Meet Our Executive Team

John G. RaffoulJohn G. Raffoul, DPA, FACHE 
President & CEO

Mara BryantMara C. Bryant 
Chief Operating Officer

Vice President, Finance

BPatricia StonePatricia Stone, RN, MSN 
Senior Vice President of Nursing & Chief Nurse Executive

Mary Anne ChernMary Anne Chern, FAHP, ACFRE 
Senior Vice President, Fund Development & External Relations

Cesar Armendariz
Cesar Armendariz ​
Associate Vice President, Community & Public Relations / Marketing & Communications


Karen Hansberger, MD​
Sr. Vice President, Adventist Health
Senior Vice President & Chief Medical Officer

Greg SchwarzGreg Schwarz
Vice President, Business Development


Adventist Health Southern California Region (includes Adventist Health Glendale, Adventist Health Simi Valley and Adventist Health White Memorial)

Beth D. ZacharyBeth D. Zachary, FACHE 
President & CEO, Southern California Region

Ron WehtjeRon Wehtje
Chief Financial Officer, Southern California Region

Roland FargoRoland Fargo
Senior Vice President of Business Strategy & President of Medical Services Network, Southern California Region

Natasha Milatovich
Natasha Milatovich, MBA, MHRM 
Regional Vice President, Human Performance, Southern California Region

Arby Nahapetian, MDArby Nahapetian, MD
Chief Medical Officer, Southern California Region

Medical Staff Leadership

Adventist Health White Memorial is a unique community-based teaching hospital serving East and South Los Angeles. The non-profit, 353-bed hospital is committed to improving the health of the community by providing high quality and comprehensive care with inpatient and outpatient services. White Memorial was established in 1913, and today is regionally recognized for state-of-the-art technology and specialty care services provided by some of the best physicians in Los Angeles whose credentials include pioneering research, ivy-league education, and a commitment to compassionate and culturally-competent care. For more information, visit www.adventisthealth.org/white-memorial.

Adventist Health is a faith-based, nonprofit integrated health delivery system serving communities in California, Hawaii, Oregon and Washington. Our workforce of 31,000 includes more than 22,350 employees; 4,800 medical staff physicians; and 3,850 volunteers. Founded on Seventh-day Adventist heritage and values, Adventist Health provides compassionate care in 20 hospitals, more than 275 clinics (hospital-based, rural health and physician clinics), 15 home care agencies, seven hospice agencies and four joint-venture retirement centers. Visit AdventistHealth.org for more information.