Sovereign Health System Leadership Team

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John Hajjar, MD, FACS, MBA

Founder, Chairman, & Chief Executive Officer

Dr. John Hajjar is the Founder, Chairman, and Chief Executive Officer of Sovereign Health System. Following graduation from St. John’s University in Queens, NY, Dr. Hajjar earned his medical degree from the Georgetown University School of Medicine in Washington, DC, in 1981, and then completed his surgical and urological training at New York University Medical Center in Manhattan.

After conducting research into the genetics of renal cancer following residency, Dr. Hajjar entered the private practice of urology in northern New Jersey in 1987. In 1992, he established one of the first ambulatory surgery centers in New Jersey. This center served as the prototype for the many ambulatory surgical centers in New York, New Jersey, and Florida now operated or under development.

Today, Dr. Hajjar devotes all of his professional energies to the growth of Sovereign Health System, a community healthcare system providing people in New Jersey and New York with clinical expertise and state-of-the-art technology.

Glenn A. Gmyrek, MD

Chief Medical Officer

Dr. Glenn A. Gmyrek is a board-certified urologist who serves as Chief Medical Officer. In this capacity, Dr. Gmyrek draws on his deep interest in innovative best practices and evidence-based medicine to enhance patient care.

An active clinician, Dr. Gmyrek sees patients at offices in Fair Lawn and Wayne, NJ, and is affiliated with Hackensack University Medical Center and Valley Hospital. His research on topics ranging from the molecular basis of metastatic prostate cancer to surgical techniques for treating endocrine-related conditions has been published in a number of peer-reviewed medical journals.

Dr. Gmyrek is a graduate of Yale University. He received his medical degree from Columbia University College of Physicians and Surgeons, and completed his urology residency at New York Presbyterian Hospital.

Danielle Sadati

Vice President, Practice Management

Danielle Sadati, Vice President, Practice Management has over 20 years of healthcare management experience. Danielle has overall P&L responsibility for Sovereign Medical Group and its 35 locations. She and her team manage the administrative functions for Sovereign’s multispecialty medical group which requires coordinating revenue cycle management support, supervising all clinical and non-clinical staff, and liaising with the Company’s corporate finance, human resource, systems, and facilities teams. Danielle, along with Sovereign’s CMO, chairs Sovereign’s Medical Advisory Committee. She also has primary responsibility for physician-related business development and marketing.

Earlier in her career, Danielle held leadership positions in Practice Management and Human Resources and managed billing, both for ambulatory surgery centers and the medical group.