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Data Sources: Centers for Medicare & Medicaid Services (CMS), Medicare Provider Utilization and Payment Data
Disclaimer: This site is an independent journalism project. Data analysis and editorial content are not affiliated with or endorsed by CMS or any government agency. All spending figures are based on publicly available Medicare payment records.
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Methodology•Download Data
  1. Home
  2. Providers
  3. Tuan Nguyen
❤️
MDIndividual

Tuan Nguyen, M.D.

NPI: 1669644951
Fountain Valley, CA
8 years of data
Cardiology
$5.5M
Total Payments
30.1K
Beneficiaries
59.2K
Services
2.79x
Markup Ratio

Peer Comparison

98th
percentile in specialty
This provider$5.5M
Specialty median$193.1K

📋 Key Findings

1Billed $5.5M over 8 years
22.79x markup ratio (above median)
398th percentile in Cardiology by payments
4Payments surged 579% in 2018
54 procedures with >3x markup
✓ No flags detected

🔎 Data Analysis

This provider's $5.5M in total Medicare payments ranks in the 98th percentile of Cardiology providers nationally.

Medicare payments to this provider grew 8932% from 2014 to 2023.

AI-generated analysis based on Medicare payment data.

Annual Medicare Payments

Annual Services Provided

Avg Payment per Service

Markup Ratio Over Time

📈

Notable: Payments increased 579% in 2018

Year-over-year payment surges can indicate changes in practice volume, new services, or billing pattern shifts.

Submitted Charges vs. Medicare Payments

Average per-service amounts submitted by the provider compared to what Medicare actually paid — the gap represents the markup.

YearAvg SubmittedAvg PaidMarkup RatioGap per ServiceTotal PaymentsServicesBeneficiaries
2014$319.29$102.723.11x$216.57$14.2K142126
2015$262.50$88.062.98x$174.44$39.7K461386
2018$303.41$102.712.95x$200.70$269.7K2.9K1.6K
2019$274.97$100.352.74x$174.62$867.2K9.3K4.7K
2020$273.24$101.782.68x$171.46$943.8K9.7K4.5K
2021$432.22$156.912.75x$275.31$1.2M12.2K5.8K
2022$400.47$137.892.90x$262.58$928.4K10.1K5.5K
2023$379.57$125.653.02x$253.92$1.3M14.5K7.6K

Top Procedures (20)

