Quick answers
- Does Karthi Subbannan accept Medicare assignment?
- Yes. Medicare's clinician data says Karthi Subbannan accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Karthi Subbannan see?
- In 2024, CMS data shows 289 Original Medicare patients and 664 services for Karthi Subbannan. This counts Original Medicare only and measures volume, not quality.
- What is Karthi Subbannan's NPI number?
- 1154443091. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Karthi Subbannan, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 289 |
|---|---|
| Services billed to Medicare | 664 |
| Different services or procedures | 14 |
| Participating Medicare provider | Yes |
| Average age of these patients | 76 |
Most frequent services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)405 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)139 services
- New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)29 services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)29 services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)17 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Arthritis53%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)32%
- Ischemic heart disease31%
- Anxiety27%
Hospitals where Karthi Subbannan works
Medicare's Facility Affiliation Data lists Karthi Subbannan at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Emory Johns Creek HospitalJohns Creek, GA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 110230
- Northside HospitalAtlanta, GA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 110161
- Northside Hospital DuluthDuluth, GA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 110252
- Northside Hospital ForsythCumming, GA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 110005
- Northside Hospital GwinnettLawrenceville, GA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 110087
Practice locations
Addresses where Karthi Subbannan is enrolled with Medicare (CMS data updated October 2, 2026).
- 3330 Preston Ridge Rd, Suite 110Alpharetta, GA 30005 (678) 566‑6995
- 6300 Hospital Pkwy, Suite 300Duluth, GA 30097 (770) 623‑8965
Group practices
Medicare enrollment lists Karthi Subbannan as a member of this group (CMS data updated October 2, 2026).
- NSH Cancer Institute Professional Services G LLC119 clinicians in the group
Specialties
- Hematology/Oncologyprimary
- Hematologyalso
Other hematologist-oncologists in Georgia
Clinicians with the same Medicare primary specialty in Georgia — not a recommendation.
Other clinicians in NSH Cancer Institute Professional Services G LLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1996 (30 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1154443091 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians