Denisa Hagau, M.D.
NPI 1861703910ActiveIndividual· Internal Medicine, Cardiovascular Disease· Mason City, IA
Internal Medicine, Cardiovascular Disease (M.D.) with North Iowa Mercy Clinics and 2 other groups, practicing in Mason City, Iowa. Their prescriptions cost Medicare Part D more than their services did: $1,060,410 for 6,344 claims, against $88,070 paid for services in 2024. Zoll Services LLC (A/K/A Zoll Lifecor Corp) was the largest of 7 companies reporting payments in 2025, $182.24 in all, mostly food and beverage. Lists Hancock County Health System and 4 other hospitals as hospital affiliations.
Overview
| NPI | 1861703910 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Jun 23, 2010 |
| Last updated in NPPES | Jun 16, 2026 |
| Certified by provider | Jun 16, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Cardiovascular Disease Primary | 207RC0000X | MD-43219 | IA |
| Internal Medicine, Cardiovascular Disease | 207RC0000X | ME167219 | FL |
| Internal Medicine, Cardiovascular Disease | 207RC0000X | 43219 | IA |
| Internal Medicine | 207R00000X | LP01915 | RI |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Nov 10, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 11, 2026 | No match | — |
| New York OMIG · Nov 11, 2026 | No match | — |
| Ohio Medicaid · Nov 11, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 11, 2026 | No match | — |
| Washington HCA · Nov 11, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Cardiovascular Disease (Cardiology) (FL); Practitioner - Cardiovascular Disease (Cardiology) (IA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 1,331 |
|---|---|
| Services billed | 2,032 across 35 procedure codes |
| Paid by Medicare | $88,070 |
Part D prescriptions in 2024
| Prescriptions (claims) | 6,344 · 15,619 30-day fills |
|---|---|
| Patients | 1,031 |
| Total drug cost | $1,060,410 |
| Generic share | 83% of claims |
Education and affiliations
| Graduation year | 2006 |
|---|---|
| Medicare specialty | Cardiovascular Disease (Cardiology) |
Medical groups
- North Iowa Mercy ClinicsMason City, IA · 302 clinicians
- Kossuth Regional Health CenterAlgona, IA · 25 clinicians
- Palo Alto County HospitalEmmetsburg, IA · 23 clinicians
Hospital affiliations
- Hancock County Health SystemBritt, IA
- Kossuth Regional Health CenterAlgona, IA
- Mercyone North Iowa Medical CenterMason City, IA
- Mitchell County Regional HealthOsage, IA
- Palo Alto County HospitalEmmetsburg, IA
Industry payments (Open Payments)
- 2025$182.24 · 11 payments from 7 companies
- 2024$355.87 · 14 payments from 6 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Zoll Services LLC (A/K/A Zoll Lifecor Corp) | $63.94 | 4 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | $32.32 | 2 |
| E.R. Squibb & Sons, L.L.C. | $21.16 | 1 |
| Novartis Pharmaceuticals Corporation | $18.05 | 1 |
| Bayer Healthcare Pharmaceuticals Inc. | $16.94 | 1 |
What the 2025 payments were for
- Food and Beverage$182.24 · 11 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All Internal Medicine, Cardiovascular Disease providers in Iowa →