Artificial intelligence can draft preliminary interpretations of echocardiograms—heart ultrasound exams—with accuracy comparable to reports prepared by sonographers and cardiologists, according to new, independent, preliminary late-breaking science presented at the American Heart Association’s Scientific Sessions 2026 in Chicago. The randomized trial also found that AI assistance cut the time cardiologists spent interpreting each scan almost in half, from 8.5 minutes to 4.6 minutes, a time savings of about 46%.
An echocardiogram is the most widely used type of heart imaging, providing key information to diagnose heart conditions and select treatment options. Typically, a sonographer acquires the images and a cardiologist reviews them and writes a report. In this study, an AI tool, a sonographer and a cardiologist each prepared preliminary reports for the same 1,200 echocardiograms previously acquired during routine clinical care. The reports were randomly assigned to cardiologists for review and finalization without knowing who or what prepared the first draft.
Researchers assessed accuracy by how often cardiologists made substantial changes to the preliminary interpretations. Cardiologists made substantial changes to 50.6% of AI-generated reports, compared with 49.7% of human-prepared reports, meeting the study’s criteria for non-inferiority. The AI-assisted reports were also more consistent with historical reports in the medical record, and reviewing cardiologists could not identify whether the preliminary interpretation was prepared by AI or a human.
“We designed this study to capture even small differences between the preliminary reports and the cardiologists’ final interpretations, allowing us to take a careful look at how well AI performed in a rigorous scientific manner,” said co-senior author Keane K. Lee, M.D., M.S., a cardiologist at Kaiser Permanente Santa Clara Homestead Medical Center in Santa Clara, California. “Based on our prior work, we expected AI to demonstrate excellent accuracy, which was confirmed in this randomized trial. However, what surprised us was the extent to which using AI-generated reports reduced the time cardiologists needed to interpret echocardiograms.”
The findings matter because the demand for cardiology care is rising while the workforce is projected to shrink. According to a July 2026 study published in the Journal of the American Heart Association, experts anticipate a shortage of cardiologists in the U.S. over the next two decades, with projections estimating a national shortfall of about 7,000 cardiologists by 2036. “Because of the large number of echocardiograms cardiologists read, even a few minutes saved per interpretation can add up to a significant amount of time over the course of a day,” Lee said. “For patients, this could potentially mean faster turnaround of results and more access to care, and for cardiologists, more time to spend with patients.”
Lee emphasized that AI cannot replace the human team. “The cardiologist remains ultimately responsible for interpreting the echocardiogram and certifying the accuracy of the final report, even when AI assists with the process,” he said. The study did not test whether AI-assisted interpretation improves patients’ long-term health, and cardiologists knew they were part of the study, so they may have adjusted their usual work patterns. More research is needed in real-world clinical settings with larger volumes of exams.
The full abstract is available in the American Heart Association Scientific Sessions 2026 Online Program Planner. Additional resources, including multimedia, are available on the right column of the release link. The American Heart Association has also published a scientific statement on the Use of Artificial Intelligence in Improving Outcomes in Heart Disease A Scientific Statement From the American Heart Association. The study was presented at the American Heart Association’s Scientific Sessions 2026 and is considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.
