Are emotions measurable? A narrative review on wearable technologies between neuroscience and cardiology

INTRODUCTION: Understanding how emotional processes arise from interactions between the brain and heart is crucial for advancing integrated approaches to cardiovascular and mental health. Wearable technologies offer new opportunities to objectively evaluate this heart - brain relationship in real time. AREAS COVERED: This narrative review examines studies evaluating emotional states using smart wearable devices used in cardiology. A literature search was conducted across PubMed, Web of Science, Cochrane Library, and Scopus, focusing on the past decade. From 2205 identified records, 9 studies were included. Both single-parameter (e.g. heart rate variability) and multi-parameter devices were analyzed to determine their effectiveness in detecting emotional states and supporting holistic cardiac health management. EXPERT OPINION: Wearable devices represent a promising tool for linking emotional and cardiovascular dynamics, with single-parameter systems currently offering more reliable signal interpretation. Further research is needed to refine multi-parameter integration and enhance personalized, emotion-informed cardiac care.