Rob Marmerstein

Chief executive officer

Robert Marmerstein

Robert Marmerstein joined HCA Houston Healthcare Tomball as the Chief Executive Officer (CEO) in July 2020. He will oversee the management and operations of the hospital ensuring both service line and overall strategic goals align with the development of the organization’s vision and strategic plan.

Marmerstein joined HCA Healthcare in 2009. Previously, he served as Chief Operating Officer (COO) of HCA Houston Kingwood for three years and as COO at HCA Houston Mainland for two years. He also served as an administrative resident at Reston Hospital Center in Reston, Virginia and as associate COO at LewisGale Medical Center in Salem, Va.

Marmerstein earned his bachelor of science degree in hospitality management from the University of Central Florida and a master's degree in Health Administration from Virginia Commonwealth University. He is a member of the American College of Healthcare Executives, a board member for the Kingwood Place West Commercial Association, and recently served as a board member of the Greater East Montgomery County Chamber of Commerce.


Robert Sabina

Chief operating officer

Robert Sabina

Robert Sabina joined HCA Houston Healthcare Tomball as the Chief Operating Officer (COO) in July of 2019. In his role, he is responsible for ensuring consistent department and service line strategy alignment as well as hospital facility initiatives including construction, new equipment, quality improvements, efficient utilization and the overall care environment of the facility.

Sabina served as an Assistant Vice President of Strategy (AVP) as part of HCA Healthcare Gulf Coast Division strategy and development group for two years. Before transitioning to HCA Healthcare, Sabina held progressive leadership roles across operations and strategy functions for other Houston-area healthcare systems since 2010. He has more than 13 years of healthcare experience and joined HCA Healthcare in 2017.

Sabina earned a bachelor of science from Purdue University and a dual master's in healthcare and business administration from the University of Minnesota. He currently serves as treasurer of the University of Minnesota Master of Healthcare Administration (MHA) Alumni Association.


Richard Ervin

Chief financial officer

Richard Ervin

Richard Ervin joined HCA Houston Healthcare Tomball as the Chief Financial Officer (CFO) in 2017. With over 24 years of accounting and finance experience, Ervin oversees management of all financial departments, allocation of resources and preparation of the annual budget including accounting and health information. Before joining HCA Healthcare, Ervin began his career with American Medical International in 1986, which later became Tenet Healthcare, where he served as CFO for 10 years then served as CFO for nine years with Community Health Systems in Tomball, Texas.

Ervin earned a bachelor’s of accounting from Stephen F. Austin State University. He currently serves on the board of directors of TOMGWA Health Care Ministries and is a member of Healthcare Financial Management Association.


Maggie Yacoubian, MSN, RN

Chief nursing officer

Maggie Yacoubian

Maggie Yacoubian joined HCA Houston Healthcare Tomball as the Chief Nursing Officer (CNO) in January 2019. As the CNO, Maggie is responsible for driving, supporting and modeling a culture focused on clinical excellence, employee engagement, quality, patient safety and the overall patient experience.

Yacoubian joined HCA Healthcare in 2012. With over 23 years of nursing experience, she served as the director and administrative director of clinical care and emergency services for Tristar Centennial Medical Center in Nashville, Tennessee for seven years.

Yacoubian earned a bachelor's of science in nursing from South University and a master's of science in nursing leadership and management from Western Governors University. She is a graduate of the HCA Executive Development Program and has been recognized as a Top Ten-High Performer for exceeding top hospital initiatives within HCA Healthcare's emergency room operations.