group of medical students as t(20) = 4.31, p = 3.44 × 10, p < 0.01 and for the computer science students as t(19) = 3.40, p = 9.39 × 10, p < 0.01. In the simulated medical scenario participants indicated that 96% detected the ST elevation. 60% stated that sonification played a role whereas for 32% it did not play a role for the detection of ST elevation.

CONCLUSIONS

Sonification has the potential to play an important role as a new supporting tool for the surveillance of the ST segment during the care of patients with suspicion of myocardial infarction. It can be helpful to differentiate between ST segment elevation myocardial infarction and non-ST segment myocardial infarction especially if ST elevation is transient. Furthermore, sonification is viewed as pleasant to listen to and might not contribute to alarm fatigue.