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Executive Leadership

Meet our Dignity Health Arizona team.


Tim Bricker, MHSA

President, CommonSpirit Health Central Region

Tim Bricker

Tim Bricker is the CommonSpirit Central Region President, which covers Dignity Health points of care in Arizona and Nevada and CHI points of care in Iowa, Minnesota, Nebraska, and North Dakota. Prior to being named Central Region president, Tim was the CommonSpirit Southwest Division president and CEO.

Tim previously served as Senior Vice President and Chief Executive of MultiCare Health System - South Sound Region in Tacoma, Wash., and as a health care consultant for McKinsey and Company. Tim was president of Dignity Health Chandler Regional and Mercy Gilbert Medical Centers from January 2011 to April 2017.

Tim has nearly 30 years of health care leadership experience, working for systems throughout the western United States, including Intermountain Healthcare, St. Charles Health System, and ECG Management Consultants. He has a Master’s of Health Services Administration from University of Michigan and a Bachelor of Arts in public and international affairs from Princeton University.

Brian Tiffany, MD, PhD

Chief Medical Officer, CommonSpirit Health Central Region

Brian TiffanyDr. Brian Tiffany is the Chief Medical Officer for CommonSpirit’s Central Region. He advances clinical excellence, performance, and alignment by building strong physician relationships and engagement, enhancing care delivery and contributing to growth initiatives.

Dr. Tiffany has been a valuable member of the Dignity Health team for many years. He most recently served as Chief Medical Officer of CommonSpirit Health’s Southwest Division. Prior to that role, he was the Chief Medical Officer for Dignity Health Arizona General Hospital, overseeing clinical operations for both Laveen and Mesa campuses and their hospital satellite emergency departments.

He is a member of the Dignity Health Chandler Regional and Mercy Gilbert Medical Centers medical staffs and is the chairman of the East Valley Regional Institutional Review Board.

Dr. Tiffany has practiced emergency medicine since 1990. He received his doctor of medicine from Washington University School of Medicine and his doctor of philosophy from Wayne State University.


Kathleen Rondeau

Chief Strategy Officer, CommonSpirit Health Central Region

Kathleen Rondeau

Kathleen “Kat” Rondeau is Chief Strategy Officer for CommonSpirit's Central Region. She is responsible for strategic planning and management to enhance division the region’s growth and access to care throughout the states.

Kat leads efforts to create and sustain an integrated delivery system across the continuum of care while evaluating and facilitating growth opportunities including mergers, acquisitions and joint venture opportunities. She ensures positive stakeholder relations and develops and plans service lines. Kat also oversees strategy and business development

Kat  has a Master of Business Administration from Capella University and a Bachelor of Science in dietetics from the University of Wisconsin where she completed her dietetic internship at the Cleveland Clinic Foundation in Cleveland, Ohio. She is also a Fellow with the American College of Healthcare Executives.

Bradley Pristelski

Chief Information Officer, CommonSpirit Health Central Region

Bradley Pristelski

Bradley Pristelski is Chief Information Officer for CommonSpirit's Central Region. Prior to joining CommonSpirit, Pristelski dedicated 12 years in the United States Air Force as a contingency combat operations officer throughout Europe, Asia, the Middle East, and Africa serving in Operations Enduring Freedom and Iraqi Freedom.

Bradley is dedicated to advancing digital and information technology prowess to ensure market competitiveness and advanced capability as well as shape and grow divisional technical talent. His passion focuses on a foundation of leadership designed around a collection of themed critical behaviors that increase or enhance a leader’s impact across everyday situations and contexts, influence team success and organizational development, produce loyal followership and achieve exceptional results.

Bradley also has the privilege to serve on the Arizona General Hospital Board of Directors and is an adjunct professor at Arizona State University focused on leadership, mindfulness, and community excellence in partnership with ASU’s Chief of Wellbeing.

Shirley Gunther

Vice President of External Affairs, CommonSpirit Health Central Region

Shirley Gunther

Shirley Gunther serves as the Vice President of External Affairs for CommonSpirit's Central Region.

She has more than 20 years of experience in public policy development, intergovernmental affairs, advocacy, and community relations both in the public and private sectors.

She advocates in support of CommonSpirit Health's mission and strategic plan. As a trusted senior adviser within the organization, she assists in advising and navigating the constantly changing legal and regulatory requirements.

Shirley is a graduate of Arizona State University where she earned her Bachelor of Arts degree, Master of Public Administration, and holds a Certification in Public Management.