Scholars, mentors and partners in good health

Kennestone GME faculty and staff share a passion for the practice of community medicine. Committed educators skilled in adult learning theory pursue specialties in areas like public health, healthcare administration, epidemiology and healthcare disparities.

“I’ve always loved teaching and it is a humbling honor to be involved in the development of graduate education at WellStar, especially since I was born in Kennestone Hospital.”

~ G. Waldon Garriss III
John A. Brennan
Executive Vice President & Chief Clinical Integration Officer
Dr. Brennan is executive vice president and chief clinical integration officer. He will oversee clinical integration for WellStar, which includes: safety and quality, service lines, population health, Mayo Clinic Care Network, Center for Health Transformation (CHT), Graduate Medical Education and other related functions. Dr. Brennan joins WellStar from Barnabas Health in New Jersey, where he served as executive vice president and president & CEO of Newark Beth Israel Medical Center and Children’s Hospital of New Jersey. He has held numerous roles at Barnabas Health. In addition, Dr. Brennan has 20 years of experience practicing emergency medicine in the military, community health systems and two academic medical centers. He received an MPH from Columbia University, M.D. from Georgetown University School of Medicine and a B.S. in biology from LeMoyne College. He completed his residency at the University of Southern California LAC and is a board certified emergency medicine physician.
Joanne Zhu
Program Director, Transitional Year
Dr. Joanne Zhu received her master’s degree from the University of South Florida in Tampa, Fla. She received her medical degree from the University of Texas Southwestern Medical School in Dallas, Texas. Dr. Zhu completed her internal medicine residency at the University of North Carolina Hospitals in Chapel Hill, N.C. Dr. Zhu is board certified in internal medicine with focused practice in hospital medicine. She is a member of the American College of Physicians, American Association of Physician Leadership and the Society of Hospital Medicine. Dr. Zhu currently is in practice with WellStar Hospitalist Group – Kennestone.
Brandi Allen
Executive Director, GME
Brandi Allen is a fellowship trained healthcare administrator, with a passion for community health and health education. Her healthcare experience includes hospital operations, medical education, long term care, primary care and school based healthcare. Brandi joined WellStar in 2016.
Eduardo Estrella
Associate Program Director, OB/GYN
Dr. Estrella earned his bachelor’s degree from Sacred Heart University in San Juan, Puerto Rico. He completed his medical degree at the University of Puerto Rico School of Medicine in San Juan and his residency in obstetrics and gynecology at San Juan City Hospital. Dr. Estrella is board certified in obstetrics and gynecology. He is a member of the American Medical Association, a member of the American Academy of Gynecological Laparoscopists, a diplomate of the American Board of Obstetrics and Gynecology and a fellow of the American College of Obstetrics and Gynecology. Dr. Estrella is currently in practice with WellStar North Cobb Women’s Health.