Meet our program faculty

Email: [email protected]
Specialty: Emergency Medicine
Medical School: University of Health Sciences/The Chicago Medical School
Residency: Wayne State University/Detroit Receiving Hospital
Awards and Honors: Voluntary Faculty Teacher of the Year 1998, 1999

Dr. Evan Leibner is a New York native, who graduated with a degree in Chemical Engineering from the University of Buffalo and received his Doctor of Medicine at The Chicago Medical School. He completed his Emergency Medicine training at Wayne State University/Detroit Receiving Hospital in 1995, and stayed on as faculty and Assistant Program Director. He moved to the Valley of the Sun in 1999, to serve as the Associate PD at the Maricopa County Medical Center EM Program. He has been practicing at Dignity Health East Valley CRMC and MGMC since 2003. He served as the Emergency Medicine group Director from 2011 to 2022. At DHEV, he has served as a member and as the Chair of the Multidisciplinary Quality Review Committee, as well as the Chair of the Department of Emergency Medicine. Dr. Leibner will be the Academic Chair of the Department of Emergency Medicine for the DHEV Residency Program. Outside the hospital, he enjoys hiking, running, traveling and SCUBA (not all at the same time). He has no interest in college sports. He likes spending time with his family and his two mutts.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Case Western Reserve University
Residency: Maricopa Medical Center, Phoenix
Awards and Honors: Chief Resident, Richard A. Walsh Outstanding Resident Award, Outstanding Resident Award

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 attendings) and Residents Award (voted by fellow residents). Since 2004, Dr. Mattison has practiced at Chandler Regional Medical Center (CRMC). He currently serves as both the Medical Director at CRMC Emergency Department and as the President-elect of the Medical Staff for Chandler Regional and Mercy Gilbert Medical Centers. Dr. Mattison has served on numerous hospital quality and safety committees. He is boarded in Emergency and Addiction Medicine. Outside of work, Dr. Mattison devotes his time to his wife and two children, stays active with swimming and running, crosswords and has an unhealthy obsession/passion for his beloved Iowa Hawkeyes.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: George Washington School of Medicine and Health Sciences, Washington, DC
Residency: University of Arizona-Tucson
Fellowship: University of California-Irvine, Multimedia Design Education Technology
Other Degrees: Masters in Health Professions' Education (MEHP), Johns Hopkins School of Education
Awards and Honors: Chief Resident (2016-2017), Emergency Medicine Residents' Association (EMRA) Presidential Leadership Award

Dr. Dimeo grew up in the Midwest, attending the University of Minnesota where she graduated summa cum laude as a Spanish major with a focus on pre-medical studies. Prior to matriculating into medical school, she served in a full time capacity as an Epic(R) electronic health records trainer and consultant (which proved to be a valuable skill in future years!). She ventured to Washington, D.C. for medical school at The George Washington University School of Medicine then completed her Emergency Medicine residency at the University of Arizona-Tucson, her final year serving as chief resident. Having found great joy in teaching students and residents, she devoted 2 years as a Multimedia Design Educational Technology fellow at the University of California-Irvine during which she completed her Masters in Health Professions' Education through Johns Hopkins. She also served on the EMRA board as the Director of Education during this time, a formative experience in her early career. She transitioned to become core faculty and launch a Medical Education and Technology Fellowship at Prisma Health in Greenville, South Carolina before settling into her new role at Dignity Health as their inaugural program director in 2023. Her professional interests lie in the use of games in education, slide design and educational technology, learner assessment, and feedback. She lives in Chandler with her two kids, two dogs, and husband and enjoys traveling whenever she is able, and all the outdoor activities that Arizona has to offer.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Michigan State University School of Osteopathic Medicine
Residency: Ascension Macomb-Oakland Macomb, Michigan
Awards and Honors: Chief Resident (2019-2020)

Dr. Ryan Adkins, is a Kentucky native originally from the foothills of the Appalachian mountains. He served as an infantry medic in the National Guard for six years which included a deployment to Baghdad, Iraq, where he gained lifelong friends and valuable life lessons.  Ryan spent about a decade in Michigan where he studied at Michigan State University College of Osteopathic Medicine and completed residency at Ascension Macomb-Oakland Hospital.  He has been involved in the Premier Emergency Medical Specialists Management Committee, and is the scheduler for the nocturnists. Based in Chandler, he finds joy in raising two young energetic children and practicing medicine in an appreciative and diverse patient population.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Indiana University School of Medicine
Residency: Indiana University Department of Emergency Medicine

