Dr. Gillen received his undergraduate degree from the University of Pennsylvania in Philadelphia, PA, and his medical degree from Jefferson Medical College at Thomas Jefferson University in Philadelphia, PA. Subsequently, he completed his residency in internal medicine and fellowship in cardiovascular diseases at the Lankenau Hospital in Wynnewood, PA.
Dr. Gillen is Board Certified in both internal medicine and cardiovascular diseases. He has been practicing cardiology since 1994. Dr. Gillen's current practice includes non-invasive and invasive cardiology.