Quick answers
- Which hospitals does Sei Iwai work at?
- Medicare's official clinician data lists Sei Iwai at 5 hospitals: Garnet Health Medical Center, Healthalliance Hospital Marys Avenue Campus, Montefiore St Luke's Cornwall, Phelps Hospital and Westchester Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Sei Iwai see patients?
- Medicare's clinician data lists 8 practice locations, including Valhalla, NY, Kingston, NY and Hawthorne, NY. Call before your visit to confirm the address.
- What is Sei Iwai's specialty?
- Medicare lists Cardiac Electrophysiology as the primary specialty.
- Does Sei Iwai accept Medicare assignment?
- Yes. Medicare's clinician data says Sei Iwai accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- Does Sei Iwai offer telehealth?
- Medicare's clinician data says Sei Iwai offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Sei Iwai?
- (845) 339-3663, as listed in official Medicare / NPI Registry data.
- What is Sei Iwai's NPI number?
- 1033206115. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Sei Iwai works
Medicare's Facility Affiliation Data lists Sei Iwai at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Garnet Health Medical CenterMiddletown, NY · Acute Care Hospital · CCN 330126
- Healthalliance Hospital Marys Avenue CampusKingston, NY · Acute Care Hospital · CCN 330224
- Montefiore St Luke's CornwallNewburgh, NY · Acute Care Hospital · CCN 330264
- Phelps HospitalSleepy Hollow, NY · Acute Care Hospital · CCN 330261
- Westchester Medical CenterValhalla, NY · Acute Care Hospital · CCN 330234
Practice locations
Addresses where Sei Iwai is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 8; the Medicare profile lists all.
- 100 Woods RdValhalla, NY 10595
- 111 Marys Ave, Suite 3Kingston, NY 12401 (845) 339‑3663
- 117 Marys Ave, Suite 102Kingston, NY 12401 (845) 338‑5555
- 19 Bradhurst AveHawthorne, NY 10532
- 575 Hudson Valley AveNew Windsor, NY 12553
Group practices
Medicare enrollment lists Sei Iwai as a member of this group (CMS data updated 2026-10-02).
- Westchester Medical Center Advanced Physician Services PC897 clinicians in the group
Specialties
- Cardiac Electrophysiologyprimary
Other cardiac electrophysiologists in New York
Clinicians with the same Medicare primary specialty in New York — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Columbia University College Of Physicians And Surgeons |
| Graduation year | 1994 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1033206115 |
| 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 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- 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