Medicare Enrolled

Dr. Mariana Chavez Mac Gregor, M.D., M.S.C.

Internal Medicine · Houston, TX
Practice pattern: Clinical Cardiology— Primarily office-based clinical cardiology
Consulting-driven
1515 HOLCOMBE BLVD, Houston, TX 77030
7137926161
In practice since 2007 (18 years)
NPI: 1740408624 verify on NPPES ↗
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. Chavez Mac Gregor 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 →
Are you Dr. Chavez Mac Gregor? Request a correction or review of any data shown here. Provider portal →

What this data tells you about Dr. Chavez Mac Gregor

Dr. Mariana Chavez Mac Gregor is an internal medicine in Houston, TX, with 18 years in practice. Based on federal Medicare data, Dr. Chavez Mac Gregor performed 160 Medicare services across 79 unique beneficiaries.

Between the years covered by Open Payments, Dr. Chavez Mac Gregor received a total of $158,585 from 16 pharmaceutical and/or device companies across 127 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in internal medicine. The majority of payments are for consulting, which typically reflects recognized clinical expertise sought by manufacturers. Patients may wish to discuss these relationships with their provider.

The Data Coverage level for Dr. Chavez Mac Gregor is Very High — reflecting how much public federal data is available about this provider. This is not a quality rating. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.

✓ 18 years in practice▲ 160 Medicare services$ $158,585 industry payments

Medicare Practice Summary

Medicare Utilization ↗
160
Medicare services
Bottom 16% in TX for internal medicine
Lower Medicare volume may reflect subspecialty focus, hospital-based work, or a higher share of non-Medicare patients.
79
Unique beneficiaries
$93
Avg. Medicare payment
Medicare patients only (65+ / disabled) · Not a quality rating · How to read this →
~9 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.

ProcedureVolumeAvg. paidAvg. submitted
Office visit, established patient, complex (40-54 min)85$109$534
Office visit, established patient (30-39 min)64$69$265
New patient office visit, complex (60-74 min)11$115$615
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.

Industry Payment Transparency

Open Payments through 2024 ↗
$158,585
Total received (2018-2024)
Avg $22,655/year across 7 years
Top 1% in TX for internal medicine
16
Companies
127
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.

Consulting
Expert advisory fees, typically reflecting recognized clinical expertise
$103,736 (65.4%)
Speaking / Promotional
Speaker programs, honoraria, and industry-sponsored educational events
$45,082 (28.4%)
Meals & Travel
Food, beverages, travel, and lodging — typically low-value
$9,768 (6.2%)

Payment trend by year

Annual totals from pharmaceutical and medical device companies.

2024
$22,332
2023
$48,122
2022
$24,817
2021
$24,095
2020
$19,135
2019
$16,712
2018
$3,373

Payments by company (2024)

Consulting
Speaking
Meals & Travel
Research
Merck Sharp & Dohme LLC
$24,689
AstraZeneca UK Limited
$24,347
PFIZER INC.
$21,982
AstraZeneca AB
$15,300
Genentech, Inc.
$14,567
Dr.Reddy's Laboratories,Inc.
$10,950
F. Hoffmann-La Roche AG
$10,118
PFIZER INTERNATIONAL LLC
$8,602
AstraZeneca Pharmaceuticals LP
$7,565
Eli Lilly and Company
$6,400
Daiichi Sankyo Inc.
$3,708
Novartis Pharmaceuticals Corporation
$2,932
Daiichi Sankyo Company LTD
$2,740
PFIZER S.A.
$2,200
Roche Products Limited
$1,320
Eisai Co., Ltd.
$1,166
Top 3 companies account for 44.8% of total payments
Associated products mentioned in payments ›
Enhertu · Fulvestrant · IBRANCE · INLYTA · KISQALI · LORBRENA · Lenvima · Non-Covered Product · SUTENT · TALZENNA · Truqap
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 →

The majority of payments (65%) are consulting fees, which typically reflect recognized clinical expertise sought by manufacturers. Total industry engagement is in the top 1% for internal medicine in TX.

Equivalent to $99,116 per 100 Medicare services performed
Looking for a internal medicine in Houston?
Compare internal medicines in the Houston area by procedure volume, costs, and industry payment transparency.
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Geographic Context

Internal Medicines within 10 mi
2,667
Per 100K population
56.0
County median income
$73,104
Nearest hospital
MEMORIAL HERMANN - TEXAS MEDICAL CENTER
0.0 mi

Data Sources

Provider Registry✓ NPPESWeekly updates
Medicare Enrollment✓ PECOSMonthly updates
Practice Data✓ Medicare Util.Annual (CY lag)
Industry Payments✓ Open PaymentsCY 2024
Disciplinary History— Not publicN/A

This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This measures how much public data is available about a provider — not how good they are. How we calculate this →

Summary

Dr. Chavez Mac Gregor is a clinical cardiology specialist, with moderate Medicare volume, and high industry engagement (consulting-driven, top 1%), with 18 years of practice experience.

This summary is auto-generated from federal data. It describes data availability and patterns — not clinical quality. Read our methodology →

Frequently Asked Questions

Is Dr. Chavez Mac Gregor experienced with office visit, established patient, complex (40-54 min)?
Based on Medicare claims data, Dr. Chavez Mac Gregor performed 85 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. Chavez Mac Gregor receive payments from pharmaceutical companies?
Yes. Dr. Chavez Mac Gregor received a total of $158,585 from 16 companies across 127 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. Chavez Mac Gregor's costs compare to other internal medicines in Houston?
Dr. Chavez Mac Gregor's average Medicare payment per service is $93. 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. Chavez Mac Gregor) 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. The Transparency Score measures 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.

Provider corrections: Provider portal · Privacy questions: Privacy Policy · Terms: Terms of Use · Methodology: Methodology

Data Disclaimer — Data sourced from the Centers for Medicare & Medicaid Services (CMS): National Plan and Provider Enumeration System (NPPES), Open Payments program, Medicare Provider Utilization and Payment Data, and Provider Enrollment & Certification data (PECOS). Published under the Freedom of Information Act (FOIA). This website is not affiliated with, endorsed by, or authorized by CMS, HHS, or the U.S. Government. Data may contain errors as reported to CMS by providers and reporting entities. Payments from industry are legal and do not indicate wrongdoing. Medicare data reflects only patients aged 65+ or those with qualifying disabilities. For corrections, contact CMS directly. This information does not constitute medical advice and should not be used as the sole basis for choosing a healthcare provider. Procedure descriptions use plain language and do not reference CPT® codes, which are copyrighted by the American Medical Association. Full methodology → · Report a data error → · Privacy policy →