Find a Top Internist Near Me in Smithtown, NY – Book an Appointment Instantly

Dr. David Lau received his Medical Degree and PhD degree in Physiology and Biophysics from NYU School of Medicine.   He completed his entire clinical training in Internal Medicine, Cardiovascular Disease, and Clinical Cardiac Electrophysiology at Columbia University - Presbyterian Medical Center.   Dr. Lau specializes in general cardiology and is an expert at the diagnosis of electrophysiological disorders and management after pacemaker, defibrillator, and remote cardiac monitor implantation.   Dr. Lau has presented his research at national meetings and published extensively in the area of electrophysiology.   He has a particular interest in the management of syncope and palpitations.   Dr. Lau is multi-board certified in Internal Medicine, Echocardiography, Cardiovascular Diseases, and Clinical Cardiac Electrophysiology and is Registered in Vascular Interpretations.

Tak Kwan, MD, FAHA, FACC, FACP, FSCAI, is a board-certified and internationally renowned cardiologist at Chinatown Cardiology, PC, in the Chinatown and Upper West Side areas of New York City, Brooklyn and Flushing, New York. Chief of Cardiology, Lenox Hill Greenwich Village, Northwell Health, Director, Asian Practice Initiatives at Lenox Hill Hospital, Clinical Professor of Medicine/Cardiology, Zucker School of Medicine at Hofstra/Northwell, and President, Chinatown Cardiology, P.C. Dr. Kwan earned his medical degree and completed his residency at the State University of New York Downstate Medical Center. For the past 20 years, Dr. Kwan has been an active member within the Chinese community. He served as the president of the Chinese-American Medical Society. He then went on to establish Chinatown Cardiology in order to assist those in the neighborhood. Due to his generous donations and charitable services for the community, Dr. Kwan was awarded the Ellis Island Medal of Honor in 2010.

Dr. Kwan is now the interventional cardiology director at Mount Sinai West, the catheterization laboratory co-director at Mount Sinai Beth Israel, and the affiliate medical director of international services at Mount Sinai Health. He is affiliated with Mount Sinai Beth Israel, serving as a professor at the Icahn School of Medicine, the executive director of Asian services, and the site program director of interventional cardiology. Besides being directly involved in patient care, Dr. Kwan is also an active participant in clinical research.

Dr. Kwan is recognized internationally as an expert in general and interventional cardiology. Not only is he incredibly skilled, but he is also a pioneer in transradial cardiac catheterization, complex percutaneous coronary intervention, structural heart intervention, and transpedal lower extremity peripheral catheterization. Dr. Kwan is committed to providing only the best treatment available to his patients. Whether the patient is seeking treatment for routine heart disorders or is suffering from more complex symptoms, Dr. Kwan has the experience and skills necessary to ensure that the proper care and attention are provided to every patient at Chinatown Cardiology.

For a highly skilled and knowledgeable cardiologist, make an appointment with Dr. Kwan either online or by phone today.

Arsalan Rehmani, MD, FACC, FSCAI is an Interventional and General Cardiologist at Chinatown Cardiology P.C. Dr. Rehmani completed his residency at BronxCare Health System followed by subspecialty fellowships in cardiology and interventional cardiology at Mount Sinai Morningside Hospital. He is board-certified in multiple subspecialties including Internal Medicine, Cardiovascular Disease, Interventional Cardiology, Adult Echocardiography, Nuclear Cardiology, Endovascular Medicine, and Cardiac CT.



Dr. Rehmani accepts new patients, and he currently provides consultations at various locations in New York City, including the Upper West Side and Chinatown in Manhattan, Queens, Brooklyn, and the Bronx. Dr. Rehmani is multilingual, being fluent in English, Urdu, Hindi, Russian, and Ukrainian.

Dr. Henry Siu earned his Medical Degree from the Sophie Davis School of Biomedical Education/SUNY Downstate Medical Center. He completed his post-graduated training in Internal Medicine at Yale New Haven Hospital, and Cardiology/Interventional Cardiology Fellowship at Thomas Jefferson University Hospital in Philadelphia. 

Dr. Siu has expertise in general cardiology, multi-modality cardiac imaging, and vascular imaging. As an interventional cardiologist, Dr. Siu is highly skilled in cardiac catheterizations and peripheral vascular interventions, and management of complex coronary/valvular heart disease. He has proven experience in private practice and in the academic setting, with focus on providing the highest quality care and most up-to-date diagnostic and treatment strategies. In his free time, Dr. Siu enjoys exercising and playing the piano. Dr. Siu speaks Cantonese, Mandarin, and English.

Michael Liou, MD, FACC, FSCAI, is a skilled, board certified interventional cardiologist practicing at Chinatown Cardiology P.C., which has locations in Flushing, Brooklyn, Chinatown, and the Upper West Side of Manhattan. 

Dr. Liou earned his medical degree from SUNY Stony Brook School of Medicine after completing the prestigious Sophie Davis Biomedical Education Program at CUNY City College. He completed his internship and residency in internal medicine at NYU Langone Medical Center and performed his fellowship training in cardiovascular disease at Beth Israel Medical Center (now known as Mount Sinai Beth Israel) and returned to NYU Langone Medical Center for his advanced interventional cardiology subspecialty fellowship. 

Although he provides care for all cardiovascular conditions, Dr. Liou’s clinical expertise is in performing transradial cardiac catheterization, peripheral endovascular intervention, percutaneous mitral & aortic valvuloplasty, and ASD/PFO closure. He continues to participate in clinical research with a special focus on cardiovascular diseases affecting Asian Americans. 

Dr. Liou is multi-board certified in cardiovascular diseases, echocardiography, nuclear cardiology, and interventional cardiology.

Prashanth Mannam, MD, has over 20 years of experience as an internist and primary care provider. He offers patient-focused care to patients aged 12 and older at Mannam Medical & Wellness in the Soundview neighborhood of The Bronx in New York City. 

Dr. Mannam completed his training in medicine in Madras, India. He earned his medical degree at the Madras Medical College and served his internship at the Madras Medical College General Hospital. 

After spending a year honing his skills as a primary care physician at Kommalapati Nursing Home in Ongole, India, he moved to the United States, where he completed his internal medicine residency at New York’s Montefiore North Medical Center in The Bronx. He has since become a member of the American Medical Association and is board-certified in internal medicine.

Dr. Mannam commits himself to provide personalized medical care to his community. He speaks several languages fluently: English, Spanish, Hindi, Tamil, and Telugu. Dr. Mannam takes his time with each patient, never rushing anyone, and answering questions thoroughly. 

Outside of his practice, Dr. Mannam stays active by playing racquetball and tennis. He also enjoys world music and reading.

Dr. Timothy Jayasundera and his colleague Dr. Marsha Wesley provide a variety of medical services to their patients from offices located in Ozone Park, Brooklyn, and Manhattan, New York. Services range from primary care, annual wellness checkups, and regular health screenings to specialist treatment for cardiovascular issues such as hypertension, high cholesterol, chest pain and shortness of breath.

Dr. Jayasundera completed his medical degree at Ross University School of Medicine and his internship in internal medicine at Robert Wood Johnson University Hospital. He went on to complete his residency at Georgetown University and fellowships in Cardiology and Interventional Cardiology at Drexel University and Mount Sinai Hospital, respectively. Dr. Wesley  completed her medical degree at State University of New York (SUNY) Buffalo School of Medicine and Biomedical Sciences.

Drs. Jayasundera and Welsey are all dedicated to providing the highest quality care to their patients. They offer a warm caring environment to make their patients feel comfortable. The doctors take pride in practicing preventative medicine ensuring that all of their patients maintain and improve their health. In addition to treating various medical conditions Dr. Jayasundera and Dr. Wesley also educate patients on their particular medical diagnosis to ensure that the patient maintains good health and stays within healthy guidelines for vital statistics.

Dr. Jayasundera and Dr. Wesley are currently welcoming new patients and looking forward to building lasting relationships to improve and maintain health. Most major forms of insurance are accepted.

Having a chronic illness that requires regular monitoring, or living with a condition that has yet to be diagnosed, is overwhelming. Men and women in the Yonkers, New York area have relied on Jonas Leibowitz, MD for years. As the city’s longtime trusted endocrinologist, Dr. Leibowitz treats a wide scope of medical issues. His practice, Jonas Leibowitz, MD, is near New York City and Westchester County, New York.

Dr. Leibowitz tackles some of medicines toughest cases in his practice. Dr. Leibowitz graduated from Sophie Davis School of Biomedical Education in New York and completed his Internship and Residency at The Mount Sinai Medical Center.

Dr. Leibowitz continues his education regularly, focusing on new technologies and medications. On the cutting edge of new science, Dr. Leibowitz lectures all over the region to teach other medical professionals how to prescribe medication, and when.

The office of Jonas Leibowitz, MD, is currently accepting new patients. Dr. Leibowitz specializes in hormonal disorders, thyroid issues, diabetes, and all types of endocrine-related diseases, he’s highly skilled at treating almost any type of health concern patients may have. His expert team cares for patients from the diagnosis stage, all the way through establishing a treatment.

Dr. Yung Park guides Elevate Medical’s Certified SPRAVATO® Treatment Center in Midtown Manhattan and Pleasantville, NY. She works with people facing treatment-resistant depression, thoughts of suicide, and feeling emotionally shut down or disconnected.

Her approach is calm, grounded, and human. While she brings years of clinical experience, she starts by simply being present—listening closely, without rushing or trying to fix. She believes real healing begins when people feel safe enough to share what’s true for them, at their own pace.

