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Interventional Cardiology

Stephen A. Mezzafonte, MD

Works at hospitals in Bethpage, NY · West Islip, NY · Rockville Centre, NY … · New York

Summary

Dr. Stephen A. Mezzafonte, MD is an interventional cardiologist at 100 Port Washington Blvd, Roslyn, NY 11576. Phone: (516) 484-6777. Accepts Medicare assignment. In 2024, Stephen A. Mezzafonte had 2,507 Original Medicare patients and 7,467 services. NPI 1649443649. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Stephen A. Mezzafonte, 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 Stephen A. Mezzafonte accept Medicare assignment?
Yes. Medicare's clinician data says Stephen A. Mezzafonte 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 Stephen A. Mezzafonte see?
In 2024, CMS data shows 2,507 Original Medicare patients and 7,467 services for Stephen A. Mezzafonte. This counts Original Medicare only and measures volume, not quality.
What is Stephen A. Mezzafonte's NPI number?
1649443649. 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 Stephen A. Mezzafonte, 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 patients2,507
Services billed to Medicare7,467
Different services or procedures51
Participating Medicare providerYes
Average age of these patients76

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)1,862 services
  2. Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)1,343 services
  3. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)1,056 services
  4. Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (93000)792 services
  5. Ultrasound of heart with color-depicted blood flow, rate, direction and valve function (93306)785 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%
  • Ischemic heart disease65%
  • Arthritis54%
  • Atrial fibrillation36%
  • Diabetes35%

Hospitals where Stephen A. Mezzafonte works

Medicare's Facility Affiliation Data lists Stephen A. Mezzafonte 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.

  • Chsli St Joseph HospitalBethpage, NY · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 330332
  • Good Samaritan Hospital Medical CenterWest Islip, NY · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 330286
  • Mercy Medical CenterRockville Centre, NY · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 330259
  • St Catherine of Siena HospitalSmithtown, NY · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 330401
  • St Francis Hospital - The Heart CenterRoslyn, NY · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 330182

Practice locations

Addresses where Stephen A. Mezzafonte is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 8; the Medicare profile lists all.

Group practices

Medicare enrollment lists Stephen A. Mezzafonte as a member of this group (CMS data updated October 2, 2026).

  • CHS Physician Partners PC743 clinicians in the group

Specialties

Find other Interventional Cardiology doctors in New York →

Other interventional cardiologists in Roslyn

Clinicians with the same Medicare primary specialty in Roslyn, NY — not a recommendation.

All interventional cardiologists in Roslyn →

Other clinicians in CHS Physician Partners PC

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

Clinician information

CredentialMD
Medical schoolNew York University School Of Medicine
Graduation year2002 (24 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1649443649
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians