Medicare Enrolled
Dr. Justin Mao, MD
Internal Medicine · Downers Grove, IL
Practice pattern: Electrophysiology & Remote
— Practice combining electrophysiology and remote services
Low-engagement
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Mao from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
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What this data tells you about Dr. Mao
Dr. Justin Mao is an internal medicine specialist in Downers Grove, IL, with 21 years of NPI registration. Based on federal Medicare data, Dr. Mao performed 2,765 Medicare services across 2,276 unique beneficiaries.
Between the years covered by Open Payments, Dr. Mao received a total of $7,735 from 27 pharmaceutical and/or device companies across 168 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in internal medicine. Most payments are for meals and travel — low-value interactions common across virtually all practicing physicians. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Mao is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
✓ 21 years in practice
▲ Top 10% volume in IL
$7,735 industry payments
Medicare Practice Summary
Medicare Utilization ↗2,765
Medicare services
Top 10% in IL for internal medicine
2,276
Unique beneficiaries
$82
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
~132 Medicare services per year of practice
Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Office visit, established patient, complex (40-54 min) An office or outpatient visit for an existing patient lasting between 40 and 54 minutes. This level of service is determined by the total time spent on the date of the encounter. |
502 | $127 | $366 |
| Electrocardiogram (EKG), 12-lead A standard heart rhythm test using at least 12 leads to record electrical activity. A healthcare provider interprets the results and provides a written report. |
394 | $11 | $82 |
| Remote pacemaker monitoring, 90 days Remote assessment of a pacemaker system, including single, dual, multiple lead, or leadless devices, performed up to 90 days apart. |
352 | $23 | $197 |
| Pacemaker programming, dual lead system Adjustment and configuration of a dual-lead pacemaker device to ensure proper operation and settings. |
165 | $61 | $196 |
| Remote evaluation of implantable defibrillator system Remote assessment of a single, dual, or multiple lead implantable defibrillator system within 90 days of the previous evaluation. |
146 | $27 | $309 |
| Hospital follow-up visit, high complexity Subsequent hospital inpatient or observation care for an existing patient involving high-level medical decision making, with at least 50 minutes total time on the date of the encounter. |
145 | $93 | $248 |
| Initial hospital admission, high complexity Initial hospital inpatient or observation care for a new patient involving high-level medical decision making, with at least 75 minutes total time on the date of the encounter. |
127 | $140 | $437 |
| New patient office visit, complex (60-74 min) | 121 | $175 | $465 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
75 | $72 | $178 |
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
68 | $104 | $259 |
| Sedation by physician, initial 15 minutes Administration of a drug to induce depression of consciousness by the physician performing a procedure. This code covers the initial 15 minutes of sedation for patients aged 5 years or older. |
67 | $10 | $163 |
| Remote cardiac rhythm monitor evaluation, up to 30 days Review and analysis of data from a remote cardiac rhythm monitoring system over a period of up to 30 days. |
59 | $21 | $156 |
| Programming of multiple lead implantable defibrillator system Adjustment and testing of the settings for an implanted heart device with multiple leads to ensure proper function. |
51 | $76 | $303 |
| External shock to heart to regulate heart beat A procedure that delivers an electric shock to the heart from outside the body to restore a normal heart rhythm. |
45 | $86 | $766 |
| 2-day continuous ECG with professional review A two-day continuous electrocardiogram recording that includes a review by a healthcare professional. |
39 | $13 | $147 |
| Echocardiogram, transthoracic An ultrasound of the heart that uses color to show blood flow, rate, direction, and valve function. |
36 | $55 | $256 |
| Hospital follow-up visit, moderate complexity Follow-up hospital visit for an existing patient involving moderate medical decision making. The visit requires at least 35 minutes of time spent on the date of service. |
33 | $58 | $168 |
| Continuous ECG monitoring with transmission and review Continuous electrocardiogram monitoring for up to 30 days with symptom tracking. The data is transmitted and reviewed by a healthcare professional who provides a report. |
29 | $19 | $91 |
| Pacemaker programming, single lead Adjustment and testing of a single-lead pacemaker to ensure it functions correctly. |
28 | $52 | $167 |
| Pacemaker system programming Adjustment and testing of a multi-lead pacemaker to ensure proper function and settings. |
28 | $71 | $228 |
| Programming of dual lead implantable defibrillator system Adjustment and testing of the settings for an implanted heart device with two leads to ensure proper function. |
26 | $74 | $274 |
| Evaluation of implantable heart and blood vessel monitoring system This procedure involves checking the function and data of an implanted device used to monitor heart and blood vessel activity. |
25 | $35 | $117 |
| Blood draw (venipuncture) Insertion of a needle into a vein to collect a blood sample. |
24 | $8 | $22 |
| Atrial fibrillation ablation with pulmonary vein isolation A procedure to treat atrial fibrillation by mapping the heart's electrical activity and destroying tissue causing irregular contractions. This is done by isolating the pulmonary veins using catheter-based destruction. |
24 | $808 | $4,307 |
| Catheter ablation for abnormal heart rhythm A procedure where catheters are inserted to destroy tissue causing irregular heartbeats. |
23 | $262 | $1,615 |
| Pacemaker insertion with heart chamber electrodes A surgical procedure to implant a pacemaker device and place electrodes into the upper and lower chambers of the heart to regulate heart rhythm. |
21 | $443 | $2,687 |
| Cardiac rhythm monitor evaluation Review and analysis of data recorded by a cardiac rhythm monitoring device to assess heart activity. |
20 | $39 | $124 |
| External EKG monitoring, 8-15 days Continuous external electrocardiogram recording and review over a period of 8 to 15 days to monitor heart rhythm. |
19 | $21 | $54 |
| Programming of single lead implantable defibrillator system Adjustment and testing of the settings for a single-lead implantable cardioverter-defibrillator (ICD) to ensure proper function. |
19 | $59 | $215 |
| Continuous EKG monitoring review, 48-7 days Review and interpretation of continuous external EKG recordings lasting more than 48 hours up to 7 days. |
17 | $19 | $51 |
| Removal and replacement of dual lead permanent pacemaker This procedure involves removing an existing permanent pacemaker with two leads and replacing it with a new device. It is performed to update or repair the heart rhythm management system. |
15 | $302 | $1,357 |
| Insertion of implantable heart rhythm monitor A small device is placed under the skin to continuously record the heart's electrical activity. This helps detect irregular heart rhythms that may not appear during a standard office visit. |
11 | $72 | $10,874 |
| Radiofrequency ablation for supraventricular tachycardia A procedure to locate and destroy abnormal heart tissue in the upper chambers of the heart that causes a rapid heart rate. |
11 | $715 | $3,229 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. A higher procedure volume generally indicates more experience with that procedure.
34.2% high complexity
0.0% medium
65.8% routine
Industry Payment Transparency
Open Payments through 2024 ↗$7,735
Total received (2018-2024)
Avg $1,105/year across 7 years
Top 9% in IL for internal medicine
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
27
Companies
168
Individual payments
All payments are legal and publicly reported · Not evidence of wrongdoing · How to interpret →
Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Meals & Travel
Food, beverages, travel, and lodging — typically low-value
$4,271 (55.2%)
Speaking / Promotional
Speaker programs, honoraria, and industry-sponsored educational events
$3,464 (44.8%)
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2024
$511
2023
$4,021
2022
$643
2021
$441
2020
$180
2019
$837
2018
$1,101
Payments by company (2024)
Consulting
Speaking
Meals & Travel
Research
Abbott Laboratories
$248
Boston Scientific Corporation
$132
ABIOMED
$38
Actelion Pharmaceuticals US, Inc.
$34
Edwards Lifesciences Corporation
$34
PFIZER INC.
$24
Top 3 companies account for 82.0% of 2024 payments
All-time payments by company (2018-2024) ›
Impulse Dynamics (USA) Inc.
$3,464
Abbott Laboratories
$1,266
Medtronic Vascular, Inc.
$446
PFIZER INC.
$368
Boston Scientific Corporation
$328
Amgen Inc.
$211
AtriCure, Inc.
$180
E.R. Squibb & Sons, L.L.C.
$164
CVRx, Inc.
$163
SANOFI-AVENTIS U.S. LLC
$138
Janssen Pharmaceuticals, Inc
$118
BIOTRONIK INC.
$116
ZOLL Respicardia, Inc.
$115
Penumbra, Inc.
$104
Philips Electronics North America Corporation
$78
Novartis Pharmaceuticals Corporation
$70
Boehringer Ingelheim Pharmaceuticals, Inc.
$65
ABIOMED
$55
Lundbeck LLC
$54
BOSTON SCIENTIFIC CORPORATION
$48
Regeneron Healthcare Solutions, Inc.
$37
Actelion Pharmaceuticals US, Inc.
$34
Edwards Lifesciences Corporation
$34
Medtronic, Inc.
$32
Baylis Medical Company Inc
$25
AstraZeneca Pharmaceuticals LP
$11
Aziyo Biologics, Inc.
$10
Top 3 companies account for 66.9% of all-time payments
Associated products mentioned in payments ›
(4066) Tack Endo Sys ATK · (6571) Eagle Eye · (8874) inCourage · AMPLATZER · AMPLATZER AMULET · BRILINTA · Barostim Neo System · CARDIOMEMS · CHANTIX · Claria MRI · Corlanor · ECM · ELIQUIS · ENSITE · ENSITE PRECISION · ENTRESTO · EP-WorkMate Claris System · EPI-SENSE GUIDED COAGULATION SYSTEM WITH VISITRAX · EnSite Precision Cardiac Mapping System · Impella · JARDIANCE · LATITUDE Communicator Power Supply · LUX DX · MULTAQ · Micra · NA · NORTHERA · OPTIMIZER · PERCLOSE PROSTYLE · PRADAXA · PRALUENT · PRALUENT ALIROCUMAB INJECTION · RESOLUTE ONYX · RESONATE · RHYTHMIA · ROTAPRO · Repatha · Reveal LINQ · SENSOR ENABLED · SYNERGY · SelectSecure · Smart Coil · TACTICATH ABLATION CATHETER · UPTRAVI · VYNDAQEL · VersaCross Access Solution · ViewMate Intracardiac Echo · WATCHMAN · WATCHMAN Access System · WATCHMAN FLX · WORKMATE CLARIS · XARELTO · Xience Sierra Coronary Stent System · remede System
Should you be concerned? Payments from pharmaceutical and device companies are legal and common — 57% of U.S. physicians receive at least one. They often reflect legitimate consulting, research, or education. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
Most payments (55%) are for meals and travel — low-value interactions that are common across virtually all practicing physicians. Total industry engagement is in the top 9% for internal medicine in IL.
Geographic Context
Internal medicine physicians within 10 mi
6,188
Per 100K population
667.3
County median income
$110,502
Nearest hospital
ADVOCATE GOOD SAMARITAN HOSPITAL
0.0 mi
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Mao is an electrophysiology & remote specialist, with above-average Medicare volume (top 10% in IL), with low-engagement industry engagement in the top 9% of IL peers, with 21 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Mao experienced with office visit, established patient, complex (40-54 min)?
Based on Medicare claims data, Dr. Mao performed 502 office visit, established patient, complex (40-54 min) services. Research suggests that higher procedure volume is often associated with better outcomes, particularly for complex procedures. Note that Medicare data only captures patients aged 65 and older, so the total practice volume across all patients is likely higher.
Does Dr. Mao receive payments from pharmaceutical companies?
Yes. Dr. Mao received a total of $7,735 from 27 companies across 168 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common among physicians — 57% of all U.S. physicians receive at least one industry payment. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Mao's costs compare to other internal medicine physicians in Downers Grove?
Dr. Mao's average Medicare payment per service is $82. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Mao) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating a long track record of practice, Medicare participation, and industry disclosure. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Each data source has its own update cycle. Provider registry data (NPPES) is updated weekly. Medicare enrollment (PECOS) is updated monthly. Medicare practice data has a ~2 year lag — the most recent available is typically 2 years prior. Industry payment data (Open Payments) is published annually, usually in June, covering the prior calendar year. We display the data date prominently on each section so you always know how current it is. See our data freshness policy →
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About this page
All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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