Cardiac organoids in toxicology: from construction strategies and research trends to precision screening applications

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, with significant attention focused on the development of therapeutic drugs and research into pathogenic mechanisms. In the real world, cardiotoxicity induced by multiple factors commonly exists and is closely associated with cardiovascular diseases. Traditional toxicity testing models (such as animal experiments and two-dimensional cell cultures) have limited clinical translation value due to species differences, inability to simulate the complex microenvironment of the human body, and cellular interactions. Cardiac organoids, as an emerging three-dimensional (3D) culture platform, possess 3D structure, multicellular composition, organ-specific functions, and self-organizing capabilities, which can highly mimic the physiological and pathological characteristics of the heart, providing a more precise humanized model for the study of cardiovascular disease mechanisms, drug development, and toxicity assessment. This paper systematically reviews the construction strategies of cardiac organoids and their application progress in toxicology: Firstly, it explores the construction standards and technical optimization of cardiac organoids, focusing on human-engineered heart tissue (hEHT) models and various cardiac organoid models that mimic the human heart, with particular attention to their unique characteristics, utility, and limitations. Secondly, through bibliometric analysis using CiteSpace, it reveals research hotspots and trends in cardiac organoid applications for toxicology, specifically by extracting collaboration networks, conducting co-citation analysis, and co-occurrence analysis. Finally, it summarizes specific applications of cardiac organoids in toxicology, including drug toxicity assessment, environmental pollutant toxicity evaluation, cardiac developmental toxicity studies, disease model construction, and multi-organ cascade studies for systemic toxicity assessment.