Executive Leadership
Meet our Dignity Health Mercy Gilbert Medical Center team
President & Chief Executive Officer
Mark F. Slyter is the President and CEO of Dignity Health’s Arizona East Valley market which includes Mercy Gilbert Medical Center and Chandler Regional Medical Center.
During Mark’s 25-year career, he has achieved progressive healthcare experience as the chief executive officer or hospital president in small, medium, and large hospitals then advancing to serve as the CEO in tertiary and academic health systems. He produces substantial improvements across a balanced scorecard of safety, quality, finance, value, growth and patient, employee and physician satisfaction. Mark rallies key stakeholders to embrace new approaches and achieve a culture of high reliability in patient-centered care.
Prior to joining Dignity Health, Mark was President and CEO of General Health System / Baton Rouge General, a three-hospital system with 686 beds, two regional-referral and academic-medical-center campuses, a rehabilitation facility, and clinics. During his tenure, Baton Rouge General Mid-City Hospital transformed into a post-acute specialty campus, improved operating margins, reduced costs, and achieved high patient-satisfaction and employee-engagement scores.
Mark was also president and chief executive officer at Mississippi Baptist Health Systems, in Jackson, Miss., where he enhanced operating margins and efficiencies while dramatically increasing patient satisfaction. He has led both start-up academic medical centers and established major teaching hospitals that annually trained more than 500 medical students, residents, fellows, nurses, technologists, and other healthcare professionals.
President & Chief Executive Officer
Mark F. Slyter is the President and CEO of Dignity Health’s Arizona East Valley market which includes Mercy Gilbert Medical Center and Chandler Regional Medical Center.
During Mark’s 25-year career, he has achieved progressive healthcare experience as the chief executive officer or hospital president in small, medium, and large hospitals then advancing to serve as the CEO in tertiary and academic health systems. He produces substantial improvements across a balanced scorecard of safety, quality, finance, value, growth and patient, employee and physician satisfaction. Mark rallies key stakeholders to embrace new approaches and achieve a culture of high reliability in patient-centered care.
Prior to joining Dignity Health, Mark was President and CEO of General Health System / Baton Rouge General, a three-hospital system with 686 beds, two regional-referral and academic-medical-center campuses, a rehabilitation facility, and clinics. During his tenure, Baton Rouge General Mid-City Hospital transformed into a post-acute specialty campus, improved operating margins, reduced costs, and achieved high patient-satisfaction and employee-engagement scores.
Mark was also president and chief executive officer at Mississippi Baptist Health Systems, in Jackson, Miss., where he enhanced operating margins and efficiencies while dramatically increasing patient satisfaction. He has led both start-up academic medical centers and established major teaching hospitals that annually trained more than 500 medical students, residents, fellows, nurses, technologists, and other healthcare professionals.
Chief Medical Officer
Erik Mattison, MD, FACEP is the Chief Medical Officer for Mercy Gilbert Medical Center (MGMC). In 2024, Dr. Mattison joined the executive leadership team.
Since 2004, Dr. Mattison has practiced as an Emergency Medicine physician at Chandler Regional Medical Center (CRMC) and Mercy Gilbert Medical Center. He has served as the Medical Director at CRMC Emergency Department, Department Chairman of the Emergency Department at both CRMC and MGMC and as the President-elect of the Medical Staff for CRMC and MGMC. Dr. Mattison has served on numerous hospital quality and safety committees including serving as chair of the Medical Staff Quality Committee. He is board certified in both Emergency and Addiction Medicine.
Dr. Erik Mattison completed his undergraduate biology degree at the University of Michigan with High Honors. He attended Case Western Reserve Medical School in Cleveland, Ohio. Dr. Mattison then moved to the Southwest for his Emergency Medicine training at Maricopa Medical Center in Phoenix, Arizona. Dr. Mattison served as Chief Resident and received the Outstanding Resident Award (voted by attending physicians) and Residents Award (voted by fellow residents).
Chief Medical Officer
Erik Mattison, MD, FACEP is the Chief Medical Officer for Mercy Gilbert Medical Center (MGMC). In 2024, Dr. Mattison joined the executive leadership team.
Since 2004, Dr. Mattison has practiced as an Emergency Medicine physician at Chandler Regional Medical Center (CRMC) and Mercy Gilbert Medical Center. He has served as the Medical Director at CRMC Emergency Department, Department Chairman of the Emergency Department at both CRMC and MGMC and as the President-elect of the Medical Staff for CRMC and MGMC. Dr. Mattison has served on numerous hospital quality and safety committees including serving as chair of the Medical Staff Quality Committee. He is board certified in both Emergency and Addiction Medicine.
Dr. Erik Mattison completed his undergraduate biology degree at the University of Michigan with High Honors. He attended Case Western Reserve Medical School in Cleveland, Ohio. Dr. Mattison then moved to the Southwest for his Emergency Medicine training at Maricopa Medical Center in Phoenix, Arizona. Dr. Mattison served as Chief Resident and received the Outstanding Resident Award (voted by attending physicians) and Residents Award (voted by fellow residents).
Vice President, Operations
Rudy Apodaca is the Vice President of Operations for Mercy Gilbert Medical Center. He has been a healthcare administrator for more than 36 years - 15 in leadership and management roles.
Rudy provides executive oversight for a number of departments including laboratory, pharmacy, environmental services, nutrition services, diagnostic imaging, and rehabilitation. He is also the orthopedic and spine service line executive strategic leader for the East Valley and oversees the development and growth of the East Valley Primary Stroke Center and Chest Pain Certification.
Rudy received his bachelor’s degree in radiologic technology at Wayland Baptist University in Texas and is a certified Radiology Administrator with radiation technology licensing in Texas, Florida and Arizona. He is a proud graduate of our Ministry Leadership Formation Program.
Additionally, Rudy serves and volunteers in the local community as a founding member and board member of Improving Chandler Area Neighborhood (ICAN), a not-for-profit after school program. He is an active member of the Gilbert Board Chamber Leadership Program and is a member of the board of directors for the Queen Creek Chamber of Commerce, Chandler Education Foundation, East Valley Hispanic Chamber of Commerce and Spectrum Property Management Board.
Vice President, Operations
Rudy Apodaca is the Vice President of Operations for Mercy Gilbert Medical Center. He has been a healthcare administrator for more than 36 years - 15 in leadership and management roles.
Rudy provides executive oversight for a number of departments including laboratory, pharmacy, environmental services, nutrition services, diagnostic imaging, and rehabilitation. He is also the orthopedic and spine service line executive strategic leader for the East Valley and oversees the development and growth of the East Valley Primary Stroke Center and Chest Pain Certification.
Rudy received his bachelor’s degree in radiologic technology at Wayland Baptist University in Texas and is a certified Radiology Administrator with radiation technology licensing in Texas, Florida and Arizona. He is a proud graduate of our Ministry Leadership Formation Program.
Additionally, Rudy serves and volunteers in the local community as a founding member and board member of Improving Chandler Area Neighborhood (ICAN), a not-for-profit after school program. He is an active member of the Gilbert Board Chamber Leadership Program and is a member of the board of directors for the Queen Creek Chamber of Commerce, Chandler Education Foundation, East Valley Hispanic Chamber of Commerce and Spectrum Property Management Board.
Chief Operating Office (COO)
Jeff McBee is the Chief Operating Officer (COO) for Dignity Health Chandler East Valley, which includes Chandler Regional Medical Center and Mercy Gilbert Medical Center. As COO, he oversees daily operations for both East Valley hospitals and cardiovascular services forand both facilities.
Prior to his position with Dignity Health, Jeff served as Administrator of Rust Medical Center at Presbyterian Healthcare Services in New Mexico. He previously served in various leadership roles in hospital operations and supply chain at Maricopa Integrated Healthcare System, Phoenix; Parkland Hospital, Dallas, Tex., Duke University Health System, Durham, NC, and Guthrie Healthcare System in Sayre, Pa.
Jeff received his bachelor’s in psychology, master’s of health administration, and master’s of business administration from the University of Missouri-Columbia.
Jeff is a member of the American College of Healthcare Executives.
Chief Operating Office (COO)
Jeff McBee is the Chief Operating Officer (COO) for Dignity Health Chandler East Valley, which includes Chandler Regional Medical Center and Mercy Gilbert Medical Center. As COO, he oversees daily operations for both East Valley hospitals and cardiovascular services forand both facilities.
Prior to his position with Dignity Health, Jeff served as Administrator of Rust Medical Center at Presbyterian Healthcare Services in New Mexico. He previously served in various leadership roles in hospital operations and supply chain at Maricopa Integrated Healthcare System, Phoenix; Parkland Hospital, Dallas, Tex., Duke University Health System, Durham, NC, and Guthrie Healthcare System in Sayre, Pa.
Jeff received his bachelor’s in psychology, master’s of health administration, and master’s of business administration from the University of Missouri-Columbia.
Jeff is a member of the American College of Healthcare Executives.
Chief Financial Officer (CFO), Dignity Health East Valley
Eric Sorensen is the Chief Financial Officer for Dignity Health East Valley, which includes Chandler Regional Medical Center and Mercy Gilbert Medical Center. Eric is also the Interim CFO for Dignity Health in Arizona and Nevada, the Southwest Division of CommonSpirit Health.
Eric oversees the finance and decision support functions with a matrixed relationship with the corporate office for general accounting, payroll and accounts payable. He is also responsible for maintaining the relationship with Optum360 East Valley revenue cycle.
Eric received his Bachelor of Science in Health Care Administration and Master of Business Administration from the University of Arizona. He is also a Certified Public Accountant.
