Case Rep Gastrointest Med
Dr. Karthikeyan Viswanathan, DO
NPI1396128336PAC ID6103251442
- Medicare services, 2024
- 27
- Medicare patients, 2024
- 35
- Part D claims, 2024
- 389
- Publications
- 1
- Industry payments
- $90
- Practice address
- 270 Green Vly, Freedom, CA 95019
- Practice phone
- Call (408) 937-9000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Center for Cardiovascular Care a Medical Corporation
Freedom, California
Find Dr. Viswanathan'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. Karthikeyan Viswanathan is an internist in Freedom, California
Dr. Viswanathan practices at Center for Cardiovascular Care a Medical Corporation in Freedom, California.
Dr. Viswanathan's NPI, 1396128336, was assigned on July 8, 2015. Dr. Viswanathan graduated from WesternU College of Osteopathic Medicine of the Pacific in 2014. Dr. Viswanathan holds California license 19044.
NPI and contact details
- NPI
- 1396128336NPI Registry (opens in a new tab)
- Medicare PAC ID
- 6103251442
- NPI enumeration date
- July 8, 2015
- NPI status
- Active
- Practice phone
- (408) 937-9000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 38
- Medical school graduation
- 2014
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Practice Data
Dr. Karthikeyan Viswanathan practices at Center for Cardiovascular Care a Medical Corporation in Freedom, California
Dr. Viswanathan's primary practice is Center for Cardiovascular Care a Medical Corporation, at 270 Green Vly, Freedom, CA 95019 in Santa Cruz County. The practice phone is (408) 937-9000.
- Center for Cardiovascular Care a Medical Corporation270 Green Vly, Freedom, CA 95019 · Santa Cruz CountyPhone(408) 937-9000
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Karthikeyan Viswanathan is affiliated with 5 sites of care and 7 medical groups
Dr. Viswanathan's primary practice is Center for Cardiovascular Care a Medical Corporation in Freedom, California. The medical group on file is KAAJ Healthcare. Dmand AI also links Dr. Viswanathan to 6 more medical groups and 4 group practices and clinics, each named with a free account.
Center for Cardiovascular Care a Medical CorporationPrimary
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Karthikeyan Viswanathan's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Viswanathan practices, 4 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Center for Cardiovascular Care a Medical Corporation | Available with a free account |
| +4 more sites and 6 medical groups | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Karthikeyan Viswanathan is one of 16,751 internists in California
Internal medicine is Dr. Viswanathan's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dmand AI has Dr. Viswanathan's licenses on file in 4 states: California, New York, Arkansas and Northern Mariana Islands.
Specialties and state licenses
- Internal medicine, CaliforniaPrimary
- New York license
- Arkansas license
- Northern Mariana Islands license
Clinical focus
Dmand AI lists acute sinusitis, acute skin infection, atrial fibrillation and flutter, bronchitis, cerebrovascular disease, chronic diabetes, chronic hypertension and chronic kidney disease among the conditions Dr. Viswanathan treats.
Internists near Dr. Viswanathan
Counts of internists with a Dmand AI profile, by place and practice. Each opens the list.
16,751internists in California
4internists in Freedom
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Karthikeyan Viswanathan billed Medicare for 27 services in 2024
CMS data shows 27 Medicare services from Dr. Viswanathan across 2 procedure codes in 2024, for 35 Medicare patients. Medicare paid $162 for them. Every service was in an office.
Medicare services, 202427
Medicare patients35
Paid by Medicare$162
Procedure codes2
Dr. Viswanathan's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Lab and pathology
- 2023: 1882024: 2786%
Dr. Viswanathan compared with the California median for internists, 2024
- Dr. Viswanathan
- California median
- Medicare services
- 27vs 36193% below
- Medicare patients
- 35vs 15177% below
- Part D claims
- 152vs 42164% below
Medians across 15,815 internists in California with Dmand AI profiles that report each measure.
Dr. Viswanathan's most billed Medicare procedure codes, 2024
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. Viswanathan?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Viswanathan and other internists in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Karthikeyan Viswanathan treated 35 Medicare patients in 2024, average age 71
CMS counts 35 Medicare patients who saw Dr. Viswanathan in 2024. The largest group is 65 to 74, with 20 patients. 74% of them have high blood pressure, and 54% have diabetes. 66% are also on Medicaid. Their average risk score is 1.28, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Viswanathan's median patient age at 66, with 56% women.
Medicare patients, 202435
Average age71
Average risk score1.28
Also on Medicaid66%
Dr. Viswanathan's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Viswanathan's Medicare patients by sex, 2024
- Women1954%
- Men1646%
Chronic conditions among Dr. Viswanathan's Medicare patients, 2024
- High blood pressure74%
- Diabetes54%
- High cholesterol54%
- Arthritis37%
- Chronic kidney disease34%
Share of Medicare patients with each condition. A patient can have several.
Dr. Viswanathan's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 66
Patient panel by sex, all payers
- Women56%
- Men44%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Karthikeyan Viswanathan wrote 389 Medicare Part D claims in 2024
In 2024, Dr. Viswanathan wrote 389 Medicare Part D claims for 56 patients. 78% of them were for generic drugs. CMS names the drug for 152 of them, across 6 drugs with 11 or more claims each, at $14,841 in total drug cost. In 2023, CMS named 67 claims across 3 drugs.
Part D claims, 2024389
Drugs named by CMS6
Total drug cost$14,841
Part D patients56
Dr. Viswanathan's Part D claims by kind of drug, 2024
- Generic302 claims78%
- Brand-name and other87 claims22%
Dr. Viswanathan's most prescribed drugs by claims, 2024
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, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 672024: 152127%
Drugs named by CMS: 6 in 2024, 3 in 2023.
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
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Dr. Karthikeyan Viswanathan has 1 publication on record
Dmand AI links 1 paper to Dr. Viswanathan in 2016. Dr. Viswanathan's most frequent co-authors are Nilar Tun and Nu Nwe Tun, MD.
Papers1
Dr. Viswanathan's most frequent co-authors
- Nilar Tun1 shared paper
- Nu Nwe Tun, MD1 shared paper
Recent publications by Dr. Viswanathan
See who Dr. Viswanathan researches with
Physician Network Discovery turns co-authorship, shared hospitals and shared groups into a map of who Dr. Viswanathan works with, so you can find a warm path to the right internists.
Sources: PubMed (National Library of Medicine); and Dmand AI Research Linkage
Dr. Karthikeyan Viswanathan received $90 in industry payments from 2022 to 2025
CMS Open Payments shows 5 general payments to Dr. Viswanathan from 4 drug and device companies from 2022 to 2025. Food and beverage make up the largest share, 100% of the total. Gilead Sciences, Inc. paid the most, $31.
General payments to Dr. Viswanathan by program year, 2022 to 2025
Companies that paid Dr. Viswanathan the most, 2022 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Karthikeyan Viswanathan graduated from WesternU College of Osteopathic Medicine of the Pacific
Dr. Viswanathan graduated from WesternU College of Osteopathic Medicine of the Pacific in 2014.
- Medical school
Source: Dmand AI Professional Profile Data
Dr. Karthikeyan Viswanathan accepts plans from 14 insurance carriers
Dr. Viswanathan is in network with 14 carriers, including Blue Cross Blue Shield of Michigan, United Healthcare and Elevance. PPO plans come from the most carriers, 9. Check the plan with the practice before a visit.
- Blue Cross Blue Shield of Michigan
- United Healthcare
- Elevance
- HCSC
- Aetna
- Blue Cross Blue Shield of Massachusetts
- Regence Health Plans
- Alliant Health Plans
- +6 more carriersWith a free account
Plan types Dr. Viswanathan accepts, by number of carriers
- PPO9
- HMO6
- Medicare5
- EPO3
- POS3
- Medicaid1
Source: Dmand AI Insurance Network Data
Sources for Dr. Karthikeyan Viswanathan'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 | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation 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) |
| Publications, topics and co-authors | PubMed (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage |
| 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. Karthikeyan Viswanathan
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. Karthikeyan Viswanathan's NPI number?
Dr. Karthikeyan Viswanathan's NPI number is 1396128336. It was assigned on July 8, 2015, and it is active in the NPI Registry.
What kind of doctor is Dr. Karthikeyan Viswanathan?
Dr. Karthikeyan Viswanathan is an internist in Freedom, California. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Karthikeyan Viswanathan practice?
Dr. Viswanathan practices at 270 Green Vly, Freedom, CA 95019. Dr. Viswanathan's primary practice is Center for Cardiovascular Care a Medical Corporation in Freedom, California. Dmand AI also links Dr. Viswanathan to 6 medical groups and 4 group practices and clinics.
What is Dr. Karthikeyan Viswanathan's office phone number?
The practice phone on file for Dr. Viswanathan is (408) 937-9000.
What is Dr. Karthikeyan Viswanathan's medical license number?
Dr. Viswanathan holds California license 19044, one of the licenses on file in 4 states.
Which states has Dr. Karthikeyan Viswanathan been licensed in?
Dmand AI has state licenses on file for Dr. Viswanathan in California (2021 to 2027), New York (2018 to 2026), Arkansas (2019 to 2024) and Northern Mariana Islands (2018 to 2022).
What medical group is Dr. Karthikeyan Viswanathan part of?
Dr. Viswanathan is linked to KAAJ Healthcare. Dmand AI links Dr. Viswanathan to 6 more medical groups.
Does Dr. Karthikeyan Viswanathan accept Medicare?
Yes. CMS data shows Dr. Viswanathan billed Medicare for 27 services in 2024.
How many Medicare patients does Dr. Karthikeyan Viswanathan see?
CMS counts 35 Medicare patients who saw Dr. Viswanathan in 2024, with an average age of 71.
What services does Dr. Karthikeyan Viswanathan bill to Medicare?
In 2024, Dr. Viswanathan's most billed Medicare services were lab and pathology test (83036) and lab and pathology test (81003).
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Where did Dr. Karthikeyan Viswanathan go to medical school?
Dr. Viswanathan graduated from WesternU College of Osteopathic Medicine of the Pacific in 2014.
What drugs does Dr. Karthikeyan Viswanathan prescribe most?
In 2024 Medicare Part D data, Dr. Viswanathan's most prescribed drugs by claims were Lisinopril, Atorvastatin Calcium and Farxiga.
Has Dr. Karthikeyan Viswanathan received payments from drug or device companies?
CMS Open Payments shows $90 in general payments to Dr. Viswanathan from 4 companies from 2022 to 2025. The largest total came from Gilead Sciences, Inc.
How long has Dr. Karthikeyan Viswanathan been practicing?
Dr. Viswanathan graduated from medical school in 2014, 12 years ago.
Does Dr. Karthikeyan Viswanathan do research?
Dmand AI links 1 publication to Dr. Viswanathan.
Who does Dr. Karthikeyan Viswanathan publish with?
Dr. Viswanathan's most frequent co-authors are Nilar Tun (1 shared paper) and Nu Nwe Tun, MD (1 shared paper).
What insurance does Dr. Karthikeyan Viswanathan accept?
Dr. Viswanathan is in network with 14 carriers, including Blue Cross Blue Shield of Michigan, United Healthcare and Elevance. PPO plans come from the most carriers, 9. Check the plan with the practice before a visit.
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