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Internal Medicine

Nahum Vishniavsky, MD

Sees patients in Wellesley, MA · Massachusetts

Summary

Dr. Nahum Vishniavsky, MD is an internal medicine doctor at 230 Worcester St, Wellesley, MA 02481. Phone: (781) 431-5200. Accepts Medicare assignment. In 2024, Nahum Vishniavsky had 18 Original Medicare patients and 56 services. NPI 1972555373. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 230 Worcester St, Wellesley, MA 02481 · Directions
  • Phone: (781) 431‑5200
  • Medicare: Accepts Medicare assignment
  • Group practice: Atrius Health Inc
  • Medical school: Virginia Commonwealth University, School Of Medicine · graduated 1976 (50 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Nahum Vishniavsky, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Nahum Vishniavsky accept Medicare assignment?
Yes. Medicare's clinician data says Nahum Vishniavsky 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 Nahum Vishniavsky see?
In 2024, CMS data shows 18 Original Medicare patients and 56 services for Nahum Vishniavsky. This counts Original Medicare only and measures volume, not quality.
What is Nahum Vishniavsky's NPI number?
1972555373. 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 Nahum Vishniavsky, 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 patients18
Services billed to Medicare56
Different services or procedures30
Participating Medicare providerYes
Average age of these patients76

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 cholesterol72%
  • High blood pressure67%

Practice locations

Addresses where Nahum Vishniavsky is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Nahum Vishniavsky as a member of this group (CMS data updated October 2, 2026).

  • Atrius Health Inc1,222 clinicians in the group

Specialties

Find other Internal Medicine doctors in Massachusetts →

Other internal medicine doctors in Wellesley

Clinicians with the same Medicare primary specialty in Wellesley, MA — not a recommendation.

All internal medicine doctors in Wellesley →

Other clinicians in Atrius Health Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolVirginia Commonwealth University, School Of Medicine
Graduation year1976 (50 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1972555373
CorrectionsReport 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

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians