Pediatric Cardiology Fellowship

City Park Denver

The Pediatric Cardiology Fellowship Training Program began at the University of Colorado School of Medicine (CU SOM) Department of Pediatrics and Children's Hospital Colorado in 1971. Children's Colorado is a freestanding children's hospital with full affiliation with the University of Colorado School of Medicine for training pediatric residents and fellows. In addition to Children's Colorado, our fellows spend time at the University of Colorado Hospital and Denver Health Medical Center, the county hospital for Denver. The clinical service draws patients not only from the state of Colorado, but from Wyoming, Montana, North and South Dakota, Nebraska, Kansas, Utah, and New Mexico. We service a population base of approximately five million. The fellowship is fully accredited by the American Medical Association, the American Board of Pediatrics, and the Accreditation Council of Graduate Medical Education. The mission of our program is to prepare trainees for careers in academic pediatric cardiology. We accomplish this through a three-year program with substantial exposure to a broad spectrum of congenital and acquired heart defects and extensive time spent in active basic, clinical, translational research. Over 98% of the fellows who have completed the program are board certified and are practicing pediatric cardiology. The current philosophy of the fellowship program is to have three new fellows each year.

We also offer a fourth year of advanced training in:

Program Aims

  1. To prepare trainees to provide patient-centered, comprehensive cardiac inpatient and outpatient care for pediatric patients and families, with a focus on promoting patient safety and quality improvement and developing excellent communication skills.

  2. To provide outstanding opportunities in basic science, translational, clinical, educational research and quality improvement methodology that prepare fellows for successful careers in academic pediatrics.

  3. To provide outstanding opportunities in procedural learning in cardiac catheterization, echocardiography, electrophysiology, cardiac intensive care, and cardiothoracic surgery.

  4. To teach trainees strategies to maintain wellness (of self and others), to build resilience, and to minimize burnout.

  5. To provide trainees with opportunities to individualize elements of their educational program in a way that allows them to explore diverse career options and that aligns with their career goals.

  6. To build and maintain an infrastructure to recruit diverse fellows and provide an inclusive learning environment that promotes and celebrates differences.


Clinical goals of our training program are to provide comprehensive training in all areas of pediatric cardiology practice. Fellows rotate primarily at Children’s Hospital Colorado, but will also spend time at University of Colorado Hospital and Denver Health Medical Center. Under the supervision of a large and diverse faculty, trainees gain exposure to patients with a broad spectrum of clinical problems. Learning from direct patient care is augmented by a comprehensive series of lectures focused on congenital and acquired cardiology. Additional seminars provide training in communication, ethics, and practice administration. Fellows receive ample opportunities to learn the common procedures employed in cardiology.

Scope of Clinical Training

Fellows in our program develop the clinical skills necessary to prepare them to competently and confidently manage the broad spectrum of conditions that fall within the practice of pediatric and adult congenital cardiology. The combination of three clinical sites, each with distinct patient populations, enhances the opportunities to become familiar with a broad range of ages and clinical problems.

Clinical Schedule

1st-year 2nd-year 3rd-year
Cardiac Progressive Care Unit Consult/City Cardiac Progressive Care Unit
Consult Cardiac Intensive Care Unit Consult/City
Cardiac Intensive Care Unit Echocardiography Echocardiography
Cardiac Intensive Care Unit Cardiac Catheterization Cardiac Catheterization
Cardiac Catheterization Electrophysiology Elective
Cardiac Catheterization Heart Failure/Transplant Adult Congenital Heart Disease
Echocardiography Research Outpatient
Echocardiography Research Research
Echocardiography Research Research
Heart Failure/Transplant Research Research
Electrophysiology Research Research
Research Research Research
Vacation Research Research

All clinical activity during fellowship occurs at Children’s Colorado, University of Colorado Hospital, or Denver Health Medical Center. The clinical schedule is broken into discrete 4-week blocks and over the course of the fellowship, each trainee will spend 25 blocks on a clinical service. The clinical schedule is intentionally front loaded, with fellows spending 12 blocks on service during their first year of training. During each of the last 2 years, a fellow spends 13 blocks on service. There is some flexibility in the apportionment of clinical blocks, so that if an individual fellow would prefer more clinical time at one site over another, modifications to the basic structure may be possible.

All trainees are assigned to a continuity clinic, scheduled for one afternoon per week. Those fellows interested in a longitudinal follow-up experience with individual patients have the flexibility to schedule those patients on their assigned clinic afternoons. Additionally, trainees can participate in outreach community based cardiology clinics.

Patient Volume

Cardiology outpatient clinics are held daily at Children's Hospital Colorado, with half-day metropolitan Denver clinics held weekly in Broomfield, Littleton, Wheat Ridge, and Parker. In addition, there are approximately 62 out-of-town pediatric cardiology clinics per year, which the fellows will attend on a selected but consistent basis. There are approximately 21,000 outpatient clinic visits per year at Children's Hospital Colorado. This includes visits at our main campus in Aurora, our network of care locations in the Denver Metro area and Colorado Springs, as well as our outreach locations in Southern Colorado, Western Colorado and Wyoming

There are approximately 830 pediatric cardiac catheterizations performed per calendar year at Children's Hospital Colorado Heart Institute. The fellows can participate in all cardiac catheterizations.

The cardiac thoracic surgery service performs approximately 550 open and closed heart procedures each year at Children's Colorado. More than 20,000 outpatient and inpatient echocardiograms are performed at annually at Children's Hospital Colorado. In addition, Children's is a regional cardiac transplantation center for children, including newborns.

Call Responsibilities

As with all aspects of clinical training, the program encourages progressive responsibility and increasing autonomy when on-call. All calls during fellowship are in-house and include continuity care of all cardiac inpatients and cardiac consultations. The number of calls for first year a fellow is approximately 55, second year averages 45 calls, and third year fellows approximately 35. The fellows are expected to arrange the call schedule for themselves and to submit it for publication prior to July and December of every year.


Three weeks' vacation in blocks of one to two weeks is allowed per year per ACGME policy. Vacation time off must be approved by the Program Director.​​


Research training is a major focus of the fellowship training program and fellows are provided substantial protected time throughout their fellowship to engage in rich research experiences. The research program is designed to provide comprehensive scholarly training that prepares all trainees with the background and skills to successfully compete for academic faculty positions and extramural funding at the completion of their fellowship. Although many cardiology fellows are mentored by a faculty member within the Division of Pediatric Cardiology, the program encourages fellows to consider a broad range of potential mentors. The program will assist in identifying potential mentors, both within the Department of Pediatrics and, when appropriate, from across the School of Medicine campus.

Research facilities are available throughout Children’s Hospital Colorado and the University of Colorado School of Medicine. In the section of Cardiology, research facilities include a state-of-the-art echocardiography, cardiac catheterization, and electrophysiology laboratories, as well as a state-of-the-art flow lab. At the University of Colorado, multiple basic science laboratories are available including molecular biology laboratories, immunology laboratories, and perinatal research facilities among others.

Opportunities and Resources

Research opportunities available to cardiology trainees are broad and varied. The Exercise Physiology Laboratory, Echocardiographic Laboratory, Catheterization Laboratory, and Cardiac Intensive Care Unit within the Children's Hospital Colorado are all very well suited for clinical research. In addition, Children's Hospital Colorado Research Institute or Colorado Clinical Translational Sciences Institute (CCTSI) may provide "seed money" for new clinical and laboratory research.

Financial support and Human Research Committee assistance requires three to six months for preparation and approval. Approved and funded projects could begin early in the second year of fellowship. Participation in on-going projects may begin during the first year. Full-time research coordinators are available to assist in coordinating patient recruitment and data collection at the two sites.


During the first month of assigned research time, a trainee will typically meet with several potential mentors to discuss possible research projects and become familiar with different research programs. In the case of a basic science program, the fellow may “shadow” in individual labs in which they are interested. With the help of the Program Director, the goal is for the fellow to choose a mentor and research project in the first year. Once a research program is chosen, a timeline for research activity is developed by the mentor and the trainee. Broadly, the goal for research projects is for the fellow to have made sufficient progress that they can consider submission of an abstract to a national meeting by the middle of their second year. In general, research time during the third year of fellowship should be spent analyzing data, undertaking additional experimentation as necessary based in initial data analysis and feedback, preparing presentations and manuscripts, and planning follow-up projects.

