David Chang, MD
Vascular Surgery · San Jose, CANPI 1265453724
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 100.0% of the total across 16 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. It is spread thinly across 13 manufacturers, the largest accounting for just 18.7% — the pattern of someone who eats at a lot of different presentations. Reporting peaked in 2019 at $448 and has fallen 91.3% since, to $39 in 2025. That places this record below the midpoint for vascular surgery clinicians in CA, where the typical reported total is $3,945.
Across 16 payments — averaging $46.78 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Teva Pharmaceuticals USA, Inc.$140
- AstraZeneca$119
- Endologix LLC$118
- Vifor Pharma, Inc.$111
- Silk Road Medical, Inc.$48
- Abbott$42
- plus $171 from 7 others
What the payments were for
- Food & beverage$749100%
Most of this is food and beverage — typically meals provided during product presentations at a clinic or hospital. Nationally that is the single largest category of reported payments by count.
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
| Company | Payments | Total |
|---|---|---|
| Teva Pharmaceuticals USA, Inc. | 1 | $140 |
| AstraZeneca | 1 | $119 |
| Endologix LLC | 1 | $118 |
| Vifor Pharma, Inc. | 1 | $111 |
| Silk Road Medical, Inc. | 2 | $48 |
| Abbott | 2 | $42 |
| Boston Scientific | 2 | $40 |
| Convatec Inc. | 1 | $28 |
| Medtronic | 1 | $27 |
| Inari Medical, Inc. | 1 | $21 |
| Lemaitre Vascular, Inc. | 1 | $20 |
| Smith+Nephew | 1 | $18 |
| Cardiovascular Systems Inc. | 1 | $17 |
What the payments were tied to
Products named in the reported payments. Only payments of $100 or more are attributed here — the typical reported payment nationally is a meal worth about $16, and listing those product-by-product would be noise.
- AJOVY$140
- LOKELMA$119
- Alto Abdominal Stent Graft System$118
- Veltassa$111
How this compares
$749 in reported general payments places this provider in the 25th percentile of 519 vascular surgery providers in California.
Medicare billing
What this is not: this is the amount Original Medicare Part B allowed for services this provider billed in 2024. It is not their income. It excludes Medicare Advantage — now more than half of all Medicare enrollment — along with Medicaid and all commercial insurance, and it is gross practice revenue before staff, rent, supplies and malpractice premiums. CMS also suppresses any figure covering ten or fewer patients, so low-volume providers appear smaller than they are.
Most prescribed under Part D
| Drug | Claims | Cost to plans & patients |
|---|---|---|
| EliquisApixaban | 25 | $20,634 |
| XareltoRivaroxaban | 21 | $15,288 |
Paid to pharmacies, not to this prescriber.
Other vascular surgery in San Jose
- Son DuongFountain Valley$503K
- Venita ChandraPalo Alto$488K
- Sukgu HanLos Angeles$477K
- Leigh Ann ObanionFresno$469K
- Trevor DerderianRancho Mirage$359K
- Karthikeshwar KasirajanPalo Alto$349K
- Johnathon RolloLos Angeles$337K
- Melissa LojaFairfield$272K
- Jason LeePalo Alto$228K
- John LaneSan Diego$212K
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Billing: Medicare Physician & Other Practitioners, data year 2024. Original Medicare Part B only.
- Identity: NPPES NPI Registry, July 2026.