Instead of steering the conversation toward specific outcomes, Dr. Park creates space for reflection, allowing insights to unfold naturally. She’s more curious than directive, and sees every person not as a problem to solve, but as someone in evolution—finding their way, just as we all are.

When she’s not working, you’ll find her walking in nature, birdwatching, creating poetry—on paper and through gardening—and spending time with her two pups, SaLang and Mandu.

Dr. Marissa T. Santos has more than 25 years of experience as a board-certified internist and aesthetic medicine physician. At her Woodside, New York solo practice, Marissa T. Santos, M.D., Dr. Santos offers a wide variety of care for adult patients, including preventive health care, laser hair removal, CoolSculpting® fat removal, screenings including Pap smear, and many other kinds of care. As a licensed Civil Surgeon, Dr. Santos performs medical immigration exams as well.

Dr. Santos is Patient-Centered Medical Home (PCMH) certified. The PCMH certification is a highly respected one that means a physician is qualified to manage the entire spectrum of patient health needs. If patients need specialists, they’re right on the premises. Dr. Santos maintains local hospital affiliations to be there for her patients at all times,

Having earned her medical degree at the University of Santo Tomas in Manila, Philippines, Dr. Santos then continued her medical education at the State University of New York Downstate Medical Center, the Jersey Shore University Medical Center, and the New York Hospital in Queens. Dr. Santos regularly attends internal medicine conferences so that she can keep her practice up-to-date with the newest advances in medicine.

Dr. Santos speaks Spanish, English, Filipino, and Russian, and she enjoys talking with patients in the language they feel most comfortable speaking. Use the online appointment tool to schedule now, or call for an appointment with Dr. Santos.

Dr. Rafael A. Guillén is an internist in the Bronx, in New York City. As the physician at R. Guillén MD PC, Dr. Guillén offers a wide range of care including allergy care, help with obesity, hepatitis care, diabetes care, cholesterol management, high blood pressure treatment, asthma treatment, and arthritis treatment. R. Guillen MD PC is a Patient-Centered Medical Home, recognized by the National Committee for Quality Assurance for providing coordinated, advanced primary care, ensuring that patients are put in the forefront of their care, and a commitment made for continuous quality improvement. Dr. Guillén offers comprehensive health care for adults in the Bronx area. He’s bilingual in English and Spanish and has also carefully chosen a multi-lingual staff for the convenience of his patients.

Dr. Guillén attended the University Eugenio Maria de Hostos School of Medicine in the Dominican Republic. He completed his residency in Internal Medicine at the Bronx-Lebanon Hospital Center in the Bronx, New York. Dr. Guillén is a Diplomate of the American Board of Internal Medicine, and a Fellow of the American College of Physicians. He is an active member of numerous medical organizations, including the American Medical Association, the American College of Physicians, and the Dominican College of Physicians.

Dr. Guillén and his team look forward to seeing new patients and established patients alike. Contact the office anytime to arrange an appointment.

Henock Saint-Jacques, MD, FACC, is a distinguished cardiologist and head clinician at Harlem Cardiology on Madison Avenue in East Harlem of New York City. Dr. Saint-Jacques is held in high esteem throughout New York City and is a deservedly popular speaker at medical conferences and meetings. He also mentors medical students and postgraduate fellows.

Dr. Saint-Jacques studied for his medical degree at Universidad de Ciencias Medicas (UCIMED) in San Jose, Costa Rica. After graduating, he relocated to New York City for a residency in internal medicine at Cabrini Medical Center, which he completed in 1998, followed by a fellowship in cardiology at the Montreal Heart Institute in Canada. After completing his fellowship in 2001, Dr. Saint-Jacques studied at Duke University School of Medicine in Durham, North Carolina, and achieved cardiovascular disease certification with the American Board of Internal Medicine in 2003.

Dr. Saint-Jacques is a Fellow of the American College of Cardiology, a distinction that recognizes members who have achieved exceptional standards of professional excellence and made a significant contribution to the field of cardiovascular medicine.

Preview Dr. Saint-Jacques Doximity Profile HERE. 

Margaret I. Chustecki, MD, MBA, is a skilled internist at Internal Medicine of Greater New Haven in Hamden, West Haven, and Milford, Connecticut. She is also an assistant clinical professor at Yale School of Medicine. 

Born in Warsaw, Poland, and educated at Warsaw Medical School, Dr. Chustecki completed her internship and residency at Newton Wellesley Hospital and New England Medical Center in Massachusetts. Before joining Yale University as a clinical instructor, Dr. Chustecki started Internal Medicine of Greater New Haven in 2003. 

Since then, the practice has flourished, boasting some of the best internists and providers in the United States. Dr. Chustecki maintains patients at the practice while teaching at Yale School of Medicine. She supervises up-and-coming medical professionals while educating them on the benefits of efficient health care. 

Dr. Chustecki remains active in research, and has contributed to over 55 medical publications. She co-founded Chase Medical Research of Greater New Haven in 2015, and serves as the chief clinical trial investigator.