Todd Caliva

Chief Executive Officer

Todd Caliva serves as Chief Executive Officer (CEO) of HCA Houston Healthcare Clear Lake and is regarded in the industry as a consummate healthcare professional. He has more than 26 years of experience, including a decade at the multi-facility level. He has been with HCA Houston Healthcare since 1997.

In prior roles, Caliva served as CEO of HCA Houston Healthcare West and Chief Operating Officer of The Woman's Hospital of Texas. His strategic vision, leadership, compassion and relationship-building skills allowed those facilities to flourish in its staff recruitment, patient and visitor experience and market presence.

Caliva believes commitment to quality healthcare begins with employees. If employees enjoy what they do and are committed to our values, then our patients will get the quality care and service they deserve.

Caliva is co-chair of the SouthEast Texas Regional Advisory Council Cardiac Care Committee, an organization that is committed to improving the overall care for heart attack patients across the region. He also serves on the board of directors for Bay Area Houston Economic Partnership.

Caliva earned a master's degree in business administration from the University of Houston.

William Killinger

Chief Medical Officer

William Killinger, MD, is the Chief Medical Officer (CMO) at HCA Houston Healthcare Clear Lake.

Prior to joining HCA Houston Clear Lake, Dr. Killinger was the CMO at Medical Center of Trinity, an HCA West Florida Division hospital. He was in private practice for 27 years in Raleigh, North Carolina, as a cardiothoracic surgeon and served as a guest editor for The Annals of Thoracic Surgery and The Heart Surgery Forum®.

He also served as the vice chairman and chairman of the department of surgery at WakeMed Health and Hospitals in Raleigh. Dr. Killinger was medical director of the cardiothoracic surgery intensive care unit, and in 2016 was appointed medical director of the cardiovascular and thoracic surgery programs at WakeMed Health and Hospitals.

Dr. Killinger graduated from Emory University in Atlanta, Georgia, and the University of Virginia School of Medicine and received his master's degree in business administration from Brandeis University in Boston, Massachusetts. After completing general surgery at The University of North Carolina at Chapel Hill, he trained in cardiothoracic surgery at the University of Pittsburgh and then served as a clinical associate staff member at the Cleveland Clinic for three years.

Elias Armendariz, FACHE

Chief Operating Officer

Elias Armendariz, FACHE, is the Chief Operating Officer (COO) and Ethics and Compliance Officer at HCA Houston Healthcare Clear Lake.

Before joining HCA Houston Clear Lake, Armendariz was a member of the senior leadership teams at Methodist Hospital Northeast and Methodist Children’s Hospital in San Antonio, which are part of the HCA San Antonio Division. He also previously served as Chief Nursing Officer, COO and Vice President of Operations at El Paso Children’s Hospital, and Director of cardiovascular and critical care services at University Medical Center of El Paso.

Armendariz received his bachelor’s degree in nursing from The University of Texas Health Science Center at San Antonio and a master’s degree in nursing systems management from The University of Texas at El Paso.

Natalie Pack

Chief Financial Officer

Natalie Pack serves as the Chief Financial Officer (CFO) of HCA Houston Healthcare Clear Lake and HCA Houston Healthcare Mainland.

From 2019-2021, Pack served as the vice president of finance for the HCA Gulf Coast Division from. During her tenure as the Division VP, she supported HCA Houston Healthcare Medical Center as its interim CFO and chief staffing officer. She is an HCA veteran and has held leadership roles at St. David’s North Austin Medical Center in Austin, Texas, Medical City Plano in Plano, Texas, and Sunrise Hospital and Medical Center in Las Vegas, NV.

Pack holds a bachelor’s degree in accounting from Christian Brothers University in Memphis, TN, a master’s degree in accounting from the University of Memphis in Memphis, TN, and a master’s degree in healthcare administration from the University of Florida in Gainesville, FL.

Sherry Camacho

Chief Nursing Officer

Sherry Camacho is the Chief Nursing Officer (CNO) at HCA Houston Healthcare Clear Lake. Camacho was previously CNO at Valley Regional Medical Center, an HCA hospital in Brownsville. She has been an HCA employee for more than 20 years and is passionate about healthcare and nursing.

Camacho earned her bachelor’s degree in nursing and a master’s degree in healthcare administration from Western Governors University.

She has been married to her high school sweetheart for more than 25 years and is a strong believer in giving back to the community through volunteer work.