Dr. Andrea Wolff completed her undergraduate and medical degrees at Indiana University, and completed residency training in 2007 at the Indiana University School of Medicine in Indianapolis before relocating to the Southwest, where she has practiced Emergency Medicine for over 15 years. Dr. Wolff has maintained board certification from the American Board of Emergency Medicine, and is a fellow of the American Academy of Emergency Medicine and the American College of Emergency Physicians. Her areas of interest include point-of-care ultrasound, palliative care, and the implementation of research into evidence-based practice. Dr. Wolff has been active in medical education since 2011 as the director of physician education for Emergency Medicine at Dignity Health East Valley, and has been a member of the clinical faculty at A.T. Still School of Medicine since 2015, providing a clerkship in Emergency Medicine for 3rd and 4th year medical students.  She has presented at a number of Emergency Medicine conferences locally and nationally, and maintains an online presence with free open-access medical education content.  Dr. Wolff has been working to develop the upcoming Emergency Medicine residency in the Dignity Health East Valley system and will be involved in Research, Education and Ultrasound training for the residency program.  Outside of medicine, Dr. Wolff believes in maintaining an active lifestyle; she is an avid runner and participates in competitive ballroom dancing.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Drexel University School of Medicine
Residency: University of Arizona-Tucson

Dr. Nicolas Enriquez is an Arizona native, having lived in Arizona since the age of two. He grew up in Tucson, Arizona and completed his undergraduate degree in Molecular and Cellular Biology at The University of Arizona (BEARDOWN!). After medical school in Philadelphia, Dr. Enriquez returned to the desert for his Emergency Medicine residency at The University of Arizona- Tucson. Dr. Enriquez has been a community Emergency Medicine Physician since graduation, working in Tucson and surrounding communities before joining Chandler Regional Medical Center and Mercy Gilbert Medical Center in late 2021. He will serve as the Diversity, Equity, and Inclusion Director. Dr. Enriquez enjoys world travel, music, good food and spending quality time with friends and family. 

Email: [email protected]
Specialty: Pediatrics, Pediatric Emergency Medicine
Medical School: Keck School of Medicine of USC
Residency: UT Southwestern/Children's Health
Fellowship: Children's Hospital of Philadelphia, Pediatric Emergency Medicine
Other Degrees: Masters in Healthcare Quality and Safety (MHQS), University of Pennsylvania
Awards and Honors: Chief Resident - Pediatrics (2019-2020)

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Kirksville College of Osteopathic Medicine, Kirksville, MO
Residency: Lehigh Valley Health Network, Allentown, PA
Awards and Honors: Chief Resident (2016-2017), Resident of the Year 2017, Physician of the Month Mercy Gilbert Medical Center (March 2023)

Dr. Tanner Folster completed his undergraduate education at the University of Utah, went on to medical school at Kirksville College of Osteopathic Medicine and then finished with residency at Lehigh Valley Health Network in Allentown, PA. Dr. Folster has a passion for teaching. It began as a teaching chief resident, and continues as faculty for Midwestern University - Glendale, which he has been doing since 2019. He has developed the new MSIII and MSIV clerkship for EVEM, and is the Clerkship Director. He is also the Physician Relations Director for the Emergency Medicine group at DHEV and leads hiring for Emergency Medicine physicians at Chandler Regional Medical Center/Mercy Gilbert Medical Center. He serves as the hospital medical director for the Code Blue Committee. Dr Folster is an avid swimmer and was a 5-time state champion and second team all Mountain West Conference when he swam division 1 for the University of Utah for 4 years. He enjoys spending time with his wife and his three very active children.

Email: [email protected]
Specialty: Emergency medicine
Medical School: Touro University Nevada College of Osteopathic Medicine
Residency: University of Arizona - Tucson
Awards and Honors: Critical Care Distinction Track 2017

Dr. Melissa Kelsey is an Arizona native who was born and raised in South Tempe, just a few miles from Chandler Regional Medical Center. She is a graduate of Barrett, the Honors College, at Arizona State University (Go Devils!) with a B.S. in biology and a minor in Spanish. Dr. Kelsey attended medical school at Touro University College of Osteopathic Medicine in Nevada where she also spent considerable time mentoring and tutoring other students. She completed Emergency Medicine residency training at University of Arizona - Tucson, graduating in 2017, subsequently joining the group at Dignity health East Valley. Dr. Kelsey is excited to be a part of the Dignity EVEM team and will be serving as Core Faculty for Wellbeing. She is passionate about teaching and firmly feels that it is possible to foster a culture of wellness within graduate medical education without compromising academic pursuits. Dr. Kelsey is also a member of the Dignity Physician Peer Support team. Her professional interests include critical care medicine, wellness and resiliency, ED ECMO, toxicology, and airway management. In her spare time, Dr. Kelsey enjoys hiking, kayaking, reading in the pool, scuba diving, weightlifting, cooking, watching sports, and spending time with family.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: University of Arizona College of Medicine - Tucson
Residency: University of Arizona - Tucson

