Recent advances in miniaturization of ultra-low power components allow for more intelligent wearable health monitors. The development and evaluation of a wireless wearable electrocardiogram (ECG) monitor to detect epileptic seizures from changes in the cardiac rhythm is described. The ECG data are analyzed by embedded algorithms: a robust beat-detection algorithm combined with a real-time epileptic seizure detector. In its current implementation, the proposed prototype is 52× 36× 15mm3, and has an autonomy of one day. Based on data collected on the first three epilepsy patients, preliminary clinical results are provided. Wireless, miniaturized and comfortable, this prototype opens new perspectives for health monitoring.