Zainab Mahmoud, MD

Medicare activity in 2024

Official CMS public-use data for Zainab Mahmoud, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Most frequent services

1. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)46 services
2. Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes (99222)24 services
3. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)17 services
4. Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)13 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

• High blood pressure75%
• High cholesterol75%
• Heart failure65%
• Ischemic heart disease59%
• Atrial fibrillation53%
• Arthritis44%

Hospitals where Zainab Mahmoud works

Medicare's Facility Affiliation Data lists Zainab Mahmoud at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

• Barnes Jewish HospitalSaint Louis, MO · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 260032
• Memorial HospitalBelleville, IL · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 140185

Practice locations

Addresses where Zainab Mahmoud is enrolled with Medicare (CMS data updated October 2, 2026).

• 1 Barnes Jew Hosp PlzSaint Louis, MO 63110 (314) 747‑3000
• 4921 Parkview PlSaint Louis, MO 63110

Group practices

Medicare enrollment lists Zainab Mahmoud as a member of this group (CMS data updated October 2, 2026).

• Washington University3,029 clinicians in the group

Specialties

• Cardiovascular Disease (Cardiology)primary
• Internal Medicinealso

Find other Cardiovascular Disease (Cardiology) doctors in Missouri →

Other cardiologists in Saint Louis

Clinicians with the same Medicare primary specialty in Saint Louis, MO — not a recommendation.

• Robert L. Petersen, MD
• Majesh Makan, MD
• Richard Keating, MD
• Mary C. Gamache, MD
• Douglas L. Mann, MD
• Crystal N. Azu, MD
• Sandor J. Kovacs, MD
• Anubha Agarwal, MD

All cardiologists in Saint Louis →

Other clinicians in Washington University

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Arakua Welbeck, MD
• Caitlin A. Palmer, CNA
• Michelle D. Rudman
• Martin N. Reis, MD
• Chi Tsai Tang, MD
• Julie Margenthaler, MD

Clinician information

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians