WILLIAM JOSEPH STEPHAN MD
NPI 1851344931
Internal Medicine - Interventional Cardiology in Naperville, IL

Q: What is William Stephan's NPI number?

The NPI number for William Stephan is 1851344931. It was assigned to this individual provider in the NPPES registry on May 18, 2006.

Q: What is William Stephan's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Interventional Cardiology, with taxonomy code 207RI0011X.

Q: When was this NPI record last updated?

The NPPES record for William Stephan was last updated on April 24, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 17 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since May 18, 2006PECOS EnrolledAccepts Medicare Assignment

10 MARTIN AVE STE 200, NAPERVILLE, IL 60540(630) 600-0700(630) 600-0701 Get Directions Write a Review

NPPES record last updated: April 24, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

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About William Joseph Stephan Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WILLIAM JOSEPH STEPHAN MD (NPI 1851344931) is an individual interventional cardiology provider in Naperville, Illinois, licensed in Illinois (036.090607) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS, is affiliated with Elmhurst Memorial Hospital, and is a graduate of Tufts University School Of Medicine (1987).

NPPES Registry Identity

NPI1851344931

Entity TypeIndividualMale

Primary Taxonomy207RI0011X

Provider Legal NameWILLIAM JOSEPH STEPHANCredential: MD

Location Address10 MARTIN AVE STE 200Naperville, IL 60540-6535

Mailing Address10 Martin Ave Ste 200Naperville, IL 60540-6535 · (630) 600-0700 · Fax (630) 600-0701

Phone(630) 600-0700

Fax(630) 600-0701

Sole ProprietorNo

Medical School CMSTufts University School Of MedicineGraduated 1987

Enumeration DateMay 18, 2006

Last NPPES UpdateApril 24, 2025

NPPES CertifiedApril 24, 2025

✔ NPI 1851344931 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Interventional CardiologyAllopathic & Osteopathic Physicians

Taxonomy Code207RI0011X

Licenses✔ Licensed in IL · 036.090607✔ Licensed in IL · 036090607

Definition

An area of medicine within the subspecialty of cardiology, which uses specialized imaging and other diagnostic techniques to evaluate blood flow and pressure in the coronary arteries and chambers of the heart and uses technical procedures and medications to treat abnormalities that impair the function of the cardiovascular system.

Also ListedInternal Medicine · Cardiovascular DiseaseTaxonomy 207RC0000X · License 036.090607 (IL)

10 MARTIN AVE STE 200, Naperville, IL 60540

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

William Joseph Stephan Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID8527970250

PECOS Enrollment IDI20040601000300

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show William Stephan reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Cardiovascular Institute Gpe Inc

Same address

Cardiovascular Disease

10 MARTIN AVE STE 200
Naperville, IL 60540

Reassigned Medicare billing, Illinois enrollment
61 clinicians in this Medicare group

NPI 1992594022 (630) 600-0700

Edward Hospital

0.1 mi

General Acute Care Hospital

801 S WASHINGTON ST
Naperville, IL 60540

Reassigned Medicare billing, Illinois enrollment
268 clinicians in this Medicare group

NPI 1013969013 (630) 655-0450

Advocate Health And Hospitals Corporation

8.2 mi

Cardiovascular Disease

3825 HIGHLAND AVE, TOWER 2 SUITE 400
Downers Grove, IL 60515

Reassigned Medicare billing, Illinois enrollment
4,870 clinicians in this Medicare group

NPI 1285903849 (630) 719-4799

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 28

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Rubidium rb-82, diagnostic, per study dose, up to 60 millicuries A9555

Rubidium Rb-82 is a radioactive drug used in a PET scan to help visualize the heart. It helps detect areas with poor blood flow, aiding in diagnosing heart conditions. The dose is up to 60 millicuries per study.

935 services477 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

828 services575 patients

Exercise or drug-induced heart stress test with electrocardiogram (ecg) with review by physician 93018

An exercise or drug-induced heart stress test with ECG is a procedure to assess how your heart functions under stress. It can involve exercising or medication to make your heart work harder while an ECG records its activity. A physician reviews the results.

681 services675 patients

Nuclear medicine studies of blood flow in heart muscle at rest and with stress with concurrent ct scan 78431

This is a diagnostic test where a tiny amount of radioactive material is used to examine your heart's blood flow at rest & during stress, alongside a CT scan for detailed images. It helps identify any heart-related issues like blockages or damage.

483 services477 patients

Technetium tc-99m sestamibi, diagnostic, per study dose A9500

Technetium Tc-99m Sestamibi is a diagnostic test used to create images of your heart or breast tissues. It involves a safe radioactive substance injection that helps doctors to detect any abnormalities or changes in these tissues.

282 services141 patients

Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000

An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.

206 services186 patients

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

200 services181 patients

Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306

This is a heart ultrasound, also known as an echocardiogram. It uses sound waves to create pictures of your heart, showing how blood flows through it. The color depicts the blood flow's speed and direction. It also checks the heart's valves to ensure they're working properly.

197 services190 patients

Nuclear medicine studies of heart muscle at rest and with stress and spect 78452

Nuclear medicine studies of the heart involve two parts: rest and stress. During rest, images are taken of your heart at ease. During stress, images are taken after exercise or medication-induced stress. SPECT is a special imaging technique providing 3D pictures of your heart, helping identify any issues.

184 services183 patients

Exercise or drug-induced heart stress test with electrocardiogram (ecg) with review by physician 93018

163 services163 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233

Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.

160 services96 patients

Nuclear medicine studies of heart muscle at rest and with stress and spect 78452

154 services154 patients

Injection, sulfur hexafluoride lipid microspheres, per ml Q9950

This procedure involves an injection of sulfur hexafluoride lipid microspheres. These tiny bubbles enhance the quality of ultrasound images, aiding in more accurate diagnoses. The injection is safe and typically used in cardiovascular imaging.

145 services27 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

80 services57 patients

Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306

76 services76 patients

Use of a drug to induce depression of consciousness by physician performing a procedure (5 years or older), initial 15 minutes 99152

This procedure involves a doctor administering a medication to reduce your consciousness during a procedure. This helps in managing discomfort and anxiety. The initial application lasts for 15 minutes and is for individuals aged 5 years or older.

55 services51 patients

Injection, regadenoson, 0.1 mg J2785

Regadenoson injection, 0.1 mg, is a medication used to help visualize the heart during a stress test. It works by increasing blood flow in the arteries of the heart. It's injected into a vein and is generally well-tolerated.

53 services14 patients

New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203

This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.

48 services48 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

48 services48 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

46 services43 patients

Insertion of tube in left lower heart chamber and coronary artery for diagnosis with review by radiologist 93458

This procedure involves placing a tube into your left lower heart chamber and coronary artery. It helps doctors diagnose heart conditions by allowing them to view these areas in detail. A radiologist will review the images to ensure accurate diagnosis.

24 services23 patients

Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223

Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.

21 services21 patients

Replacement of aortic valve through the skin and femoral artery 33361

This procedure, known as Transcatheter Aortic Valve Replacement (TAVR), involves replacing a damaged aortic valve through a small incision in the leg. A catheter is inserted into the femoral artery and guided up to the heart. The new valve is then positioned and deployed, restoring normal blood flow.

19 services19 patients

Electrocardiogram (ecg) up to 30 days continuous with transmission of patient triggered events with review and report by health care professional 93229

An Electrocardiogram (ECG) is a test that records your heart's electrical activity for up to 30 days. You trigger a transmission if you feel symptoms, which is then reviewed by a healthcare professional. The report helps diagnose heart conditions.

15 services15 patients

Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231

Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.

14 services13 patients

Hospital discharge day management, 30 minutes or less 99238

Hospital discharge day management of 30 minutes or less includes finalizing your treatment, discussing your progress, and planning after-care at home. It ensures you're ready to leave the hospital and continue recovery safely.

14 services14 patients

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215

This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.

13 services13 patients

Ultrasound of heart, follow-up 93308

A follow-up ultrasound of the heart, also known as an echocardiogram, is a non-invasive test that uses sound waves to create images of your heart. It helps doctors monitor your heart's function and structures after initial assessment or treatment.

11 services11 patients

Hospital Affiliations CMS Care Compare 4

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Elmhurst Memorial Hospital

Acute Care Hospitals · Elmhurst, IL

4/5 CMS rating

OwnershipProprietary

CMS Certification Number140200

Location155 East Brush Hill RoadElmhurst, IL 60126 · Du Page County

Emergency services Birthing friendly

Northwestern Medicine Delnor Community Hospital

Acute Care Hospitals · Geneva, IL

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140211

Location300 Randall RdGeneva, IL 60134 · Kane County

Emergency services Birthing friendly

Edward Hospital

Acute Care Hospitals · Naperville, IL

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140231

Location801 South WashingtonNaperville, IL 60540 · Du Page County

Emergency services Birthing friendly

Northwestern Medicine Central Dupage Hospital

Acute Care Hospitals · Winfield, IL

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140242

Location25 North Winfield RoadWinfield, IL 60190 · Du Page County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60540 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$137.43 typical visit price

range $59.81 – $181.38

Typical copayment $34.35 (range $14.95 – $45.34)

Most-billed visit code 99204

Established Patient

$105.07 typical visit price

range $19.15 – $147.12

Typical copayment $26.26 (range $4.78 – $36.78)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

EHAB GHASSAN DABABNEH MD

Internal Medicine (Interventional Cardiology)