Dr. Nolli Silva Riordan, MD
- Medicare services, 2022
- 21
- Medicare patients, 2024
- 25
- Part D claims, 2024
- 21
- MIPS score, 2024
- 100
- Hospital affiliations
- 2
- Practice address
- 2540 East St, Concord, CA 94520
- Practice phone
- Call (925) 682-8200
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Riordan's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Nolli Silva Riordan is a general surgeon in Concord, California
Dr. Riordan practices at Concord Medical Center in Concord, California, part of John Muir Health.
Dr. Riordan's NPI, 1124110192, was assigned on September 28, 2006. Dr. Riordan graduated from John A. Burns School of Medicine in 1993. Dr. Riordan holds California license G81855.
- NPI
- 1124110192NPI Registry (opens in a new tab)
- Medicare PAC ID
- 3779654710
- NPI enumeration date
- September 28, 2006
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (925) 682-8200
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 59
- Medical school graduation
- 1993
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Nolli Silva Riordan practices at Concord Medical Center in Concord, California
Dr. Riordan's primary practice is Concord Medical Center, at 2540 East St, Concord, CA 94520 in Contra Costa County. The practice phone is (925) 682-8200.
- Concord Medical Center2540 East St, Concord, CA 94520 · Contra Costa CountyPhone(925) 682-8200
Source: Dmand AI Affiliation Data
Dr. Nolli Silva Riordan is affiliated with 4 sites of care and 2 medical groups
Dr. Riordan's primary practice is Concord Medical Center in Concord, California, part of John Muir Health. Dr. Riordan is also affiliated with San Ramon Regional Medical Center. The medical group on file is East Bay Cardiovascular & Thoracic Associates. Dmand AI also links Dr. Riordan to 2 more group practices and clinics and 1 medical group, each named with a free account.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Nolli Silva Riordan's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Riordan practices, 4 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Concord Medical Center | Available with a free account |
| +3 more sites and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across John Muir Health and 6.2K+ hospitals, with verified contacts in the same login.
Dr. Nolli Silva Riordan is one of 2,926 general surgeons in California
Surgery is Dr. Riordan's primary specialty in the NPI Registry, under taxonomy code 208600000X. Dmand AI has Dr. Riordan's licenses on file in 2 states: California and Hawaii.
Specialties and state licenses
- Surgery, CaliforniaPrimary
- Hawaii license
General surgeons near Dr. Riordan
Counts of general surgeons with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Nolli Silva Riordan billed Medicare for 21 services in 2022
CMS data shows 21 Medicare services from Dr. Riordan across 1 procedure code in 2022, for 25 Medicare patients. Medicare paid $1,945 for them. Every service was in a facility, such as a hospital, rather than an office.
Dr. Riordan's Medicare services by type, 2020 to 2022
- 2020
- 2022
- Office and hospital visits
- 2020: 02022: 21
- Surgery
- 2020: 442022: 0100%
Dr. Riordan compared with the California median for general surgeons, 2022
- Dr. Riordan
- California median
- Medicare services
- 21vs 16687% below
- Medicare patients
- 25vs 12179% below
- Part D claims
- 11vs 3468% below
Medians across 2,606 general surgeons in California with Dmand AI profiles that report each measure.
Dr. Riordan's most billed Medicare procedure codes, 2022
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Riordan?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Riordan and other general surgeons in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Nolli Silva Riordan treated 25 Medicare patients in 2024, average age 76
CMS counts 25 Medicare patients who saw Dr. Riordan in 2024. The largest group is 75 to 84, with 13 patients. 75% of them have high blood pressure, and 75% have high cholesterol. Their average risk score is 1.02, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Riordan's median patient age at 74, with 46% women.
Dr. Riordan's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Chronic conditions among Dr. Riordan's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Ischemic heart disease75%
- Atrial fibrillation64%
- Chronic kidney disease48%
- Heart failure48%
- Arthritis44%
- Diabetes44%
Share of Medicare patients with each condition. A patient can have several.
Dr. Riordan's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 74
Patient panel by sex, all payers
- Women46%
- Men54%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Nolli Silva Riordan wrote 21 Medicare Part D claims in 2024
In 2024, Dr. Riordan wrote 21 Medicare Part D claims. 100% of them were for generic drugs. CMS names the drug for 11 of them, across 1 drug with 11 or more claims each, at $82 in total drug cost. In 2018, CMS named 13 claims across 1 drug.
Dr. Riordan's most prescribed drugs by claims, 2019
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Part D claims for drugs CMS names, 2018 to 2019
- 2018
- 2019
- Claims for drugs CMS names
- 2018: 132019: 1115%
Drugs named by CMS: 1 in 2019, 1 in 2018.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
Dr. Nolli Silva Riordan scored 100 out of 100 in Medicare's MIPS program for 2024
CMS publishes a Merit-based Incentive Payment System (MIPS) score of 100 out of 100 for Dr. Riordan for performance year 2024, reported as part of a group. Dr. Riordan accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS counts 16 procedures of coronary artery bypass graft (cabg) by Dr. Riordan, more than 58% of the clinicians it reports for that procedure.
- Accepts Medicare assignment
- Yes
Dr. Riordan's MIPS scores, performance year 2024
- 100of 100Final score
- 95.1of 100Quality
- 100of 100Promoting Interoperability
- 40of 100Improvement Activities
- 79of 100Cost
Each score is out of 100. The final score weighs the categories CMS scored for this clinician.
