Sudden cardiac arrest (SCA) is the most common cause of death in patients with coronary artery disease. In Europe, there are about 350 000 out of hospital SCAs per year. Mostly, ventricular tachycardia and ventricular fibrillation are the underlying aetiology of SCA, which is claimed to be successfully treated by a novel defibrillation therapy, a wearable cardioverter defibrillator (WCD).

This assessment, performed within the "European Network for Health Technology Assessment (EUnetHTA) Joint Action 3, aimed to provide valid data on clinical effectiveness and safety of the WCD. Furthermore, the project intended to elicit patients’ views on aspects regarding their cardiac disease and the WCD therapy as well as to identify neglected outcomes.

According to the published data, no statement can be made about the device's effectiveness – further research is needed. Studies suggest that the WCD could be a relatively safe intervention in the short to medium term. However, more data and more adequate reporting of (serious) adverse events are needed in order to establish the device safety. In particular, more data is needed for specific risk stratification of high risk patients in order to further narrow down the wide range of indications for WCD use.