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DR. SARAH MICHELLE LEE STACK MD
NPI 1437473097
Pediatrics - Pediatric Cardiology in Walnut Creek, CA

Active since March 25, 2010PECOS EnrolledAccepts Medicare Assignment
106 LA CASA VIA STE 220, WALNUT CREEK, CA 94598(650) 497-8000 Get Directions Write a Review

NPPES record last updated: April 6, 2021. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Apr 6, 2021, Sep 3, 2019, Aug 30, 2016 (3 updates tracked since 2016).

About Dr. Sarah Michelle Lee Stack Md NPPES

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

DR. SARAH MICHELLE LEE STACK MD (NPI 1437473097) is an individual pediatric cardiology provider in Walnut Creek, California, licensed in California (A162678) and active in the NPI registry since March 2010. She is enrolled in Medicare PECOS and is a graduate of Other (2010).

NPPES Registry Identity

NPI1437473097
Entity TypeIndividualFemale
Primary Taxonomy2080P0202X
Provider Legal NameDR. SARAH MICHELLE LEE STACKCredential: MD
Location Address106 LA CASA VIA STE 220Walnut Creek, CA 94598-3012
Mailing Address106 La Casa Via Ste 220Walnut Creek, CA 94598-3012 · (650) 497-8000
Phone(650) 497-8000
Sole ProprietorNo
Medical School CMSOtherGraduated 2010
Enumeration DateMarch 25, 2010
Last NPPES UpdateApril 6, 20213 updates tracked since enumeration
NPPES CertifiedApril 6, 2021
✔ NPI 1437473097 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPediatrics · Pediatric CardiologyAllopathic & Osteopathic Physicians
Taxonomy Code2080P0202X
Licenses✔ Licensed in CA · A162678✔ Licensed in WA · MD60652463
Definition
A pediatric cardiologist provides comprehensive care to patients with cardiovascular problems. This specialist is skilled in selecting, performing and evaluating the structural and functional assessment of the heart and blood vessels, and the clinical evaluation of cardiovascular disease.
106 LA CASA VIA STE 220, Walnut Creek, CA 94598
Open in Google Maps ↗

Other Names 1

Other Name (5)Sarah Ml Keefer

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

Dr. Sarah Michelle Lee Stack 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 ID3971746744
PECOS Enrollment IDI20190715000902
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 Reassignment

Medicare enrollment records show Sarah Stack reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Lpch Medical Group Div Of Lucile
34 mi
Children
725 WELCH RD
Palo Alto, CA 94304
  • Reassigned Medicare billing, California enrollment
  • 3,617 clinicians in this Medicare group
NPI 1417907940 (650) 498-6762

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

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Sarah Stack's NPI number?

The NPI number for Sarah Stack is 1437473097. It was assigned to this individual provider in the NPPES registry on March 25, 2010. The provider is also known as Sarah Ml Keefer.

Where is Sarah Stack located?

Sarah Stack practices at 106 La Casa Via Ste 220, Walnut Creek, CA 94598. The listed phone number is (650) 497-8000.

What is Sarah Stack's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Cardiology, with taxonomy code 2080P0202X.

Is Sarah Stack enrolled in Medicare?

Yes. Sarah Stack is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Sarah Stack's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Sarah Stack reassigns Medicare benefits to Lpch Medical Group Div Of Lucile (Palo Alto, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Sarah Stack's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Sarah Stack was last updated on April 6, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years 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.