Dr. Johnson is the Chair of the Division of Pediatric Cardiology at the Mayo Clinic in Rochester, MN, where he also directs the Pediatric Heart Transplantation program. Dr. Johnson's primary clinical focus is taking care of patients with complex congenital heart disease, as well as those with cardiomyopathy or heart failure, or those who have required heart transplantation or ventricular assist device (VAD) placement. Dr. Johnson is also interested in cardiac imaging, including fetal, transthoracic and transesophageal echocardiography, and studies how these imaging modalities can be used to improve patient outcomes in heart failure and transplant patients.