Following transplantation, heart transplant patients undergo 5-20 invasive, expensive, and imprecise surgical biopsies to monitor for acute rejection. Exoscope is developing a revolutionary non-invasive diagnostic to relieve patients and clinicians of this burden and enable precision immunosuppressive care. Our technology interrogates enriched exosome populations secreted by immune and donor heart cells to provide a molecular window into rejection pathophysiology. If integrated into care, this would reduce mortality, improve quality of life, and lower burden of care for heart transplant recipients.