Dennis Grewal, DO
NPI 1538556592ActiveIndividual· Internal Medicine, Cardiovascular Disease· Santa Ana, CA
Internal Medicine, Cardiovascular Disease (DO) with Cardiology Specialists of Orange County, practicing in Santa Ana, California. Their prescriptions cost Medicare Part D more than their services did: $312,218 for 1,611 claims, against $73,303 paid for services in 2024. Shockwave Medical, Inc was the largest of 13 companies reporting payments in 2025, $1,891 in all, mostly food and beverage. Lists Hoag Memorial Hospital Presbyterian and 3 other hospitals as hospital affiliations.
Overview
| NPI | 1538556592 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | DO |
| Sole proprietor | No |
| NPI issued | Apr 16, 2015 |
| Last updated in NPPES | Apr 7, 2025 |
| Certified by provider | Apr 7, 2025 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Cardiovascular Disease Primary | 207RC0000X | 15476 | CA |
| Internal Medicine | 207R00000X | 20A15476 | CA |
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) (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 892 |
|---|---|
| Services billed | 1,430 across 46 procedure codes |
| Paid by Medicare | $73,303 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,611 · 3,832 30-day fills |
|---|---|
| Patients | 337 |
| Total drug cost | $312,218 |
| Generic share | 81% of claims |
Education and affiliations
| Graduation year | 2015 |
|---|---|
| Medicare specialty | Cardiovascular Disease (Cardiology) |
| Telehealth | Offers telehealth |
Medical group
- Cardiology Specialists of Orange CountySanta Ana, CA · 9 clinicians
Hospital affiliations
- Hoag Memorial Hospital PresbyterianNewport Beach, CA
- Hoag Orthopedic InstituteIrvine, CA
- Providence St. Joseph HospitalOrange, CA
- Uci Health-OrangeOrange, CA
Industry payments (Open Payments)
- 2025$1,891 · 32 payments from 13 companies
- 2024$1,718 · 15 payments from 6 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Shockwave Medical, Inc | $1,055 | 6 |
| Biotronik Inc. | $263.35 | 2 |
| Kestra Medical Technology Services, Inc. | $92.66 | 2 |
| Zoll Services LLC (A/K/A Zoll Lifecor Corp) | $79.69 | 5 |
| Bayer Healthcare Pharmaceuticals Inc. | $71.16 | 3 |
What the 2025 payments were for
- Food and Beverage$1,891 · 32 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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