Our Team

Charles M. Blatt, M.D., F.A.C.C

Charles M. Blatt, MD graduated from the Columbia University College of Physicians and Surgeons in 1978 and completed his residency at Beth Israel Hospital, Boston and his fellowship in Cardiovascular Disease at Brigham and Women’s Hospital. Dr. Blatt is Board Certified in Cardiovascular Disease and Internal Medicine. His clinical work has focused on the management of patients with coronary and valvular heart disease, atrial fibrillation, and the impact of psychological stress upon the heart. He has directed several research projects focusing on the roles of depression and anxiety in coronary artery disease. He is an Assistant Professor of Medicine at Harvard Medical School. Dr. Blatt joined the Lown staff in 1984.

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Dr. Blatt is an outdoorsman and enjoys sailing in the summer months and skiing in the winter. He walks daily as part of routine exercise.

Joel T. Katz, M.D., M.A.C.P

Joel T. Katz, M.D., M.A.C.P graduated from the Johns Hopkins University School of Medicine receiving both MD and MA (biomedical illustration) degrees. He completed his internal medicine residency and chief residency at Brigham and Women’s Hospital and fellowship at the Harvard Longwood infectious diseases fellowship program. He is board certified in internal medicine and infectious diseases.  Dr. Katz has been practicing primary care since 1997, over which period he has been named to the list of “Boston’s Best Doctors” numerous times. He joined the Lown Medical Group as their inaugural primary care physician in 2024.

Administratively, Dr. Katz is the Senior Vice President for Education and the Designated Institutional Official at the Dana-Farber Cancer Institute. Dr. Katz enjoys watercolor and oil painting, visiting art museums, and camping throughout New England with his wife and three adult children.

Alyson Kelley-Hedgepeth, M.D., F.A.C.C

Clinical Director,

Co-director Women's Cardiology Program

Alyson Kelley-Hedgepeth, MD graduated from Boston University Medical School in 2003. She trained in Internal Medicine at Massachusetts General Hospital and completed a Fellowship in Cardiology at Tufts Medical Center. Dr. Kelley-Hedgepeth is Board Certified/Eligible in Cardiovascular Disease and Echocardiography and a Diplomate of the American Board of Internal Medicine. She also works as a clinical-preceptor and is on staff at Harvard Medical School. Dr. Kelley-Hedgepeth has extensive experience in managing coronary artery disease, heart failure, and arrhythmias. Prior to joining the Lown Cardiovascular Group, Dr. Kelley-Hedgepeth worked for almost a decade as a non-invasive cardiologist at a multispecialty medical center. There she developed cardiac disease management programs, including heart failure treatment pathways and a post-hospitalization specialized clinic. Dr. Kelley-Hedgepeth is committed to providing personalized cardiovascular care with an emphasis on subclinical atherosclerotic disease detection, metabolic heath, and cardiac prevention. She specializes in cardiac lifestyle assessment and women’s cardiovascular disease. 

Dr. Kelley-Hedgepeth enjoys spending time outdoors with her husband, kids and dog. She enjoys walking/ hiking and skiing in the White Mountains. Her hobbies also include yoga, reading and traveling with her family.

Dara Lee Lewis, M.D., F.A.C.C

Director of Non-Invasive Testing,

Co-director Women's Cardiology Program

Dara Lee Lewis, MD graduated from Harvard Medical School in 1992. She trained in Internal Medicine and Cardiovascular Disease at Brigham and Women’s Hospital. Prior to joining the Lown Group, she was on the staff of Presbyterian Heart Group in Albuquerque, NM. Dr. Lee Lewis is Board Certified in Cardiovascular Disease, Echocardiography, and Nuclear Cardiology. She is an Instructor in Medicine at Harvard Medical School, and is actively involved in medical education. Her professional interests include cardiac imaging, preventive cardiology, women’s cardiac health, and general cardiology issues including coronary artery disease and valvular heart disease. Dr. Lee Lewis also has a special interest in the management of patients experiencing cardiac symptoms of Lyme disease and POTS (Postural Orthostatic Tachycardia Syndrome). Dr. Lee Lewis joined the Lown staff in June 2013.

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Dr. Lee Lewis is a former college coxswain and varsity field hockey player. Now an avid walker and advocate of a healthy and balanced lifestyle, she has a strong interest in the role of nutrition on overall health. In addition, she emphasizes the importance of a healthy lifestyle and non-pharmacologic therapies in the prevention and management of cardiac disease.

Lilian S. Mahrokhian, M.D.

