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NATALYA RUBEN GRIGORYAN MD
NPI 1811485394
Emergency Medicine in West Hills, CA

Active since April 30, 2018PECOS EnrolledAccepts Medicare Assignment
7300 MEDICAL CENTER DR, WEST HILLS, CA 91307(818) 676-4000 Get Directions Write a Review

NPPES record last updated: July 2, 2025. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: Jul 2, 2025, Aug 15, 2022, Apr 30, 2018 (3 updates tracked since 2018).

About Natalya Ruben Grigoryan Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

NATALYA RUBEN GRIGORYAN MD (NPI 1811485394) is an individual emergency medicine provider in West Hills, California, licensed in California (A174112) and active in the NPI registry since April 2018. She is enrolled in Medicare PECOS, is affiliated with Ottumwa Regional Health Center, and is a graduate of Other (2016).

NPPES Registry Identity

NPI1811485394
Entity TypeIndividualFemale
Primary Taxonomy207P00000X
Provider Legal NameNATALYA RUBEN GRIGORYANCredential: MD
Location Address7300 MEDICAL CENTER DRWest Hills, CA 91307-1902
Mailing Address7300 Medical Center DrWest Hills, CA 91307-1902 · (818) 676-4000
Phone(818) 676-4000
Sole ProprietorYes
Medical School CMSOtherGraduated 2016
Enumeration DateApril 30, 2018
Last NPPES UpdateJuly 2, 20253 updates tracked since enumeration
NPPES CertifiedJuly 2, 2025
✔ NPI 1811485394 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
Licenses✔ Licensed in CA · A174112✔ Licensed in IA · MD-54985
Definition
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.
7300 MEDICAL CENTER DR, West Hills, CA 91307
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Arkansas Blue Cross and Blue Shield, Health Advantage, Octave and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Natalya Ruben Grigoryan Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID8426447731
PECOS Enrollment IDI20211108001078, I20250709002207, I20250917002714
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

9

Medicare enrollment records show Natalya Grigoryan reassigns Medicare billing to 9 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Southern California Permanente Medical Group
3.2 mi
Health Maintenance Organization
5601 DE SOTO AVE
Woodland Hills, CA 91367
  • Reassigned Medicare billing, California enrollment
  • 13,921 clinicians in this Medicare group
NPI 1952333478 (818) 719-2000
California Mobile Medical Group Inc
22 mi
Family Medicine
130 N BRAND BLVD STE 208
Glendale, CA 91203
  • Reassigned Medicare billing, California enrollment
  • 18 clinicians in this Medicare group
NPI 1588439061 (818) 945-6003
Mobile Medical Group Inc
22 mi
Family Medicine
130 N BRAND BLVD STE 301
Glendale, CA 91203
  • Reassigned Medicare billing, California enrollment
  • 20 clinicians in this Medicare group
NPI 1487169660 (818) 945-6003
Team Physicians Of Southern California Medical Group, Inc.
104 mi
Emergency Medicine
4002 VISTA WAY
Oceanside, CA 92056
  • Reassigned Medicare billing, California enrollment
  • 140 clinicians in this Medicare group
NPI 1225499015 (925) 924-1600
Team Physicians Of Northern California Medical Group Inc
303 mi
Emergency Medicine
5000 HOPYARD RD, SUITE 100
Pleasanton, CA 94588
  • Reassigned Medicare billing, California enrollment
  • 202 clinicians in this Medicare group
NPI 1649692716 (925) 924-1600
Emergency Services Of Iowa LLC
1,508 mi
Emergency Medicine
1001 PENNSYLVANIA AVE
Ottumwa, IA 52501
  • Reassigned Medicare billing, Iowa enrollment
  • 46 clinicians in this Medicare group
NPI 1477017663 (641) 684-2341
Southeastern Emergency Physicians LLC
1,952 mi
Emergency Medicine
989 MEDICAL PARK DR
Maysville, KY 41056
  • Reassigned Medicare billing, Arkansas enrollment
  • 310 clinicians in this Medicare group
NPI 1356379382 (606) 759-5311
Health Care Alliance, Inc.
2,099 mi
Emergency Medicine
105 S EISENHOWER DR
Beckley, WV 25801
  • Reassigned Medicare billing, West Virginia enrollment
  • 183 clinicians in this Medicare group
NPI 1730128760 (304) 256-6600
Greenbrier Emergency Services, Inc.
  • Reassigned Medicare billing, West Virginia enrollment
  • 207 clinicians in this Medicare group
No phone listed

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 15

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Physician or allowed practitioner supervision of a patient receiving medicare-covered services provided by a participating home health agency (patient not present) requiring complex and multidisciplinary care modalities involving regular physician or allow G0181
This service involves a physician overseeing your care while you receive Medicare-covered services from a home health agency. The care you're receiving is complex and involves various disciplines. The physician isn't physically present but regularly supervises your treatment to ensure optimal health outcomes.
5,759 services1,403 patients
Physician or allowed practitioner certification for medicare-covered home health services under a home health plan of care (patient not present), including contacts with home health agency and review of reports of patient status required by physicians and G0180
This is a service where a doctor or authorized practitioner certifies that you require Medicare-covered home health services. They will communicate with the home health agency and review reports on your health status to ensure you receive appropriate care. This does not involve an in-person visit.
1,283 services1,109 patients
Physician or allowed practitioner re-certification for medicare-covered home health services under a home health plan of care (patient not present), including contacts with home health agency and review of reports of patient status required by physicians a G0179
This procedure involves a doctor or approved practitioner reviewing your health status and re-certifying your need for Medicare-covered home health services. It includes communication with the home health agency and assessment of your health reports, even when you're not physically present.
1,194 services1,012 patients
Education and training to self measure blood pressure 99473
Education and training to self-measure blood pressure involves teaching you how to use a home blood pressure monitor correctly. You'll learn how to position the cuff, when and how often to take readings, and how to interpret and record the results. This empowers you to manage your health.
891 services664 patients
Residence visit for established patient with moderate level of medical decision making, per day, if using time, at least 40 minutes 99349
An established patient home visit is a medical appointment conducted at your home, typically lasting around 40 minutes. This service is ideal for patients who may find it difficult to travel to a healthcare facility. During this visit, a healthcare professional will evaluate your health status, manage your care, and answer any health-related questions you may have.
805 services600 patients
Advance care planning, first 30 minutes 99497
Advance care planning is a process where you discuss your healthcare preferences with your doctor. This conversation, lasting up to 30 minutes, helps ensure your wishes are respected if you're unable to communicate them in the future. It's about your care, your way.
553 services465 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Ottumwa Regional Health Center

Acute Care Hospitals · Ottumwa, IA
2/5 CMS rating
OwnershipProprietary
CMS Certification Number160089
Location1001 E PennsylvaniaOttumwa, IA 52501 · Wapello County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91307 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$96.36 typical visit price
range $62.96 – $187.60
Typical copayment $24.09 (range $15.74 – $46.90)
Most-billed visit code 99203
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

TAHO MEDICAL GROUP
Hospitalist
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 641-9289
ROSMIR ROSETA VILLALUZ FNP
Nurse Practitioner
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000
PHILIP LUU M.D.
Radiology (Diagnostic Radiology)
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4100
KIARASH ROWHANIAN M.D.
Emergency Medicine
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000
WEST HILLS HOSPITAL
General Acute Care Hospital
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000
AARON JAMESON MUELLER MD
Emergency Medicine
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000
GARY SINDELL M.D.
Emergency Medicine
7300 MEDICAL CENTER DR, EMERGENCY DEPARTMENT
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000
RENUKA THAKUR
Nurse Practitioner (Family)
7300 MEDICAL CENTER DR
WEST HILLS, CA 91307
Los Angeles County (818) 676-4000

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Natalya Grigoryan's NPI number?

The NPI number for Natalya Grigoryan is 1811485394. It was assigned to this individual provider in the NPPES registry on April 30, 2018.

Where is Natalya Grigoryan located?

Natalya Grigoryan practices at 7300 Medical Center Dr, West Hills, CA 91307. The listed phone number is (818) 676-4000.

What is Natalya Grigoryan's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Is Natalya Grigoryan enrolled in Medicare?

Yes. Natalya Grigoryan is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organizations bill Medicare for Natalya Grigoryan's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Natalya Grigoryan reassigns Medicare benefits to 9 organizations: Southern California Permanente Medical Group (Woodland Hills, CA), California Mobile Medical Group Inc (Glendale, CA), Mobile Medical Group Inc (Glendale, CA), Team Physicians Of Southern California Medical Group, Inc. (Oceanside, CA), Team Physicians Of Northern California Medical Group Inc (Pleasanton, CA) and 4 more organizations, listed in the Medicare section above. Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Natalya Grigoryan's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Natalya Grigoryan accept?

Health plans from Arkansas Blue Cross and Blue Shield, Health Advantage, Octave and Wellmark Health Plan of Iowa, Inc. list Natalya Grigoryan as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Natalya Grigoryan affiliated with any hospitals?

According to CMS data, Natalya Grigoryan is affiliated with Ottumwa Regional Health Center.

When was this NPI record last updated?

The NPPES record for Natalya Grigoryan was last updated on July 2, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.