Doctor profile · Federal record

Dr. Ioannis Mastoris, MD

Advanced Heart Failure and Transplant Cardiology Physician (CMS: Advanced Heart Failure and Transplant Cardiology) · Advanced Heart Failure and Transplant Cardiology Physician · Cardiovascular Disease Physician · Cardiovascular Disease Physician · Boston, MA

  • NPI 1124403209
  • Accepts Medicare
  • 15 yrs in practice
  • Licensed in 2 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
55 Fruit St, Grb 800
Boston, MA 021142696
(617) 643-7972
Additional location
67 Corporate Dr Ste 200
Portsmouth, NH 038012847
(603) 610-8070
Mailing address
Po Box 9142
Charlestown, MA 021299142

Credentials & registration

NPPES · NUCC
NPI registered
July 2015 — 11 yrs on file
Profile last updated
May 1, 2023
Year of graduation
2011 — 15 yrs since
Specialty taxonomy
207RA0001X — NUCC code
State licenses (2)
Massachusetts #291827 · New Hampshire #23750

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1124403209. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
779
Distinct HCPCS
9
Medicare allowed
$102,759
HCPCS Description Services Patients Avg allowed
99215 Established patient office or other outpatient visit, 40-54 minutes 208 116 $193
93000 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 166 100 $16
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 119 43 $126
99291 Critical care, first 30-74 minutes 95 25 $225
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 66 27 $84
G2212 Prolonged office or other outpatient evaluation and management service(s) beyond the maximum required time of the primary procedure which has been selected using total time on the date of the primary service; each additional 15 minutes by the physician or 49 35 $34
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 33 33 $184
99205 New patient office or other outpatient visit, 60-74 minutes 23 23 $240
93505 Biopsy of heart muscle 20 15 $235

In context: peer comparison

Among 6 peers in this city , average services per provider: 98. This provider delivers 7.9× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$579
Transactions
5
Manufacturers
2
Payer (manufacturer) Industry Txns Amount
Impulse Dynamics (USA) Inc. 3 $311.72
Abbott Laboratories 2 $267.13

By nature of payment

Food and Beverage
$579

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
428
Patients
142
Total drug cost
$522,563
Drug Type Claims Patients Total cost
Spironolactone Generic 76 31 $975
Metoprolol Succinate Generic 73 28 $1,949
Entresto (Sacubitril/Valsartan) Brand 51 27 $85,347
Jardiance (Empagliflozin) Brand 50 20 $78,596
Torsemide Generic 31 12 $563
Furosemide Generic 28 12 $123
Farxiga (Dapagliflozin Propanediol) Brand 25 0 $36,788
Eliquis (Apixaban) Brand 24 12 $32,333
Atorvastatin Calcium Generic 22 0 $228
Rosuvastatin Calcium Generic 20 0 $1,208

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Ioannis Mastoris's medical specialty?
Dr. Ioannis Mastoris practices Advanced Heart Failure and Transplant Cardiology Physician in Boston, MA.
Where does Dr. Ioannis Mastoris practice?
Dr. Ioannis Mastoris practices at 55 Fruit St, Boston, MA 021142696. Office phone: 6176437972.
What is Dr. Ioannis Mastoris's NPI?
Dr. Ioannis Mastoris's National Provider Identifier (NPI) is 1124403209, issued by NPPES.
Does Dr. Ioannis Mastoris accept Medicare assignment?
Yes. Dr. Ioannis Mastoris accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Ioannis Mastoris commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99215); Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (HCPCS 93000); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99233). Source: CMS Medicare Physician & Other Practitioners file.