Quick answers
- Which hospitals does John M. Williams work at?
- Medicare's official clinician data lists John M. Williams at 5 hospitals: Grady Memorial Hospital, Memorial Health, Mercy Hospital Ardmore, Inc, Mercy Hospital Oklahoma City, Inc and Oklahoma Heart Hospital, LLC. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John M. Williams see patients?
- Medicare's clinician data lists 2 practice locations, including Oklahoma City, OK. Call before your visit to confirm the address.
- What is John M. Williams's specialty?
- Medicare lists Interventional Cardiology as the primary specialty, and also Cardiovascular Disease (Cardiology) and Internal Medicine.
- Does John M. Williams accept Medicare assignment?
- Yes. Medicare's clinician data says John M. Williams 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.
- What is the phone number for John M. Williams?
- (405) 241-3539, as listed in official Medicare / NPI Registry data.
- What is John M. Williams's NPI number?
- 1811984719. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John M. Williams works
Medicare's Facility Affiliation Data lists John M. Williams at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Grady Memorial HospitalChickasha, OK · Acute Care Hospital · CCN 370054
- Memorial HealthLawton, OK · Acute Care Hospital · CCN 370056
- Mercy Hospital Ardmore, IncArdmore, OK · Acute Care Hospital · CCN 370047
- Mercy Hospital Oklahoma City, IncOklahoma City, OK · Acute Care Hospital · CCN 370013
- Oklahoma Heart Hospital, LLCOklahoma City, OK · Acute Care Hospital · CCN 370215
Practice locations
Addresses where John M. Williams is enrolled with Medicare (CMS data updated 2026-10-02).
- 3200 Quail Springs Pkwy, Suite 100Oklahoma City, OK 73134
- 3200 Quail Springs Pkwy, Suite 200Oklahoma City, OK 73134 (405) 241‑3539
Group practices
Medicare enrollment lists John M. Williams as a member of these groups (CMS data updated 2026-10-02).
- Cardiovascular Health Clinic PLLC23 clinicians in the group
- Advanced Cardiovascular Solutions, LLC7 clinicians in the group
Specialties
Other interventional cardiologists in Oklahoma City
Clinicians with the same Medicare primary specialty in Oklahoma City, OK — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Oklahoma College Of Medicine |
| Graduation year | 1992 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1811984719 |
| 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