99291Critical care delivery critically ill or injured patient, first 30-74 minutes⚠ 3.3x markup
$1.2M
6.6K services$185.10/svc3.25x markup
99233Subsequent hospital inpatient care, typically 35 minutes per day
$1.0M
11.4K services$89.72/svc2.52x markup
99214Established patient office or other outpatient, visit typically 25 minutes
$676.0K
7.3K services$93.20/svc2.57x markup
93306Ultrasound examination of heart including color-depicted blood flow rate, direction, and valve function
$500.0K
5.6K services$89.28/svc2.78x markup
99232Subsequent hospital inpatient care, typically 25 minutes per day
$465.3K
7.3K services$63.41/svc2.49x markup
78452Nuclear medicine study of vessels of heart using drugs or exercise multiple studies
$329.8K
773 services$426.68/svc2.71x markup
99223Initial hospital inpatient care, typically 70 minutes per day
$271.0K
1.7K services$157.08/svc2.79x markup
99204New patient office or other outpatient visit, typically 45 minutes
$165.1K
1.3K services$123.41/svc2.94x markup
36482Chemical destruction of incompetent vein of arm or leg, accessed through the skin using imaging guidance⚠ 3.2x markup
$110.0K
68 services$1.6K/svc3.16x markup
99222Initial hospital inpatient care, typically 50 minutes per day
$103.8K
909 services$114.21/svc2.59x markup
93000Routine EKG using at least 12 leads including interpretation and report⚠ 3.4x markup
$76.8K
6.8K services$11.24/svc3.41x markup
99221Initial hospital inpatient care, typically 30 minutes per day
$76.3K
890 services$85.77/svc2.55x markup
93970Ultrasound scan of veins of both arms or legs including assessment of compression and functional maneuvers
$69.5K
1.1K services$65.73/svc2.74x markup
A9500Technetium tc-99m sestamibi, diagnostic, per study dose
$64.5K
775 services$83.22/svc1.46x markup
93015Exercise or drug-induced heart and blood vessel stress test with EKG monitoring, physician supervision, interpretation, and report
$50.1K
894 services$56.07/svc2.90x markup
92928Catheter insertion of stents in major coronary artery or branch, accessed through the skin
$46.8K
101 services$463.17/svc2.74x markup
93458Insertion of catheter in left heart for imaging of blood vessels or grafts and left lower heart⚠ 3.3x markup
$40.6K
192 services$211.61/svc3.32x markup
93460Insertion of catheter in right and left heart for imaging of blood vessels or grafts and left lower heart
$28.0K
100 services$280.19/svc2.97x markup
93971Ultrasound scan of veins of one arm or leg or limited including assessment of compression and functional maneuvers
$20.7K
263 services$78.83/svc2.58x markup
93880Ultrasound scanning of blood flow (outside the brain) on both sides of head and neck
$18.5K
471 services$39.23/svc2.66x markup
Show detailed table ▾
CodeDescriptionServicesPaymentsAvg/ServiceMarkup
99291Critical care delivery critically ill or injured patient, first 30-74 minutes6.6K$1.2M$185.103.25x
99233Subsequent hospital inpatient care, typically 35 minutes per day11.4K$1.0M$89.722.52x
99214Established patient office or other outpatient, visit typically 25 minutes7.3K$676.0K$93.202.57x
93306Ultrasound examination of heart including color-depicted blood flow rate, direction, and valve function5.6K$500.0K$89.282.78x
99232Subsequent hospital inpatient care, typically 25 minutes per day7.3K$465.3K$63.412.49x
78452Nuclear medicine study of vessels of heart using drugs or exercise multiple studies773$329.8K$426.682.71x
99223Initial hospital inpatient care, typically 70 minutes per day1.7K$271.0K$157.082.79x
99204New patient office or other outpatient visit, typically 45 minutes1.3K$165.1K$123.412.94x
36482Chemical destruction of incompetent vein of arm or leg, accessed through the skin using imaging guidance68$110.0K$1.6K3.16x
99222Initial hospital inpatient care, typically 50 minutes per day909$103.8K$114.212.59x
93000Routine EKG using at least 12 leads including interpretation and report6.8K$76.8K$11.243.41x
99221Initial hospital inpatient care, typically 30 minutes per day890$76.3K$85.772.55x
93970Ultrasound scan of veins of both arms or legs including assessment of compression and functional maneuvers1.1K$69.5K$65.732.74x
A9500Technetium tc-99m sestamibi, diagnostic, per study dose775$64.5K$83.221.46x
93015Exercise or drug-induced heart and blood vessel stress test with EKG monitoring, physician supervision, interpretation, and report894$50.1K$56.072.90x
92928Catheter insertion of stents in major coronary artery or branch, accessed through the skin101$46.8K$463.172.74x
93458Insertion of catheter in left heart for imaging of blood vessels or grafts and left lower heart192$40.6K$211.613.32x
93460Insertion of catheter in right and left heart for imaging of blood vessels or grafts and left lower heart100$28.0K$280.192.97x
93971Ultrasound scan of veins of one arm or leg or limited including assessment of compression and functional maneuvers263$20.7K$78.832.58x
93880Ultrasound scanning of blood flow (outside the brain) on both sides of head and neck471$18.5K$39.232.66x

Markup Analysis

Charge-to-Payment Ratio

2.79x

This provider submits charges 2.79 times higher than what Medicare actually pays.

What This Means

A markup ratio of 2.79x means for every $100 Medicare pays, this provider initially charges $279. This is higher than the national average.

Location

Fountain Valley, CA

Provider Verification

Always verify provider credentials and location before scheduling appointments. This data reflects Medicare payments and may not include all practice locations.

Similar Providers

Other Cardiology providers in CA for peer comparison.

Tuan Nguyen (you)
$5.5M
Leo Polosajian, M.D.
$52.5M
Athar Ansari, M.D.
$38.2M
Hanumandla Reddy, M.D
$38.1M
Mehran Khorsandi, M.D.,
$36.4M
Shashi Sharma, D.M.
$35.4M
Show detailed table ▾
ProviderLocationTotal PaymentsStatus
Leo Polosajian, M.D.Reseda, CA$52.5M✓ Clear
Athar Ansari, M.D.El Centro, CA$38.2M✓ Clear
Hanumandla Reddy, M.DHanford, CA$38.1M✓ Clear
Mehran Khorsandi, M.D.,Los Angeles, CA$36.4M✓ Clear
Shashi Sharma, D.M.Visalia, CA$35.4M✓ Clear

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Data Sources

  • • Centers for Medicare & Medicaid Services (CMS)
  • • Medicare Provider Utilization and Payment Data (2014-2023)
  • • National Plan and Provider Enumeration System (NPPES)

Last Updated: February 2026 (data through 2023, the latest CMS release)

Note: All data is from publicly available Medicare records. OpenMedicare is an independent journalism project not affiliated with CMS.

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