South Korean medical AI startup Yeji X has raised seed funding from Kakao Ventures and Schmidt. The company was founded by Sung Hyun Jung, former CEO of Promedius, which commercialized Korea’s first AI-powered osteoporosis diagnosis solution. Before leading Promedius, Jung headed global business development at Lunit, where he successfully expanded the medical AI company’s international footprint.

Yeji X focuses on heart failure, a condition with one of the highest hospital readmission rates among all diseases. More than 20% of discharged heart failure patients are readmitted within 30 days due to worsening symptoms. In the United States, Medicare applies a prospective payment system to heart failure cases, meaning readmissions directly impact hospitals’ financial performance. Furthermore, the Centers for Medicare & Medicaid Services (CMS) enforces the Hospital Readmissions Reduction Program (HRRP), which penalizes hospitals with high readmission rates—sometimes exceeding USD 5 million per year.

To address this issue, Yeji X has developed a multimodal foundation model that integrates electronic health record (EHR) data with medical imaging, enabling a 30-day readmission risk prediction algorithm for heart failure patients.

This technology allows hospitals to accurately identify high-risk patients prior to discharge, enabling targeted post-discharge management. By lowering readmission rates, hospitals can reduce multi-million-dollar penalties, secure additional bed capacity, and improve profitability through more efficient patient turnover.

Joo Yeon Jung, Senior Associate at Kakao Ventures who led the investment, commented, “Yeji X is a team that deeply understands both the structural challenges of healthcare systems and the value of medical AI. We decided to invest because of their clear vision to enhance efficiency and reduce readmissions through innovative multimodal AI technology.”

Sung Hyun Jung, CEO of Yeji X, stated, “Our goal is to go beyond diagnosis — to predict patient outcomes using AI, ultimately improving hospital operations and profitability. With this investment, we plan to further advance our technology and establish a foundation for entry into the U.S. market.”