Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Mark J Seifert, MD

Individual provider Cardiovascular Disease Physician · NPI 1942201694

Mark J Seifert, MD practises Cardiac Electrophysiology in Phoenix, Arizona. Graduated from Johns Hopkins University School of Medicine in 1989, 37 years ago. Practices with Honorhealth Ambulatory, a 625-clinician group and accepts Medicare assignment. Licensed in Arizona.

Years since qualifying
37
Trained at
Johns Hopkins University School of Medicine
Licensed in
AZ
In the registry since
2005
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

9250 N 3rd St Ste 3010
Phoenix, AZ 85020-2425 Not confirmed with CMS for 13 years — call before visiting
Phone: (602) 861-1168
Fax: (602) 861-1763
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Clinical Cardiac Electrophysiology Physician (primary) Taxonomy 207RC0001X · Licence 33429 (AZ)
Cardiovascular Disease Physician Taxonomy 207RC0000X · Licence 33429 (AZ)

Record details

NPI number1942201694
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedAugust 3, 2005
Last updated in NPPESSeptember 13, 2013

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCARDIAC ELECTROPHYSIOLOGY
Also practisesCARDIOVASCULAR DISEASE (CARDIOLOGY), FAMILY PRACTICE
Medical schoolJOHNS HOPKINS UNIVERSITY SCHOOL OF MEDICINE
Graduated 1989 (37 years in practice)
Group practice Honorhealth Ambulatory — 625 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Pacemaker insertion or repair 46 times · 87th percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients897
Services billed 6,102 a service is one billed item, such as a visit, a test or a procedure
Average patient age79

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $2,845 41 payments · a meal or drink at a meeting or visit, not a fee
Consulting Fee $625 1 payment
Compensation for services other than consulting , including serving as faculty or as a speaker at a venue other than a continuing education program $338 1 payment

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

  • Honor Health John C. Lincoln Medical Center Hospital · Phoenix, AZ
  • Honorhealth Deer Valley Medical Center Hospital · Phoenix, AZ
  • Honorhealth Scottsdale Shea Medical Center Hospital · Scottsdale, AZ

Colleagues at Honorhealth Ambulatory

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 625 clinicians in the practice; 12 are shown here.

Other providers in Phoenix