Quick answers
- Does Juan J. Nieves-Rivera accept Medicare assignment?
- Yes. Medicare's clinician data says Juan J. Nieves-Rivera 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 Juan J. Nieves-Rivera see?
- In 2024, CMS data shows 104 Original Medicare patients and 434 services for Juan J. Nieves-Rivera. This counts Original Medicare only and measures volume, not quality.
- What is Juan J. Nieves-Rivera's NPI number?
- 1588929624. 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 Juan J. Nieves-Rivera, 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 | 104 |
|---|---|
| Services billed to Medicare | 434 |
| Different services or procedures | 18 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (93000)131 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)109 services
- Ultrasound of heart with color-depicted blood flow, rate, direction and valve function (93306)58 services
- Electrocardiogram (ecg) 2-day continuous with review and report by health care professional (93224)29 services
- Ultrasound of both sides of head and neck blood flow (93880)29 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%
- Diabetes63%
- Arthritis50%
- Chronic kidney disease40%
- Ischemic heart disease25%
Hospitals where Juan J. Nieves-Rivera works
Medicare's Facility Affiliation Data lists Juan J. Nieves-Rivera 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.
- Centro Cardiovascular de Puerto Rico y el CaribeSan Juan, PR · Acute Care Hospital · Emergency services: listed by Medicare · CCN 400124
- Hospital Universitario de AdultosRio Piedras, PR · Acute Care Hospital · Emergency services: listed by Medicare · CCN 400061
Practice locations
Addresses where Juan J. Nieves-Rivera is enrolled with Medicare (CMS data updated October 2, 2026).
- 1 ER Piso, Bo. Monacillos Centro Medico De Puerto RicRio Piedras, PR 00935 (787) 754‑8500
- Ave 65 Infanteria Km 8 Hm, 3 R.d.c.m. Grp Med Intrna HacCarolina, PR 00984 (787) 757‑6420
- Bo Monacillos Centro Medico De Puerto, Hospital Universitario De AdultosRio Piedras, PR 00935 (787) 754‑0101
- Ccpr Primer Piso, 4 Bo. Monacillos Centro Medico De Puerto RiRio Piedras, PR 00935
- Pr 130 Km, 8 Barrio Campo AlegreHatillo, PR 00659 (787) 898‑8777
Group practices
Medicare enrollment lists Juan J. Nieves-Rivera as a member of these groups (CMS data updated October 2, 2026).
- Recinto de Ciencias Medicas247 clinicians in the group
- Puerto Rico Cardiology LLC2 clinicians in the group
Specialties
Find other Cardiovascular Disease (Cardiology) doctors in Puerto Rico →
Other cardiologists in Rio Piedras
Clinicians with the same Medicare primary specialty in Rio Piedras, PR — not a recommendation.
Other clinicians in Recinto de Ciencias Medicas
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2012 (14 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1588929624 |
| 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