Doctor profile · Federal record
Dr. Mark O'Connor, M.D.
Cardiovascular Disease Physician (CMS: Cardiovascular Disease (Cardiology)) · Leominster, MA
- NPI 1215297270
- Accepts Medicare
- 14 yrs in practice
- Male
- Group practice
- No sanctions
Practice & contact
- Primary practice
-
100 Hospital RD
Leominster, MA 014532253
(978) 466-2052
fax (978) 466-2085 - Mailing address
-
Po Box 415348
Boston, MA 022415348
Credentials & registration
- NPI registered
- May 2012 — 14 yrs on file
- Profile last updated
- September 10, 2025
- Year of graduation
- 2012 — 14 yrs since
- Specialty taxonomy
- 207RC0000X — NUCC code
- State license (1)
- Massachusetts #277574
- Medicaid
- MA #110103978A
Federal sanctions & exclusions
No sanctions, exclusions or revocations on file
Checked against OIG LEIE on NPI 1215297270. Last verified May 11, 2026.Medicare procedures · 2023
Top services delivered
Total services
3,578
Distinct HCPCS
10
Medicare allowed
$247,300
| HCPCS | Description | Services | Patients | Avg allowed | |
|---|---|---|---|---|---|
93000 |
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report | 856 | 612 | $15 | |
93010 |
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only | 716 | 585 | $8 | |
99214 |
Established patient office or other outpatient visit, 30-39 minutes | 709 | 542 | $132 | |
93306 |
Ultrasound of heart with color-depicted blood flow, rate, direction and valve function | 250 | 241 | $205 | |
99213 |
Established patient office or other outpatient visit, 20-29 minutes | 143 | 106 | $93 | |
93306 |
Ultrasound of heart with color-depicted blood flow, rate, direction and valve function | 130 | 129 | $70 | |
93296 |
Evaluation of single, dual, multiple lead or leadless pacemaker system or implantable defibrillator system, remote up to 90 days | 113 | 64 | $24 | |
99223 |
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | 109 | 104 | $177 | |
93294 |
Evaluation of single, dual, multiple lead or leadless pacemaker system, remote up to 90 days | 83 | 46 | $30 | |
99204 |
New patient office or other outpatient visit, 45-59 minutes | 64 | 64 | $172 |
In context: peer comparison
Among 4 peers in this city , average services per provider: 124. This provider delivers 29× the peer median.Medicare Part D · 2023
Top prescriptions
Total claims
3,123
Patients
1,020
Total drug cost
$704,443
| Drug | Type | Claims | Patients | Total cost |
|---|---|---|---|---|
| Metoprolol Succinate | Generic | 544 | 179 | $15,435 |
| Eliquis (Apixaban) | Brand | 428 | 118 | $508,129 |
| Atorvastatin Calcium | Generic | 389 | 126 | $13,347 |
| Rosuvastatin Calcium | Generic | 253 | 91 | $18,219 |
| Amlodipine Besylate | Generic | 219 | 70 | $2,927 |
| Lisinopril | Generic | 218 | 73 | $2,573 |
| Furosemide | Generic | 217 | 76 | $2,080 |
| Metoprolol Tartrate | Generic | 176 | 59 | $2,516 |
| Isosorbide Mononitrate Er (Isosorbide Mononitrate) | Brand | 155 | 50 | $4,948 |
| Losartan Potassium | Generic | 125 | 46 | $3,152 |
Hospital affiliations
Frequently asked questions
What is Dr. Mark O'Connor's medical specialty?
Dr. Mark O'Connor practices Cardiovascular Disease Physician in Leominster, MA.
Where does Dr. Mark O'Connor practice?
Dr. Mark O'Connor practices at 100 Hospital RD, Leominster, MA 014532253. Office phone: 9784662052.
What is Dr. Mark O'Connor's NPI?
Dr. Mark O'Connor's National Provider Identifier (NPI) is 1215297270, issued by NPPES.
Does Dr. Mark O'Connor accept Medicare assignment?
Yes. Dr. Mark O'Connor accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mark O'Connor commonly perform?
Top Medicare-reported procedures in 2023: Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (HCPCS 93000); Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (HCPCS 93010); Established patient office or other outpatient visit (HCPCS 99214). Source: CMS Medicare Physician & Other Practitioners file.