Quick answers
- Does Visaharan Sivasubramaniam accept Medicare assignment?
- Yes. Medicare's clinician data says Visaharan Sivasubramaniam accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Visaharan Sivasubramaniam see?
- In 2024, CMS data shows 238 Original Medicare patients and 6,453 services for Visaharan Sivasubramaniam. This counts Original Medicare only and measures volume, not quality.
- What is Visaharan Sivasubramaniam's NPI number?
- 1902801921. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Visaharan Sivasubramaniam, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 238 |
|---|---|
| Services billed to Medicare | 6,453 |
| Different services or procedures | 94 |
| Participating Medicare provider | Yes |
| Average age of these patients | 78 |
Most frequent services
- Advance care planning, first 30 minutes (99497)178 services
- Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes (99221)177 services
- Insertion of needle into vein for collection of blood sample (36415)55 services
- Complete blood cell count (red cells, white blood cell, platelets), automated test and automated differential white blood cell count (85025)52 services
- Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes (99231)41 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Diabetes73%
- Ischemic heart disease58%
- Heart failure53%
- Alzheimer's disease or dementia53%
Hospitals where Visaharan Sivasubramaniam works
Medicare's Facility Affiliation Data lists Visaharan Sivasubramaniam at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Lenox Hill HospitalNew York, NY · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 330119
Practice locations
Addresses where Visaharan Sivasubramaniam is enrolled with Medicare (CMS data updated October 2, 2026).
- 48 Route 25aSmithtown, NY 11787 (631) 751‑3000
- 8616 Jamaica AveWoodhaven, NY 11421 (631) 781‑3000
Group practices
Medicare enrollment lists Visaharan Sivasubramaniam as a member of this group (CMS data updated October 2, 2026).
- North Shore Hematology Oncology Associates PC479 clinicians in the group
Specialties
- Hematology/Oncologyprimary
Other hematologist-oncologists in Smithtown
Clinicians with the same Medicare primary specialty in Smithtown, NY — not a recommendation.
Other clinicians in North Shore Hematology Oncology Associates PC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1994 (32 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1902801921 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians