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DR. NICOLAS ATHANASSIOU M.D.
NPI 1750449831
Anesthesiology in Houston, TX

Active since December 04, 2006PECOS EnrolledAccepts Medicare Assignment
93.5/100
CMS Quality Rating
6565 FANNIN ST STE B452, HOUSTON, TX 77030(713) 441-3620(713) 790-2082 Get Directions Write a Review

NPPES record last updated: July 14, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Jul 14, 2026, Aug 25, 2020 (2 updates tracked since 2020).

About Dr. Nicolas Athanassiou M.d. NPPES

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

DR. NICOLAS ATHANASSIOU M.D. (NPI 1750449831) is an individual anesthesiology provider in Houston, Texas, licensed in Texas (L3914) and active in the NPI registry since December 2006. He is enrolled in Medicare PECOS, is affiliated with Houston Methodist Hospital, and is a graduate of Other (1986).

NPPES Registry Identity

NPI1750449831
Entity TypeIndividualMale
Primary Taxonomy207L00000X
Provider Legal NameDR. NICOLAS ATHANASSIOUCredential: M.D.
Location Address6565 FANNIN ST STE B452Houston, TX 77030-2703
Mailing Address6565 Fannin St Ste B452Houston, TX 77030-2703 · (713) 441-3620 · Fax (713) 790-2082
Phone(713) 441-3620
Fax(713) 790-2082
Sole ProprietorNo
Medical School CMSOtherGraduated 1986
Enumeration DateDecember 4, 2006
Last NPPES UpdateJuly 14, 20262 updates tracked since enumeration
NPPES CertifiedJuly 14, 2026
✔ NPI 1750449831 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAnesthesiologyAllopathic & Osteopathic Physicians
Taxonomy Code207L00000X
License✔ Licensed in TX · L3914
Definition
An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an operation or an obstetric or diagnostic procedure. The anesthesiologist assesses the risk of the patient undergoing surgery and optimizes the patient's condition prior to, during and after surgery. In addition to these management responsibilities, the anesthesiologist provides medical management and consultation in pain management and critical care medicine. Anesthesiologists diagnose and treat acute, long-standing and cancer pain problems; diagnose and treat patients with critical illnesses or severe injuries; direct resuscitation in the care of patients with cardiac or respiratory emergencies, including the need for artificial ventilation; and supervise post-anesthesia recovery.
6565 FANNIN ST STE B452, Houston, TX 77030
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Other Identifiers 3

OtherP00246625TX · Railroad Medicare
Medicaid147621003TX
Medicaid2315269LA

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Oscar Insurance Company.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

Dr. Nicolas Athanassiou M.d. 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 ID7719918747
PECOS Enrollment IDI20050829000984
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 Reassignment

Medicare enrollment records show Nicolas Athanassiou reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

U. S. Anesthesia Partners Of Texas, P.A.,
10 mi
Anesthesiology
1500 CITYWEST BLVD, SUITE 300
Houston, TX 77042
  • Reassigned Medicare billing, Texas enrollment
  • Medicare enrollment name: U S Anesthesia Partners Of Texas, PA
  • 3,804 clinicians in this Medicare group
NPI 1548208564 (877) 361-1809

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 4

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.

Insertion of artery tube for blood sampling or infusion through skin 36620
This procedure involves placing a small tube into an artery, usually in the wrist or elbow, to collect blood samples or administer medication. It's done under local anesthesia and is a common, safe practice.
14 services13 patients
Ultrasound of heart with probe in esophagus, with report 93312
This procedure, called a transesophageal echocardiogram, uses a small probe passed into your esophagus to capture detailed images of your heart. The report provides information about your heart's structure and function.
13 services13 patients
Ultrasound of heart blood flow, valves and chambers 93320
An ultrasound of your heart, also known as an echocardiogram, is a test that uses sound waves to create detailed images of your heart. It helps doctors check the health of your heart's chambers, valves, and blood flow.
13 services13 patients
Ultrasound of heart with color-depicted blood flow, rate and valve function 93325
An ultrasound of the heart, also known as an echocardiogram, uses sound waves to create pictures of your heart. It shows the structure, movement, and blood flow within your heart. This helps assess the heart's health and function, including the valves and rate.
13 services13 patients

Hospital Affiliations CMS Care Compare 2

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

Houston Methodist Hospital

Acute Care Hospitals · Houston, TX
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number450358
Location6565 FanninHouston, TX 77030 · Harris County
Emergency services Birthing friendly

Houston Methodist West Hospital

Acute Care Hospitals · Houston, TX
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number670077
Location18500 Katy FreewayHouston, TX 77094 · Harris County
Emergency services Birthing friendly

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

93.5/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality97.15
Improvement Activities40
Cost83.57

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.

ELIZABETH MARIE KINDER APRN
Nurse Practitioner (Acute Care)
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
ANH TUAN NGUYEN M.D.
Psychiatry & Neurology (Neurology)
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
JAMIE HAUERLAND
Nurse Practitioner (Acute Care)
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
JIAN PAUL AZIMI-BOLOURIAN
Anesthesiology
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
KEVIN PATRICK SMITH RN
Nurse Practitioner (Acute Care)
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
JAMES CURTIS CARTER
Anesthesiology
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
RACHEL BEAUCHAMP HANFORD RN, MSN, ACNP-BC
Nurse Practitioner (Acute Care)
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620
ELIZABETH LEE HERRERA MD
Anesthesiology
6565 FANNIN ST STE B452
HOUSTON, TX 77030
Harris County (713) 441-3620

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 Nicolas Athanassiou's NPI number?

The NPI number for Nicolas Athanassiou is 1750449831. It was assigned to this individual provider in the NPPES registry on December 4, 2006.

Where is Nicolas Athanassiou located?

Nicolas Athanassiou practices at 6565 Fannin St Ste B452, Houston, TX 77030. The listed phone number is (713) 441-3620.

What is Nicolas Athanassiou's specialty?

The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.

Is Nicolas Athanassiou enrolled in Medicare?

Yes. Nicolas Athanassiou 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 organization bills Medicare for Nicolas Athanassiou's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Nicolas Athanassiou reassigns Medicare benefits to U. S. Anesthesia Partners Of Texas, P.A., (Houston, TX). The 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 Nicolas Athanassiou's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Nicolas Athanassiou accept?

Health plans from Oscar Insurance Company list Nicolas Athanassiou 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 Nicolas Athanassiou affiliated with any hospitals?

According to CMS data, Nicolas Athanassiou is affiliated with Houston Methodist Hospital and Houston Methodist West Hospital.

When was this NPI record last updated?

The NPPES record for Nicolas Athanassiou was last updated on July 14, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.