Dr. Aubrey Bethel grew up in Arizona but spent her college years at Indiana Wesleyan University. After realizing she missed Arizona, she returned for medical school at University of Arizona College of Medicine in Tucson and stayed for residency, graduating in 2019.  She ended up in South Carolina following residency, where she practiced for several years in community medicine. After returning to Tucson in 2022, she went back for a fellowship in Simulation Medicine with University of Arizona. Dr. Bethel enjoys teaching all levels of students and loves the diversity in educational techniques that simulation offers. She especially enjoys making education fun and memorable. In her free time, she travels, hikes and finds creative outlets. She has dabbled in triathlons, marathons and obstacle races, and would like to do more. She is married to an adrenaline junkie F-16 pilot and they have a beautiful baby girl together.

Specialty: Emergency Medicine
Medical School: University of Nevada, Reno - School of Medicine
Residency: John Peter Smith Health Network, Fort Worth TX
Fellowship: John Peter Smith Health Network, Ultrasound
Other Degrees: Masters in Public Health (MPH) – Focus on Health Administration and Policy, University of Nevada Reno
Awards and Honors: Clinician of the Quarter (2021 & 2022), Professionalism in Medicine Award for Duty

Dr. Pavelka has an eclectic background, having worked in several different fields including but not limited to construction, public education, and military service prior to becoming a physician. Originally from Colorado, he has lived in several states, though most of his time and education occurred in Nevada. Dr. Pavelka started his medical career as an EMT in 2006 and worked in several settings prior to going to medical school at the University of Nevada. Having completed his emergency medicine and ultrasound training in Fort Worth, he now plans to apply this to an equally diverse array of interests. An outdoor enthusiast, Dr. Pavelka is also currently working towards his requirements as a Fellow of the Academy of Wilderness Medicine (FAWM) with the goal of doing excursion medicine in the future. He has traveled from Afghanistan to Uganda and would like to see all seven continents. Dr. Pavelka maintains his appreciation for EMS work, particularly in the setting of law enforcement. He has completed training through Counter Narcotics & Terrorism Operational Medical Support (CONTOM) and is looking to start working with local law enforcement as well. Dr. Pavelka lives with his wife and two dogs in Mesa, where she puts up with his equally diverse hobbies such as painting (albeit badly), axe throwing, and officiating weddings. 

Email: [email protected]
Specialty: Emergency Medicine, Pediatrics
Medical School: Des Moines University College of Osteopathic Medicine
Residency: Detroit Medical Center Wayne State University

Dr. Joshua Zeidler, DO, grew up in Los Angeles and attended undergrad at UC San Diego. He then moved to the Midwest and attended medical school at Des Moines University College of Osteopathic Medicine. He completed a combined residency in Emergency Medicine and General Pediatrics at Detroit Receiving Hospital and Children's Hospital of Michigan through Wayne State University in Detroit. He is also sub-specialty boarded in Emergency Medicine Services through the American Board of Emergency Medicine. He has been working at Chandler Regional and Mercy Gilbert Medical Centers for more than 20 years. He serves as the Medical Director for Dignity Health East Valley and Arizona General Hospitals, and is the Department Chair for Mercy Gilbert Medical Center. In addition, he works at a primary care and occupational health office for care of First Responders and their families. He is active in the training and oversight of pre-hospital medical providers and is the Medical Director for various East Valley Fire and EMS agencies. Dr. Zeidler is very excited about the educational opportunities that are offered at Dignity Health East Valley and is looking forward to working closely with the residents and medical students.

Email: [email protected]
Specialty: Emergency Medicine
Medical School: Edward Via College of Osteopathic Medicine – Carolinas Campus
Residency: Sparrow Hospital/Michigan State University
Awards and Honors: Chief Resident (2021-2022), Senior Teaching Award (2022)

Dr. Aryan Toosi is an Arizona native and obtained his bachelor’s degree at Arizona State University. He moved to Spartanburg, SC for medical school training and met his wife there. They participated in the couple’s match and both were accepted to complete their residencies at Sparrow Hospital/Michigan State University. You won’t find him climbing mountains or running half marathons during his time off as his preference would be to lounge about. Much to his wife’s dismay, he has a collection of Jordans that outnumber her entire shoe lot. He enjoys caring for his plants, beating souls-like games, and spending time with his wife and son. He has a passion for medical education and loves teaching those who are eager to learn!