Lisa Mikkelsen joined the company in March 2020 as the Chief Executive Officer. She is a seasoned healthcare executive with 17 years of multi-unit operations experience. Prior to joining WellStreet, Lisa was the COO of Benevis Dental Practice Management Services, the leading Medicaid-focused children’s dental support organization. Lisa thrives in taking a solutions-based approach to leading teams through growth and change. She is passionate about developing team members, building culture, and implementing systems and processes to effectively support growth.
The WellStreet Story
Founded in 2011 as an independent Urgent Care operator in Atlanta, Georgia, WellStreet quickly grew into a network of 7 locations within one year of operations. In 2014, our partnership model emerged as we partnered with Piedmont Healthcare to grow and expand the Piedmont Urgent Care brand across North Georgia. Our story continued in 2019, as we launched a partnership with Corewell Health, to deploy and operate a network of urgent cares under the Corewell Health Urgent Care brand in Southeastern Michigan.
WellStreet’s market footprint has continued evolving as additional partnerships launched in early 2023 with University Hospitals and Prisma Health. Despite our rapid growth, our teammates and leaders remain steadfast in our commitment to providing each and every patient with best-in-class quality and experience as we continue evolving to meet the patient needs of tomorrow!
Uncompromising Care…One Patient at a Time
Wellstreet Leadership
LISA MIKKELSEN
Chief Executive Officer
MICHAEL DUCHYNSKI, M.D.
Chief Medical Officer
Michael Duchynski, MD is a board certified Emergency Medicine physician who has spent the last decade in the urgent care space with WellStreet in various roles. He has been serving in the role of CMO of WellStreet since November 2021. Dr. Duke, as he is known, is passionate about delivering access to high quality, evidence based, and consistent care with a best in class patient experience across all WellStreet centers.
JIMMY KARVELAS
Chief Financial Officer
Jimmy Karvelas is an accomplished executive leader and financial strategist currently serving as the Chief Financial Officer at WellStreet Urgent Care in Atlanta, GA. With a wealth of experience spanning over two decades, Jimmy has consistently driven growth, profitability, and operational efficiency in the healthcare industry. His tenure at WellStreet, initially as Senior Vice President from 2019 to 2024, and now as CFO, has been marked by a focus on de novo growth and successful mergers and acquisitions.
Sara Mylenek
Chief Partnership Officer
Sara serves as WellStreet’s Chief Partnership Officer, leading the integration, growth, and long‑term success of the organization’s health system partnerships. She works closely with Health System executives and cross‑functional teams to ensure seamless launches and sustained operational excellence.
With 20 years of multi‑site retail healthcare experience, including seven years in Urgent Care, Sara has held a wide range of operational leadership roles spanning operations, continuous improvement, revenue cycle, and enterprise system implementations. Her expertise in scaling operations and optimizing performance has made her a trusted partner across clinical and administrative domains.
From 2023 to 2025, Sara contributed her industry insight as a member of Epic’s Community Connect Steering Board, helping shape strategy and best practices for connected health systems nationwide.