Beginning April 1, 2025

Lilian S. Mahrokhian, MD, graduated from the Tufts University School of Medicine and completed her residency and internship in internal medicine at Tufts-New England Medical Center. She is Board Certified in Internal Medicine and an Assistant Professor in Medicine at Harvard Medical School. She began her clinical practice at Faulkner Hospital (now Brigham and Women's Faulkner Hospital), where she was recruited to begin a primary care practice within the diverse community of Hyde Park. There, she helped transform an urgent care walk-in clinic to a robust primary care practice, effectively educating patients on the benefits of preventive screening and chronic disease management. As the only female practitioner, she developed a predominantly female patient population and quickly recognized her affinity for women’s health. In 2009 she became part of the primary care team at the Fish Center for Women’s Health, where she continued to pursue her passion for providing high quality, comprehensive women’s healthcare. She joined the Lown Medical Group in 2025.

Dr. Mahrokhian’s interests include preventive health, women’s health and Lifestyle Medicine for exercise, nutrition, sleep, and stress management. She enjoys staying active and spending time with her three kids.

Shmuel Ravid, M.D., M.P.H., F.A.C.C

Shmuel Ravid, MD, MPH, received his MD from the Technion – Israel Institute of Technology in 1982 and Master of Public Health from Harvard University. After training in Internal Medicine and Cardiology in Israel, Dr. Ravid completed fellowships in Cardiovascular Disease (Brigham and Women’s Hospital) and Cardiac Electrophysiology (Lahey Clinic/New England Deaconess Hospital). He is Board Certified in Cardiovascular Disease and Internal Medicine. His clinical and research interests include management of cardiac arrhythmias, atrial fibrillation, and long-term outcomes of coronary artery disease. He is an Associate Professor of Medicine at Harvard Medical School. Dr. Ravid joined the Lown staff in 1987.

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Dr. Ravid is a former Director and President of the Lown Cardiovascular Group, and has a special interest in rhythm disorders.

Harley A. Simeone, M.D.

Beginning April 1, 2025

Harley A. Simeone, MD, graduated from the University of Massachusetts Medical School in 2007. She trained in Internal Medicine at Tufts Medical Center and is Board Certified in Internal Medicine. An Assistant Professor of Medicine at Harvard Medical School, she has been actively involved in medical education throughout her 15 years as a primary care physician. She incorporates wellness and personalized medical plans into her preventative and problem-based patient care. She joined the Lown Medical Group in 2025.

Dr. Simeone’s professional interests include comprehensive preventative care, GI health, and using nutrition and exercise as medicine. She enjoys spending time with her three children, husband, and extended family and can often be found on the sidelines of soccer and baseball fields, regardless of weather. She stays active with hiking, skiing and strength training, and also loves traveling, cooking, and music, as well as cheering on Boston sports teams.

Jonathan Gerbode-Grant, NP

Jonathan Gerbode-Grant has practiced in the Boston area since 2017, caring for thousands of patients with a wide range of healthcare issues. At the Lown Group, his breadth and depth of experience in internal medicine complements the cardiology team, providing patients with an opportunity to receive a full spectrum of services, including acute care, chronic disease management and individualized plans for proactive wellness. Jonathan brings a long-held passion for education, always guided by the goal of compassionately helping people realize their optimal quality of life.

He completed his Masters of Science in Nursing and Family Nurse Practitioner degree at Simmons College in Boston, earned a scholarship at the Schwartz Center for Compassionate Healthcare, and studied at Boston's MGH Institute of Health Professions. An avid cyclist, boater and outdoorsman, he enjoys spending time in the Boston area and on Lake Champlain in Vermont with his wife, two daughters, and rescue Labrador Retriever. Jonathan also leads an online health and wellness group for almost 12,000 fathers across five continents.

Jonathan joined the Lown Group in October 2021.

Alyssa Gramstorff, MSPAS, PA-C

Alyssa Gramstorff, MSPAS, PA-C is a board-certified physician associate from central Massachusetts working in our internal medicine branch alongside Dr. Joel Katz. She graduated with her Master of Science in Physician Assistant Studies from Bryant University in 2021. Since graduating, she has become passionate about primary care and gained ample experience through prior positions. She works diligently to manage a variety of both acute and chronic medical conditions, ranging anywhere from a common cold to chronic diabetes. She is highly focused on maintaining excellent relationships with her patients through open communication and shared decision making.

In her free time, Alyssa enjoys reading, spending time with friends & family, and exploring the city. She joined the Lown Group in October 2024 and is greatly looking forward to her future at the practice.