In 2021, Ehrin became the Medical Director at the Adventist Heart and Vascular Institute at Adventist Health, St. Helena Hospital in St. Helena, California. In the preceding seven years, he was the Professor of Medicine in the Division of Cardiology at the University of Colorado School of Medicine. He is also the Director of Interventional Cardiology. Ehrin combines the roles of medical practitioner, scholar and researcher. He divides his time between treating vascular disorders and emergency heart attack patients who may require surgical intervention, conducting advanced research into the causes of heart attacks at the molecular level and teaching medical residents and cardiology trainees. Ehrin has contributed chapters to many medical texts and his research has been published in the leading journals in the cardiology field. Ehrin is a 2002 Mitchell Scholar. He received an MSc. in Biotechnology from the University of Ulster. Interested in the network advantages of gathering together practitioners and innovators, Ehrin's research examined the opportunities for, and barriers to, establishing a technology cluster in Northern Ireland. His research gave him insight into how clustering of expertise could apply to healthcare and the development of long term health care policy. In the future Ehrin hopes his research on understanding the role of inflammatory cells in triggering myocardial infarction (heart attack) may lead to new diagnostic tests to identify people at high risk as well. Ehrin obtained his undergraduate degree from Stanford.