He specializes in diagnostic radiology with an emphasis on cardiac imaging.Dr. Zimmerman earned his medical degree from the University of Pennsylvania School of Medicine. He completed both a radiology residency and a cardiovascular imaging fellowship at the Hospital of the University of Pennsylvania.His research focuses on cardiovascular imaging.Certified in diagnostic radiology by the American Board of Radiology, Dr. Zimmerman also serves on the faculty of the Johns Hopkins School of Medicine Office of Continuing Medical Education.