Leadership

Jamie Yoo

Jamie Yoo

Chief Executive Officer

Jamie Yoo is the Chief Executive Officer (CEO) of CHA Hollywood Presbyterian Medical Center (CHA HPMC). An accomplished healthcare executive, Jamie has extensive leadership experience in development and execution of strategic plans for organizations with a wide range of products and service lines. Jamie joined CHA Health Systems, a global leader in the biotechnology industry which operates CHA HPMC, as Chief Strategic Operating Officer in June 2022.

Prior to joining CHA HPMC, he has served as a transformational leader in wide range of hospitals and healthcare organizations emphasizing cultural and measurable operational improvements. This includes executive roles serving as CEO of Anaheim Global Medical Center and South Coast Global Medical Center from 2020-2022 and as the COO at Silver Lake Medical Center from 2017-2019. Additionally, Jamie has led teams in a variety of functions, including operations, business development, strategy, and technology in local community-based hospital systems as well as in large academic medical centers.

As a leader, Jamie strives to facilitate effective communication within the organization and his team to achieve positive changes. His leadership principles have a foundation in being relentlessly positive, ensuring transparency, inclusive goal development, and focus on process improvement. He also recognizes the importance of relationships and has a proven ability to lead teams to create and maintain relationships with key customers, physicians, and community partners to increase access to care and community presence. Jamie displays a consistent history of measurable improvements to key operating metrics and maximizing productivity of the teams he works with.

Jamie earned his master’s degree in Business Administration from the Marshall School of Business at the University of Southern California. He is a native of Southern California and cares deeply about the local communities CHA HPMC serves.

Jamie Yoo

Chief Executive Officer

Rohit Varma, MD, MPH

Rohit Varma, MD, MPH

Chief Medical Officer

Rohit Varma, MD, MPH, is the chief medical officer of CHA Hollywood Presbyterian Medical Center, a nationally recognized acute care facility providing compassionate support for Hollywood and its surrounding communities since 1924. He is also the founding director of Southern California Eye Institute (SCEI) located within CHA Hollywood Presbyterian Medical Center.

An accomplished physician-scientist and board-certified ophthalmologist, Dr. Rohit Varma is recognized worldwide as a visionary leader in glaucoma and the epidemiology of eye diseases. He is an expert on changes in the optic nerve in glaucoma and is also studying new imaging techniques in the early diagnosis of glaucomatous optic nerve damage. 

Dr. Varma’s primary research focuses on epidemiologic studies of eye disease in children and aging populations. He is principal investigator of several National Institutes of Health-funded studies, including the African American Eye Disease Study, the Chinese American Eye Study, the Los Angeles Latino Eye Study and the Multi-Ethnic Pediatric Eye Diseases Study. His epidemiological studies have significantly impacted health care policy and have allowed for a deeper understanding of how disease affects different populations. Most recently, Varma has been involved in the development of novel implantable intraocular pressure sensors and drainage devices.

Dr. Rohit Varma also served as principal investigator for studies on blindness and vision impairment for the World Health Organization. Further, he is one of the highest National Institutes of Health-funded vision investigators, with continuous funding for more than two decades, demonstrating the importance, relevance and impact of his work.

Dr. Varma has authored or co-authored more than 275 articles in peer-reviewed journals and edited or authored three books. He serves on the Institute of Medicine’s Roundtable on Health Disparities and sat on the Board of the Scientific Counselors of the National Eye Institute.

He is a member of several prestigious academic societies, including the Association for Research in Vision and Ophthalmology, the American Glaucoma Society and the American Academy of Ophthalmology, which has awarded him its Secretariat Award and its Lifetime Achievement Award. He also received the Innovation in Medicine Award from the National Medical Fellowships Foundation and the President’s Award from the Glaucoma Research Foundation.

Prior to founding the SCEI, Dr. Rohit Varma was professor of ophthalmology and preventive medicine and the Grace and Emery Beardsley Chair in Ophthalmology at Keck School of Medicine of USC. Previously he served as dean of the Keck School of Medicine of USC, and president and chair of the Board of Directors of USC Care. He was also chair of the Department of Ophthalmology, and founding director of the USC Gayle and Edward Roski Eye Institute. In addition, he served as associate dean for strategic planning and community network development.