Colorado Clinical Translational Sciences Institute (CCTSI)

The Colorado Clinical and Translational Sciences Institute is a collaborative enterprise between University of Colorado Denver, University of Colorado at Boulder, six affiliated hospitals and health care organizations, and multiple community organizations with resources to promote research and training that will advance health care and improve the public health. The CCTSI was established in 2008 with funding from the Clinical and Translational Science Award (CTSA) initiative of the National Institutes of Health (NIH). Through the CCTSI, Clinical Translational Research Centers (CTRCs) have been established at several affiliated hospitals, including The Children’s Hospital, University of Colorado Hospital, and Denver Health Medical Center. The CTRCs support research with clinical inpatient and outpatient space, inpatient research beds, nursing and research staff support, and core laboratory and nutrition services. To access CTRC resources, investigators submit a clinical protocol for review by the Scientific Advisory and Review Committee (SARC). The SARC review process gives investigators experience that may improve future COMIRB (Colorado Multiple Institutional Review Board) and grant applications. The CTRC also offers biostatistical collaboration/consultation for study design, including sample size and power calculations, data analysis, and manuscript preparation. To fulfill its mission to train future researchers, the CCTSI offers ongoing comprehensive educational programs in several areas, including Informatics, Biomedical Ethics, Biostatistics, and Study Design. Biostatisticians are also available for consultation on individual research projects through the Colorado Biostatistics Consortium (CBC). For more information, please see

Scholarship Oversight Committees

Each fellow is assigned a Scholarly Oversight Committee (SOC), composed of at least 3 faculty members. The SOC meets every six months to evaluate the fellow’s scholarly progress and to help provide support and direction. At the end of training, the SOC is responsible for determining whether the fellow’s work has met the American Board of Pediatrics requirement for sub-board eligibility.

Fellowship Conference

View the Children’s Hospital Colorado Conference Schedule for Pediatric Cardiology Fellows​
(Fellows should attend those conference that match their rotation schedule)

Fellows in pediatric cardiology meet several times weekly to discuss selected topics. In addition to the full-time faculty members in pediatric cardiology, outside speakers will be invited to these conferences. Each conference is prepared by a fellow or faculty member on a rotating or conference specific basis.

Surgical/Case Conference

A weekly pediatric cardiology/cardiothoracic problem case conference is held at Children's Hospital Colorado. Interesting pediatric cardiology cases will be presented and discussed. Scheduled surgery cases for the week are presented and surgical inpatients are reviewed. The cases are presented by the cardiology fellows with active input from both cardiac surgery and pediatric cardiology faculty. Presentation of cases as well as pertinent electrocardiograms, chest x-rays, echocardiograms, and catheterization data is the responsibility of the fellow.

Journal Club

Weekly Book and Journal Club is held. Journal articles or book chapters will be assigned prior to the meeting and the pertinent science and analysis will be discussed. This is an excellent opportunity for the fellows to meet with the staff on an informal basis to discuss timely issues.

Board Review

A quarterly board review session is held. This session utilizes an audience response system to collect answers to board style questions.

Department of Pediatrics Education

This educational series was recently developed to address areas of scholarly interest common to all pediatric core fellowships. Fellows attend 5-6 half-day seminars spread across their 3 years of fellowship. Attendance is mandatory and the trainee is excused from clinical responsibilities. In addition to providing core educational material, these sessions allow trainees in different disciplines throughout the department to meet and interact with one another in an informal and collegial environment.

Topics for this curriculum: Pediatric Fellowship Educational Series


Formal introductory instruction in biostatistics is give during the second year of fellowship through a 6-session, 12-hour biostatistics course that is taught by a PhD biostatistician. In addition, fellows have access (in-person or online) to regular biostatistics seminars which are provided by the CCTSI. Trainees who undertake advanced graduate coursework with a biostatistics component (Masters in Public Health or Masters in Clinical Science) may be exempt from the introductory course.

Additional Opportunities

Although not required for completion of the fellowship, some trainees pursue additional graduate coursework during their fellowship. The University of Colorado School of Public Health, which is on the Anschutz Medical Campus, offers a Masters of Public Health. The University of Colorado Denver Graduate School offers a graduate program in clinical science, which awards a Masters of Science in Clinical Science (MSCS). This program provides training in clinical sciences through theoretical and methodological coursework and its application to an individual research project. Funding for additional graduate coursework is not guaranteed, but may be available on an individual basis.

National Meetings

Cardiology fellows are encouraged to attend regional and national scientific meetings throughout their fellowship. Among the meetings commonly attended by cardiology fellows are the annual American Heart Association, American College of Cardiology, American Society of Echocardiography, International Society for Heart and Lung Transplantation, Pediatric Cardiac Intensive Care Society, and the Western Society of Pediatric Cardiology (WSOPC) meetings. To support academic development, including travel to meetings, the section supports attendance to national meetings for 2nd, 3rd and 4th year fellows. Fellows are encouraged to submit at least one abstract per year. In addition, the section supports travel to any national meeting for which the trainee has an abstract accepted.

 1st Year Fellows


Nadia Chaudhry-Waterman, DO
Medical School: Edward Via College of Osteopathic Medicine-Virginia Campus
Residency: Inova Children's Hospital's Pediatric Residency 
Email: Nadia.Chaudhry-Waterman



Kelsey Guerins Iguidbashian, MD
Medical School: Creighton University School of Medicine
Residency: University of Colorado Pediatric Residency 
Email: Kelsey.Iguidbashian


Benjamin A. Olsen, MD
Medical School: Creighton University School of Medicine
Residency: University of Colorado Pediatric Residency 
Email: Benjamin.Olsen



Lauren M. Zager, MD
Medical School: University of Wisconsin School of Medicine
Residency: University of Utah Pediatric Residency 
Email: Lauren.Zager

2nd Year Fellows


Samantha Ann Kops, MD
Medical School:  University of Arizona College of Medicine 
Residency:  University of Arizona College of Medicine
Email:  Samantha.Kops



    Jeffrey Michael Shuler, MD
    Medical School:  University of Missouri School of Medicine
    Residency:  Cincinnati Children's Hospital



      Charles Thomas Simpkin, DO
      Medical School: Rocky Vista University of Osteopathic Medicine
      Residency:   University of Colorado Pediatric Residency
      Email:  Charles.Simpkin


      3rd Year Fellows


      Michael "Adam" Carlisle

      • Medical School: University of Alabama SOM
      • Residency: Children's Hospital Colorado 
      • Research Interest: Development of Standardized Crisis Resource Management Toolkits for Pediatric ICU Care



      Shannon Murray, MD

      • Medical School:  University of Wisconsin School of Medicine and Public Health
      • Residency:  Medical College of Wisconsin and Affiliated Hospitals
      • Research Interest: TBD



      Kevin Pettit, MD

      • Medical School:  University of Iowa Roy J. and Lucille A. Carver College of Medicine
      • Residency: University of Wisconsin, Madison
      • Research Interest:  TBD



      Kathryn Reynolds, MD

      • Medical School:  The Brody School of Medicine at East Carolina University
      • Residency:  Johns Hopkins All Children's Hospital
      • Research Interest: TBD


       Advanced Pediatric Cardiology Fellows

      Kevin Kilgallon, MD - Intensive Care


      Barry O'Callaghan, MD - Interventional Cardiology



      Michael Shorofsky, MD - Interventional Cardiology


      Hieu Ta, MD - Cardiac Imaging



      Diana Tsen, MD - Cardiac Imaging


      Dana Irrer, MD - Adult Congenital


      The Application Process

      Our pediatric fellowships will be conducting virtual interviews for this upcoming interview season.  We look forward to sharing our programs with you and getting to know more about you.  Our planned virtual interview dates are forthcoming.


      If you have questions about the application process feel free to reach out to our program coordinator.


      We particularly hope to attract applicants who are motivated and self-directed learners who want to develop academic careers based on excellence in research, scholarship, and clinical pediatric and adult congenital cardiology. To be considered for admission to our program, applicants must have successfully completed training in a 3-year ACGME-accredited residency program in Pediatrics. The Pediatric Cardiology Fellowship utilizes ERAS - Electronic Residency Application Service (ERAS). We participate in the National Residency Matching Program (NRMP) and do not offer any positions outside of the match. The application should include a copy of your curriculum vitae, at least 3 letters of reference, a personal statement highlighting why you wish to become a pediatric cardiologist, and your USMLE or COMLEX score reports. If you are not a US citizen, include a copy of your ECFMG report with ERAS. Please bear in mind that you would need to acquire a J1 visa if selected as a candidate for our program. Incomplete or late applications will not be considered. It is your responsibility to ensure all required information has been received.


      ERAS Application Timeline

      Monday, May 31, 2022ERAS 2021 season ends at 5 p.m. ET.
      Wednesday, June 8, 2022ERAS 2022 season begins at 9 a.m. ET.
      Thursday, June 9, 2022EFDO will release tokens to fellowship applicants.
      Wednesday, July 6, 2022July cycle fellowship applicants may begin submitting applications to programs at 9 a.m. ET.
      Wednesday, July 20, 2022July cycle fellowship programs may begin reviewing applications at 9 a.m. ET.
      May 31, 2023    ERAS 2022 season ends at 5 p.m. ET.


      NRMP Fall Match Timeline

      Wednesday, August 24, 2022Match Opens 
      Wednesday, September 28, 2022Ranking Opens
      Wednesday, November 1, 2022Quota Change Deadline
      Wednesday, November 2, 2022Rank Order List Certification Deadline
      Wednesday, November 30, 2022MATCH DAY

      Salary and Benefits

      The University of Colorado offers salary and benefits packages that are competitive with other fellowship programs across the country. Current salary levels can be found at the School of Medicine - Graduate Medical Education Stipends.


      The Mile High City is nestled at the eastern base of the Rocky Mountains and is the largest city in the region with a population of over 2.7 million. Denver enjoys one of the best climates in the country, with 300 days/year of sunny skies. Although it snows in the winter, the snow melts quickly and temperatures are usually moderate. Hot summer days give way to cool summer evenings. The city is the home to dozens of highly rated restaurants and a vibrant nightlife. The city attracts many outdoor enthusiasts with its extensive system of hiking and bike trails and the largest city park system in the country. The Denver Center for the Performing Arts is the largest performing arts complex under one roof in the country and attracts many of the top national theater tours each year. Red Rocks Amphitheater, a natural amphitheater in the foothills west of town, attracts the nation’s top touring musical talent throughout the summer.

      Denver is home to the Denver Broncos (NFL), the Denver Nuggets (NBA), the Colorado Rockies (MLB), the Colorado Avalanche (NHL), the Colorado Rapids (MLS) and the Colorado Outlaws (MLL). The University of Colorado, the state flagship school and a world-class educational institution, is based in nearby Boulder. In addition, Denver is the gateway to the Rocky Mountains, which offer abundant recreational and sightseeing opportunities year round. The state of Colorado is home to over 20 major ski areas, many of which are within 2 hours of the city.

      Additional Questions

      Please contact Jeanette Starkey, Fellowship Coordinator for any questions you may have. 720-777-2940 or

      Welcome to Children’s Hospital Colorado for your pediatric cardiology fellowship interview!


      We are so excited to meet you and help you get to know our program. We wanted to take this opportunity to outline our objectives for the remainder of your day. We hope our program is presented in an enjoyable and user-friendly way. We will focus on some nuts and bolts, but more importantly, want you to take away facets of our training program that are unique to Colorado. We are very proud of our fellows as well as the quality of our training program and we hope it shows. Although we believe our mission is to train well-rounded general pediatric cardiologists, we want to prepare you for the next steps of your career. To that end, we have tailored some of your interview day experiences to your personal interests. We hope your interview day allows you and us to have a great sense about whether we are a good fit for each other.


      Why I chose Children’s Hospital of Colorado for Pediatric Cardiology Fellowship

      A Fellow’s Perspective


      1. People
      • Faculty are approachable and are excellent teachers.
      • We are all on a first name basis.
      • Co-fellows are awesome!


        1. Atmosphere
          • Have a question for the surgeons? Just ask them.
          • The attendings just text back and forth with us if questions come up about patients.


        2. Size
          • Perfect learning opportunity to fellow ratio
          • Expanding with interesting and diverse case mix
          • Extremely large catchment area


        3. Fellow role
          • We work hard and are integral to the Heart Institute, but are not required for the services to function. In other words, we are not a “fellow dependent” program.


        4. Opportunities for scholarship and collaboration
          • Mentors are easy to find.
          • Resources exist that make it easier to do aspects of data collection and analysis (database managers, informatics, statistical support).
          • Collaborations abound throughout the University of Colorado for multidisciplinary projects.
          • Children’s Hospital Colorado is a leader in Pediatric Quality Improvement.


        5. Flexible program leadership that listens and responds to fellows’ concerns
          • When things are not working, the leadership tries to fix it as soon as possible.


        6. Work/life balance
          • We have a night float system. The weeks on nights are hard, but it is better than Q4 call and you always have the weekend off those weeks.
          • Denver is a fantastic place to live.
          • There is no better way to decompress than getting away for a hiking or skiing trip.
      Well-Being / Resilience

      Be well

      By embracing wellness and improving personal resiliency, physicians can reconnect with the meaning of their work and fend off stress. Reducing or eliminating burnout also has practical implications for the entire department such as improving patient safety, student advancement, and the overall campus environment. 

      Visit our Pediatric Well-Being and Resilience website...

      Diversity / Equity / Inclusion


      We are committed to creating a diverse environment for students, residents, fellows, and faculty. We believe that an environment of inclusiveness and respect promotes excellence and that a setting where diversity is valued leads to the training of physicians who are prepared to practice culturally effective medicine and meet the needs of the various populations we serve. Visit our Diversity, Equity, and Inclusion in PEM page for more.