Where Dr. Riordan ranks in Medicare procedure volume
- Coronary artery bypass graft (CABG)
- 58th percentile16 procedures
CMS ranks each clinician against every clinician it reports for the same procedure category.
Sources: Doctors and Clinicians National Downloadable File (CMS); Clinician Public Reporting: Overall MIPS Performance (CMS), 2024 data, released September 10, 2026; and Doctors and Clinicians Utilization Data (CMS)
For MedTech and pharma teams
Filter 7.4M+ HCPs by Medicare procedures, Part D drugs and Open Payments history, then reach them with verified contacts in one login.
Dr. Nolli Silva Riordan received $347 in industry payments from 2017 to 2025
CMS Open Payments shows 12 general payments to Dr. Riordan from 7 drug and device companies from 2017 to 2025. Food and beverage make up the largest share, 100% of the total. Abbott Laboratories paid the most, $122.
General payments to Dr. Riordan by program year, 2017 to 2025
Companies that paid Dr. Riordan the most, 2017 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Nolli Silva Riordan graduated from John A. Burns School of Medicine
Dr. Riordan graduated from John A. Burns School of Medicine in 1993.
- Medical school
Source: Dmand AI Professional Profile Data
Dr. Nolli Silva Riordan accepts plans from 9 insurance carriers
Dr. Riordan is in network with 9 carriers, including Aetna, United Healthcare and Blue Cross Blue Shield of Massachusetts. Medicare plans come from the most carriers, 7. Check the plan with the practice before a visit.
- Aetna
- United Healthcare
- Blue Cross Blue Shield of Massachusetts
- Blue Cross Blue Shield of Michigan
- HCSC
- Regence Health Plans
- Blue Cross and Blue Shield of Kansas City
- CMS Medicare
- +1 more carriersWith a free account
Plan types Dr. Riordan accepts, by number of carriers
- Medicare7
- PPO6
- HMO3
- EPO2
- POS2
Source: Dmand AI Insurance Network Data
Sources for Dr. Nolli Silva Riordan's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Clinician Public Reporting: Overall MIPS Performance (CMS) (opens in a new tab)Doctors and Clinicians Utilization Data (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Nolli Silva Riordan
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Nolli Silva Riordan's NPI number?
Dr. Nolli Silva Riordan's NPI number is 1124110192. It was assigned on September 28, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Nolli Silva Riordan?
Dr. Nolli Silva Riordan is a general surgeon in Concord, California. The primary specialty in the NPI Registry is Surgery Physician (taxonomy code 208600000X).
Where does Dr. Nolli Silva Riordan practice?
Dr. Riordan practices at 2540 East St, Concord, CA 94520. Dr. Riordan's primary practice is Concord Medical Center in Concord, California, part of John Muir Health. Dmand AI also links Dr. Riordan to 2 group practices and clinics and 1 medical group.
What is Dr. Nolli Silva Riordan's office phone number?
The practice phone on file for Dr. Riordan is (925) 682-8200.
What is Dr. Nolli Silva Riordan's medical license number?
Dr. Riordan holds California license G81855, one of the licenses on file in 2 states.
Which states has Dr. Nolli Silva Riordan been licensed in?
Dmand AI has state licenses on file for Dr. Riordan in California (1995 to 2026) and Hawaii (1997 to 2026).
Which hospitals is Dr. Nolli Silva Riordan affiliated with?
Dr. Riordan practices at Concord Medical Center in Concord, California. Dr. Riordan is also affiliated with San Ramon Regional Medical Center.
What medical group is Dr. Nolli Silva Riordan part of?
Dr. Riordan is linked to East Bay Cardiovascular & Thoracic Associates. Dmand AI links Dr. Riordan to 1 more medical group.
Does Dr. Nolli Silva Riordan accept Medicare?
Yes. CMS data shows Dr. Riordan billed Medicare for 21 services in 2022, and Dr. Riordan accepts Medicare assignment.
What is Dr. Nolli Silva Riordan's MIPS score?
Dr. Riordan's MIPS final score for performance year 2024 is 100 out of 100, reported as part of a group.
Show 7 more questionsShow fewer questions
How many Medicare patients does Dr. Nolli Silva Riordan see?
CMS counts 25 Medicare patients who saw Dr. Riordan in 2024, with an average age of 76.
What services does Dr. Nolli Silva Riordan bill to Medicare?
In 2022, Dr. Riordan's most billed Medicare services were hospital inpatient care (99233).
Where did Dr. Nolli Silva Riordan go to medical school?
Dr. Riordan graduated from John A. Burns School of Medicine in 1993.
What drugs does Dr. Nolli Silva Riordan prescribe most?
In 2019 Medicare Part D data, Dr. Riordan's most prescribed drugs by claims were Hydrocodone-Acetaminophen.
Has Dr. Nolli Silva Riordan received payments from drug or device companies?
CMS Open Payments shows $347 in general payments to Dr. Riordan from 7 companies from 2017 to 2025. The largest total came from Abbott Laboratories.
How long has Dr. Nolli Silva Riordan been practicing?
Dr. Riordan graduated from medical school in 1993, 33 years ago.
What insurance does Dr. Nolli Silva Riordan accept?
Dr. Riordan is in network with 9 carriers, including Aetna, United Healthcare and Blue Cross Blue Shield of Massachusetts. Medicare plans come from the most carriers, 7. Check the plan with the practice before a visit.
Selling to surgery practices?
See general surgeons in California by site of care and group
Find the practices, groups and hospitals they work with, and the right people to contact at each.
- 30 days free
- Self-serve
- No credit card