Quick answers
- Does David H. Hsi accept Medicare assignment?
- Yes. Medicare's clinician data says David H. Hsi 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 David H. Hsi see?
- In 2024, CMS data shows 398 Original Medicare patients and 1,347 services for David H. Hsi. This counts Original Medicare only and measures volume, not quality.
- What is David H. Hsi's NPI number?
- 1588616312. 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 David H. Hsi, 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 | 398 |
|---|---|
| Services billed to Medicare | 1,347 |
| Different services or procedures | 31 |
| Participating Medicare provider | Yes |
| Average age of these patients | 77 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)300 services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (93000)241 services
- Ultrasound of heart with color-depicted blood flow, rate, direction and valve function (93306)196 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)118 services
- Telephone medical discussion with physician, 5-10 minutes (99441)100 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%
- Arthritis51%
- Ischemic heart disease50%
- Atrial fibrillation26%
- Diabetes24%
Hospitals where David H. Hsi works
Medicare's Facility Affiliation Data lists David H. Hsi 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.
- Greenwich Hospital Association -Greenwich, CT · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 070018
- Stamford HospitalStamford, CT · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 070006
Practice locations
Addresses where David H. Hsi is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 7; the Medicare profile lists all.
- 1 Hospital PlzStamford, CT 06902 (203) 276‑1000
- 29 Hospital PlzStamford, CT 06902
- 32 Strawberry Hill CtStamford, CT 06902
- 36 Grove StNew Canaan, CT 06840
- 4 Hospital Plz, Suite 102Stamford, CT 06902 (203) 276‑2330
Group practices
Medicare enrollment lists David H. Hsi as a member of this group (CMS data updated October 2, 2026).
- Stamford Health Medical Group Inc444 clinicians in the group
Specialties
Find other Cardiovascular Disease (Cardiology) doctors in Connecticut →
Other cardiologists in Stamford
Clinicians with the same Medicare primary specialty in Stamford, CT — not a recommendation.
Other clinicians in Stamford Health Medical Group Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1983 (43 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1588616312 |
| 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