Quick answers
- Does Zachary T. Hollis accept Medicare assignment?
- Yes. Medicare's clinician data says Zachary T. Hollis accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Zachary T. Hollis see?
- In 2024, CMS data shows 1,483 Original Medicare patients and 4,168 services for Zachary T. Hollis. This counts Original Medicare only and measures volume, not quality.
- What is Zachary T. Hollis's NPI number?
- 1104142744. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Zachary T. Hollis, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 1,483 |
|---|---|
| Services billed to Medicare | 4,168 |
| Different services or procedures | 76 |
| Participating Medicare provider | Yes |
| Average age of these patients | 79 |
Most frequent services
- Evaluation of single, dual, multiple lead or leadless pacemaker system or implantable defibrillator system, remote up to 90 days (93296)974 services
- Evaluation of single, dual, multiple lead or leadless pacemaker system, remote up to 90 days (93294)705 services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (93000)449 services
- Evaluation of cardiac rhythm monitor system, remote up to 30 days (93298)323 services
- Evaluation of single, dual, or multiple lead implantable defibrillator system, remote up to 90 days (93295)271 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Atrial fibrillation70%
- Ischemic heart disease52%
- Heart failure52%
- Arthritis47%
Hospitals where Zachary T. Hollis works
Medicare's Facility Affiliation Data lists Zachary T. Hollis at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Inova Alexandria HospitalAlexandria, VA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 490040
- Inova Fair Oaks HospitalFairfax, VA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: not listed by Medicare · CCN 490101
- Inova Fairfax HospitalFalls Church, VA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 490063
- Inova Loudoun HospitalLeesburg, VA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 490043
Practice locations
Addresses where Zachary T. Hollis is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 6; the Medicare profile lists all.
- 104 Selma DrWinchester, VA 22601 (540) 678‑2800
- 21785 Filigree Ct, Suite 203Ashburn, VA 20147 (703) 554‑1103
- 3020 Hamaker Ct, Suite 101Fairfax, VA 22031 (703) 289‑9400
- 3300 Gallows RdFalls Church, VA 22042 (703) 776‑4001
- 4320 Seminary Rd, Inova Alex HospAlexandria, VA 22304 (703) 504‑3000
Group practices
Medicare enrollment lists Zachary T. Hollis as a member of these groups (CMS data updated October 2, 2026).
- Inova Health Care Services1,817 clinicians in the group
- Selma Medical Assoc Inc30 clinicians in the group
Specialties
Other cardiac electrophysiologists in Virginia
Clinicians with the same Medicare primary specialty in Virginia — not a recommendation.
Other clinicians in Inova Health Care Services
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Illinois College Of Med (chi/peor/rock/chm-Urb) |
| Graduation year | 2010 (16 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1104142744 |
| 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 October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- 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