Dr. Varma was professor and chair of the Illinois Eye and Ear Infirmary at the University of Illinois at Chicago where he held the Charles I. Young Endowed Chair of Ocular Research and served as associate dean of strategic planning.

Dr. Varma completed his residency in ophthalmology at the internationally renowned Wilmer Eye Institute at Johns Hopkins School of Medicine, as well as earning a master of public health degree from Johns Hopkins School of Public Health, both located in Baltimore. He completed two glaucoma fellowships, one at the Wills Eye Hospital in Philadelphia and the other at Keck School of Medicine of USC. A native of India, he obtained his medical degree from the University of Delhi.

Rohit Varma, MD, MPH

Chief Medical Officer

Nate Mabry

Nate Mabry

Chief Operating Officer

Nate Mabry MSN, RN, CENP is the Chief Operating Officer at CHA Hollywood Presbyterian Medical Center (CHA HPMC). Nate has nearly 20 years of experience in the healthcare industry spanning a wide variety of clinical roles and direct leadership oversight of inpatient care units, emergency services, surgical and procedural services and women’s health. At CHA HPMC, he is responsible for the delivery of safe and effective nursing care.

Throughout his career, Nate has held many leadership roles. Most recently, he served as an executive with oversight of Perioperative Services, Women’s Health, and multiple clinical institutes at Providence Saint John’s Health Center.

Nate holds a Bachelor’s degree in Nursing and a Master’s degree in Nursing Leadership and Administration. He recently received his Certification for Executive Nursing Practice (CENP) from the American Organization of Nursing Leadership (AONL).

Nate Mabry

Chief Operating Officer

Usrah Hamzie

Usrah Hamzie

Chief Nursing Officer

Usrah Hamzie is the Chief Nursing Officer at CHA Hollywood Presbyterian Medical Center (CHA HPMC). In this role, Usrah provides the direction and oversight of nursing care, ensuring adherence to regulatory standards.

An accomplished nursing leader, Usrah has extensive experience and expertise in clinical operations and leadership roles. She began her career as a clinical supervisor in Emergency Department at CHA HPMC where she has spent over 20 years in various leadership positions. Throughout her career, Usrah has demonstrated outstanding leadership skills, a strong commitment to patient safety, and advancing clinical excellence.

Usrah Hamzie

Chief Nursing Officer

Dr. Borah Kim, MD, PhD, MBA

Dr. Borah Kim, MD, PhD, MBA

Chief Project Officer, Project Management Office

Dr. Borah Kim is a highly accomplished healthcare professional, currently serving as the Chief Project Officer in the Project Management Office at CHA Hollywood Presbyterian Medical Center. With extensive experience spanning providers, pharma, med-tech, and academia, she brings a diverse background to her role. Dr. Kim's primary focus is driving the successful execution of strategic projects, aligning with the CEO's vision to deliver exceptional value to patients, staff, and stakeholders. Previously, she held the position of Chief Growth Officer at CHA Health System, spearheading successful growth initiatives and exploring new business opportunities.

Dr. Kim is not only a seasoned healthcare executive but also a board-certified and fellowship-trained psychiatrist with a deep passion for mental health innovations. Combining her medical expertise and business acumen, she leads the development of novel therapeutics and digital health-tech products that positively impact people's lives. Additionally, Dr. Kim has provided valuable insights as a physician consultant for a pharma/biotech company on market strategy and a med-tech start-up on medical device development, broadening her understanding of the industry's challenges and opportunities.

With a remarkable 15-year academic medicine career, Dr. Kim has contributed significantly to the field. She has published over 50 high-ranking international papers and secured numerous government research grants. Her impressive track record showcases her commitment to advancing healthcare through research and innovation.

Dr. Borah Kim, MD, PhD, MBA

Chief Project Officer, Project Management Office

Jason Williams

Jason Williams

Chief Information Officer

Jason Williams is the Chief Information Officer at CHA Hollywood Presbyterian Medical Center (CHA HPMC). He is responsible for stabilization and optimization of our EHR system, along with strengthening IT infrastructure and enhancing patient record systems. He has over 20 years of experience in healthcare and has extensive knowledge of healthcare IT requirements and compliance.

Prior to joining CHA HPMC, Jason served in numerous roles, including regional IT manager at West Anaheim Medical Center, overseeing applications and Infrastructure for four hospitals. Most recently, he served as the IT manager at Olympia Medical Center where he managed the IT department and was responsible for IT procurement, budgeting, and streamlining processes.

Jason holds a Bachelor’s degree in Business Administration Accounting from California State University. He is a certified HIPAA professional and a HIPAA Security Specialist. Jason also holds various training certifications in Meditech (integrated EHR software), Client Server MIS and Client Server PCM, among other technical certifications.

Jason Williams

Vice President of Support Services and Chief Information Officer

Thomas W. Baumann

Thomas W. Baumann

Vice President of Strategic Planning and Business Development

Tom Baumann is the Vice President of Strategic Planning and Business Development and the Director of Imaging Services at CHA Hollywood Presbyterian Medical Center (CHA HPMC). As part of the executive team, he oversees strategic planning, development of new programs and services, and physician recruitment and retention.

Tom has over 30 years of experience in the healthcare industry spanning various management roles. Most recently, Tom served as the Vice President of Business Development at the Southern California Hospital in Culver City. Previously, he served as the Director of Diagnostic Imaging and Radiation Oncology at the Good Samaritan Hospital, Los Angeles, from 1988 to 1996. He was later promoted as the Director of Business and Physician Development and was instrumental in bringing new programs and services such as Gamma Knife radio surgery, lithotripsy, deep brain stimulation for Parkinson’s disease, Transfusion Free Medicine and Surgery, and expanding international medical referral services to Guam and Micronesia. Tom holds a lifetime teaching credential for the State of California Community Colleges and continues teaching as part of the Pasadena City College Radiology Technology Program since 1986. For 14 years, he developed and taught the ARRT “Advance Placement” year long course for experienced and practicing radiology technologists in preparation for the ARRT examination. He has been invited as a guest speaker on several occasions at CSRT State and Local conferences.

Tom has also donated his time to volunteer and charitable organizations. He has served on the Board of Directors of Culver City Downtown Business Association and as past-president of the Retirement Housing Foundation at Angelus Plaza, Los Angeles. He has received the Presidential Call for Service Award and was nominated for Hospital Association Southern California Employee of the Year Award. Tom helped establish at medical mission service AMNET International which provides ambulance and other critical health care equipment to the people of Guam and Micronesia. He has also served in the US Air Force from 1972-1976 as an EMT paramedic and Radiology Technologist.

Ask him to mix you your favorite cocktail, at times, he moonlights as a professional bartender.

Thomas W. Baumann

Vice President of Strategic Planning and Business Development

Linette Martin

Linette Martin

Vice President of Quality and Risk Management

Linette Martin is the Vice President of Quality and Risk Management at CHA HPMC and has dedicated her career in being an agent of change. With over 13 years of experience in the Quality and Risk Management field in healthcare, Linette has successfully developed and implemented ‘Just Culture’ and High Reliability Organization programs, established enterprise risk management systems, and has provided support for organization’s Leapfrog, the Centers for Medicare and Medicaid Services (CMS) ratings, and quality programs. At CHA HPMC, she oversees the development, management, implementation and sustainability of all quality assurance and improvement activities, compliance procedures, safety and risk management programs, as well as patient relations.

Linette is passionate about the healthcare industry and takes pride in knowing that the Quality Department plays a major role in steering CHA HPMC to provide safe and trusted care in alignment with our strategic goals. During her tenure at CHA HPMC, she has assisted in resolving issues identified by the CMS and California Department of Public Health (CDPH), has worked with the leadership team on The Joint Commission (TJC) readiness, implemented CANDOR, TeamStepps, and other patient safety initiatives.

Raised in Arizona, Linette completed her Masters in Industrial and Organizational Psychology at Alliant International University, Los Angeles

Linette Martin

Vice President of Quality and Risk Management