Warren JohnstonMD
Cardiology·Orange, CA
Warren Johnston, MD is a Cardiology provider in Orange, CA, as of July 2026.
- NPI1427052802
- Registered2005
- Class of1975
Case volumes, referral patterns, and payer mix live in DataLily AI Insights.
Education
Education on record as of August 2026.
Warren Johnston at a glance
- Provider
- Warren Johnston
- Credential
- MD
- Specialty
- Cardiovascular Disease (Cardiology)
- Procedures
- Cardiology CPT codes
- Location
- Orange, CA
- Medical school
- University of Rochester School of Medicine and Dentistry
- Graduated
- 1975
- NPI registered
- 2005
- NPI
- 1427052802
- Snapshot
- July 2026
Identity, specialty, and affiliations change over time. This is not an endorsement, and not clinical, billing, or legal advice. Providers may request corrections at founders@datalilyai.com. Read the DataLily AI data methodology.
Questions
Where does Warren Johnston practice?
Warren Johnston, MD is based in Orange, CA. Affiliations reflect the current DataLily AI snapshot (July 2026) and can change.
What is Warren Johnston's NPI number?
Warren Johnston's National Provider Identifier (NPI) is 1427052802, registered in 2005. Specialty on record: Cardiovascular Disease (Cardiology); credential MD.
Where did Warren Johnston go to medical school?
Warren Johnston, MD attended University of Rochester School of Medicine and Dentistry, graduating in 1975.
How many Cardiology providers in California work at ambulatory surgery centers?
444 Cardiology surgeons and proceduralists in California are affiliated with ambulatory surgery centers in DataLily AI's current snapshot, Warren Johnston among them. The California Cardiology directory lists each one by city with credential, NPI, and center affiliations.
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