Marsden Blois, MD
NPI 1215938683 · Cardiovascular Disease Physician · Boulder, CO
Enrolled with Medicare as Practitioner - Cardiovascular Disease (cardiology) · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marsden Blois, MD is a Cardiovascular Disease Physician provider in Boulder, CO (NPI 1215938683).
Provider details
- NPI number
- 1215938683
- Entity type
- Individual
- Primary specialty
- Cardiovascular Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- DR.0034464 (CO)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
2,007 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 674 | $128 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report Only93010 | 486 | $8 |
| Ultrasound of Heart With Color-Depicted Blood Flow, Rate, Direction and Valve Function93306 | 397 | $67 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 91 | $167 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 56 | $77 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 37 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Empagliflozinbrand: Jardiance | 511 | 157 |
| Metoprolol Succinate | 468 | 154 |
| Atorvastatin Calcium | 454 | 143 |
| Spironolactone | 422 | 147 |
| Torsemide | 305 | 117 |
| Carvedilol | 305 | 90 |
| Apixabanbrand: Eliquis |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$14 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 1760 E Ken Pratt Blvd Ste 205Longmont, CO 80504-5311Phone: (720) 718-8180Fax: (720) 718-5989
Registry dates
- Enumerated
- 2005-08-09
- Last updated
- 2026-02-06
- Certified
- 2026-02-06
Frequently asked questions
- What is Marsden Blois's NPI number?
- Marsden Blois's National Provider Identifier (NPI) is 1215938683, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marsden Blois's specialty?
- Marsden Blois is listed in the NPPES registry with a primary specialty of Cardiovascular Disease Physician (Allopathic & Osteopathic Physicians).
- Where is Marsden Blois located?
- Marsden Blois's practice location on file with NPPES is 4743 Arapahoe Ave, Boulder, CO 80303-1113.
- What is Marsden Blois's phone number?
- The practice phone number listed in the NPPES registry for Marsden Blois is (303) 442-2395.
- Does Marsden Blois accept Medicare?
- Marsden Blois is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marsden Blois's NPI active?
- Yes — Marsden Blois's NPI (1215938683) is active in the NPPES registry as of the last update on 2026-02-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.