Individual provider

Nikolaos Diakos, M.D.

Interventional Cardiology Physician Advanced Heart Failure and Transplant Cardiology Physician Cardiovascular Disease Physician Medicare enrolled

Nikolaos Diakos, M.D. is an Interventional Cardiology Physician in Houston, TX, registered under NPI 1659791507. This provider registers 4 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.

Getting there

The practice address on file is 6624 FANNIN ST SUITE 2600, Houston, TX 77030. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

6624 FANNIN ST SUITE 2600, Houston, TX 77030 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
T9668 TX Interventional Cardiology Physician primary
T9668 TX Advanced Heart Failure and Transplant…
271477 MA Cardiovascular Disease Physician
T9668 TX Cardiovascular Disease Physician

Licences are recorded in 2 states: TX, MA. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Interventional Cardiology
PAC ID
8921302167
Enrollment ID
I20221108001396

Medicare enrolment is recorded as approved under the provider type Practitioner - Interventional Cardiology. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 2 states

This provider holds licences in 2 states: Massachusetts and Texas. The practice address on file is in Houston, TX, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

MA Massachusetts
Licence
271477
Specialty
Cardiovascular Disease Physician
Verify with the MA board →
TX Texas practice address
Licence
T9668
Specialty
Interventional Cardiology Physician
Verify with the TX board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Interventional Cardiology covers

An area of medicine within the subspecialty of cardiology, which uses specialized imaging and other diagnostic techniques to evaluate blood flow and pressure in the coronary arteries and chambers of the heart and uses technical procedures and medications to treat abnormalities that impair the function of the cardiovascular system. NUCC Health Care Provider Taxonomy, code 207RI0011X
Allopathic & Osteopathic Physicians Internal Medicine Interventional Cardiology

All registered taxonomy codes

This provider registers 5 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207RI0011X Interventional Cardiology Physician Interventional Cardiology T9668 TX primary
207RA0001X Advanced Heart Failure and Transplant Cardiology Physician Advanced Heart Failure and Transplant Cardiology T9668 TX
207RC0000X Cardiovascular Disease Physician Cardiovascular Disease 271477 MA
207RC0000X Cardiovascular Disease Physician Cardiovascular Disease T9668 TX
390200000X Student in an Organized Health Care Education/Training Program

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1659791507 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateApr 18, 2014
Last updatedMar 20, 2023
StatusActive
Sole proprietorYes
CredentialM.D.
Practice address 6624 FANNIN ST
SUITE 2600
Houston, TX 77030
(713) 790-9401
Fax (713) 790-0353
The last update on file is Mar 20, 2023. Providers are only required to update NPPES when their information changes, so an older date does not necessarily mean the details are wrong — but it is worth a quick call before you travel.

Number check

1659791507 passes the NPI check digit test The final digit 7 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 6 5 9 7 9 1 5 0
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 6 1 9 5 9 2 5 0

Sum = 63 · next multiple of 10 = 70 · check digit = 7 · actual last digit = 7

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1659791507?
NPI 1659791507 is the National Provider Identifier assigned to Nikolaos Diakos, M.D. in Houston, TX. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Interventional Cardiology cover?
An area of medicine within the subspecialty of cardiology, which uses specialized imaging and other diagnostic techniques to evaluate blood flow and pressure in the coronary arteries and chambers of the heart and uses technical procedures and medications to treat abnormalities that impair the function of the…
How do I contact Nikolaos Diakos, M.D.?
The phone number on file with NPPES is (713) 790-9401, last updated Mar 20, 2023. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Nikolaos Diakos, M.D. accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1659791507 a valid number?
Yes. 1659791507 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.