Mount Sinai Brooklyn is led by a distinguished staff of physicians and hospital administrators, committed to providing the Brooklyn community with the safest and highest quality of care.

Our leaders adhere to the Mount Sinai tradition of excellence, inspiring physicians, nurses and staff to strive for safe, quality, and compassionate patient care. Our leadership team is comprised of the following hospital professionals. 

Hospital Leadership

Scott Lorin, MD, President, Chief Operating Officer

Dr. Lorin was named Chief Medical Officer of Mount Sinai Brooklyn in 2014 and Chief Operating Officer in 2016. During his tenure, the hospital achieved a Get With the Guidelines®-Stroke Gold Plus award, turned in top-decile performance in New York State’s sepsis care initiative, and was among the state’s leaders in reducing C. difficile rates. Mount Sinai Brooklyn also significantly reduced its mortality and readmission rates. As COO, Dr. Lorin led a successful 2017 survey by The Joint Commission; the deployment of EPIC in the Emergency Department; the completion of a new lobby, infusion center, and pharmacy; the invigoration of clinical programs such as thoracic surgery, critical care, and interventional radiology; and the introduction of a new robotic surgery program.

Dr. Lorin joined the Mount Sinai Health System as an intern in Internal Medicine in 1995 after completing his MD at the Sackler School of Medicine in Tel Aviv, Israel. He completed a residency in Internal Medicine and a fellowship in Pulmonary and Critical Care Medicine at The Mount Sinai Hospital and became an attending physician there in 2001. He also holds an MBA from New York University’s Stern School of Business.

Peter Shearer, MD, Chief Medical Officer

Dr. Shearer joined The Mount Sinai Hospital in 1998 as an attending physician within the Department of Emergency Medicine and was appointed Assistant Professor in Emergency Medicine in 2000. As Program Director of the Emergency Medicine residency from 2006 to 2013, he expanded it from a two-to-four-year postgraduate program to a full four-year program with 60 residents. Additionally, he helped to integrate a novel quality review program for all residents. He has held positions on the Graduate Medical Education Committee, the Admissions Committee, and the Subcommittee on Residency Training and Cultural Competency within the Icahn School of Medicine at Mount Sinai.

Since 2014, Dr. Shearer has been the Medical Director of the Emergency Department at The Mount Sinai Hospital. Along with a strong team of administrative and nursing leaders he rolled out the current "split flow" process, which has reduced the walk-out rate of the emergency department to below the national average and achieved a door-to-provider time that is more than twice as fast as that of other large New York City hospitals. Dr. Shearer has been a fundamental partner in the successes of the sepsis, comprehensive stroke, ST-segment elevation myocardial infarction (STEMI), and heart failure programs at The Mount Sinai Hospital.

Beyond the Emergency Department, Dr. Shearer has been the Root Cause Analysis Chair within The Mount Sinai Hospital Office for Excellence in Patient Care and the Chair of the Credentials Committee of The Mount Sinai Hospital since 2016. These skills will serve him well as he takes on the role of Chief Medical Officer at Mount Sinai Brooklyn.

Dr. Shearer earned his medical degree from the University of Massachusetts Medical School. He completed an internship and residency in Emergency Medicine at the Boston Medical Center.

Linda Valentino, MSN, RN, NEA-BC, Vice President, Chief Nursing Officer, Nursing and Patient Care Services

Linda Valentino, MSN, RN, NEA-BC, is the Vice President, Chief Nursing Officer and Nursing and Patient Care Services for Mount Sinai Brooklyn. In this role, Linda is responsible for overseeing clinical and administrative operations for Patient Care Services. Additionally, her focus is on staff and leadership development, improving quality and patient experience outcomes, and transforming the work environment through staff engagement. 

Linda has more than 25 years of health care experience in a variety of roles. She has held several positions such as Director of Nursing and Patient Care Services, positions in a variety of clinical nursing specialties including Neuroscience, Psychiatry, Medical/Surgical, and Rehabilitation Services.

Linda is recognized as an outstanding leader in her field with a strong record of accomplishments and depth of expertise in care management, transitions of care, and case management. As a transformational leader, she has planned and implemented innovative programs such as multi-hospital system shared governance structures, advanced practice nursing models, and standards of professional practice including clinical research and Magnet Nursing designation.

Marisa Ognibene, Vice President of Human Resources and Administration

A graduate of St. Francis College with a degree in Healthcare Administration, Marisa is a dedicated HR professional with over 25 years of hospital experience. During the course of her career she has managed a full spectrum of Human Resources programs, services and functions. A tireless advocate for the employees of Mount Sinai Brooklyn, Marisa has done extensive work to reinforce high standards of customer service, proactively advance labor management partnership, while collaborating with colleagues at all levels and across disciplines to improve patient experience. Marisa collaborates with leadership to promote Mount Sinai’s standard of excellence and values through workforce, labor and talent initiatives.  

Medical Leadership

  • Chaim Bernstein, MD, Physician in Chief 
  • Stephen Teitelbaum, MD, System Medical Director of CDQI, Deputy CMO, Honorary Chief of Urology
  • Paul Wein, MD, President of the Medical Staff
  • Lucy Cannizzaro, Associate Director of Administration & Director of Pharmacy, Director of Regulatory Affairs
  • Vadim Leyko, Associate Director of Hospital Operations, Director of Respiratory Care