Chief Financial Officer (CFO), Dignity Health East Valley
Eric Sorensen is the Chief Financial Officer for Dignity Health East Valley, which includes Chandler Regional Medical Center and Mercy Gilbert Medical Center. Eric is also the Interim CFO for Dignity Health in Arizona and Nevada, the Southwest Division of CommonSpirit Health.
Eric oversees the finance and decision support functions with a matrixed relationship with the corporate office for general accounting, payroll and accounts payable. He is also responsible for maintaining the relationship with Optum360 East Valley revenue cycle.
Eric received his Bachelor of Science in Health Care Administration and Master of Business Administration from the University of Arizona. He is also a Certified Public Accountant.
Chief Nursing Executive
Meredith Hestand is the Chief Nursing Executive for Dignity Health Mercy Gilbert Medical Center, a position she’s held since 2020.
Her leadership ensures consistent and high-quality standards of patient-centered nursing care - managing all nursing resources; developing nursing policies and programs to comply with established standards, and implementing long-term strategic goals and objectives for the organization.
Meredith has been a Registered Nurse for 22 years, the last 17 with Dignity Health. She joined Chandler Regional Medical Center as a staff nurse in labor and delivery, was promoted to clinical supervisor and left the East Valley to manage St. Joseph’s Hospital and Medical Center’s labor care areas. She returned to Chandler Regional as Director of Maternal Child Health and then she assumed the role of Senior Director of Maternal Children Health for both Chandler Regional and Mercy Gilbert.
Meredith has master’s degrees in nursing and business administration, and is working on her doctorate of nursing practice. She also has a nurse executive board certification through American Nurses Credentialing Center and a graduate certificate in clinical ethics from the Alden March Bioethics Institute. She’s been twice nominated for the Arizona March of Dimes Nurse of the Year and was recognized with Dignity Health’s Acts of Humankindness Awards in 2016 and 2017.
Chief Nursing Executive
Meredith Hestand is the Chief Nursing Executive for Dignity Health Mercy Gilbert Medical Center, a position she’s held since 2020.
Her leadership ensures consistent and high-quality standards of patient-centered nursing care - managing all nursing resources; developing nursing policies and programs to comply with established standards, and implementing long-term strategic goals and objectives for the organization.
Meredith has been a Registered Nurse for 22 years, the last 17 with Dignity Health. She joined Chandler Regional Medical Center as a staff nurse in labor and delivery, was promoted to clinical supervisor and left the East Valley to manage St. Joseph’s Hospital and Medical Center’s labor care areas. She returned to Chandler Regional as Director of Maternal Child Health and then she assumed the role of Senior Director of Maternal Children Health for both Chandler Regional and Mercy Gilbert.
Meredith has master’s degrees in nursing and business administration, and is working on her doctorate of nursing practice. She also has a nurse executive board certification through American Nurses Credentialing Center and a graduate certificate in clinical ethics from the Alden March Bioethics Institute. She’s been twice nominated for the Arizona March of Dimes Nurse of the Year and was recognized with Dignity Health’s Acts of Humankindness Awards in 2016 and 2017.
Vice President, Mission Integration
Mario Valadez is the Market Vice President of Mission Integration for Dignity Health in Arizona’s eastern region which includes Arizona General Hospital-Mesa. Mario previously served as Senior Director of Mission Integration for Dignity Health’s East Valley hospitals. He has been with Dignity Health for 15 years. Mario’s inspiration comes from our founding legacy of the Sisters of Mercy and their rich heritage in faith.
He earned his master of divinity degree from Princeton Theological Seminary with an emphasis in pastoral counseling. His love for tradition and heritage was nourished in the seminary’s 200-year-old history. Early on, he began writing reflections and montages of his rich chaplain experiences, and found a deeper admiration for the things of God and how we connect with these “things”and each other.
Mario is the proud father of four children and husband to Sarah.
In his spare time, Mario enjoys square-foot gardening, cultivating his urban orchard and spending time with his wife and kids. He also enjoys traveling, hiking, restaurants and beaches.
Vice President, Mission Integration
Mario Valadez is the Market Vice President of Mission Integration for Dignity Health in Arizona’s eastern region which includes Arizona General Hospital-Mesa. Mario previously served as Senior Director of Mission Integration for Dignity Health’s East Valley hospitals. He has been with Dignity Health for 15 years. Mario’s inspiration comes from our founding legacy of the Sisters of Mercy and their rich heritage in faith.
He earned his master of divinity degree from Princeton Theological Seminary with an emphasis in pastoral counseling. His love for tradition and heritage was nourished in the seminary’s 200-year-old history. Early on, he began writing reflections and montages of his rich chaplain experiences, and found a deeper admiration for the things of God and how we connect with these “things”and each other.
Mario is the proud father of four children and husband to Sarah.
In his spare time, Mario enjoys square-foot gardening, cultivating his urban orchard and spending time with his wife and kids. He also enjoys traveling, hiking, restaurants and beaches.