Denisa L. Hagau, MD

Medicare activity in 2024

Official CMS public-use data for Denisa L. Hagau, 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. Ultrasound of heart with color-depicted blood flow, rate, direction and valve function (93306)636 services
2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)516 services
3. Ultrasound of heart with color-depicted blood flow, rate and valve function (93325)144 services
4. Ultrasound of heart blood flow, valves and chambers, follow-up (93321)138 services
5. Ultrasound of heart, follow-up (93308)133 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%
• Ischemic heart disease59%
• Heart failure59%
• Arthritis50%
• Atrial fibrillation46%

Hospitals where Denisa L. Hagau works

Medicare's Facility Affiliation Data lists Denisa L. Hagau 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.

• Hancock County Health SystemBritt, IA · Critical Access Hospital · Emergency services: listed by Medicare · CCN 161307
• Kossuth Regional Health CenterAlgona, IA · Critical Access Hospital · Medicare rating: 1 of 5 stars · Emergency services: listed by Medicare · CCN 161353
• MercyOne North Iowa Medical CenterMason City, IA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 160064
• Mitchell County Regional HealthOsage, IA · Critical Access Hospital · Medicare rating: 3 of 5 stars · Emergency services: not listed by Medicare · CCN 161323
• Palo Alto County HospitalEmmetsburg, IA · Critical Access Hospital · Emergency services: listed by Medicare · CCN 161357

Practice locations

Addresses where Denisa L. Hagau is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 14; the Medicare profile lists all.

• 1000 4th St SWMason City, IA 50401
• 1316 S Main St, Iowa Specialty HospitalClarion, IA 50525 (515) 532‑1281
• 1515 S Phillips StAlgona, IA 50511
• 1515 S Phillips St, Kossuth Regional Health CenterAlgona, IA 50511 (515) 295‑2451
• 1519 S Phillips StAlgona, IA 50511 (515) 295‑7714

Group practices

Medicare enrollment lists Denisa L. Hagau as a member of these groups (CMS data updated October 2, 2026).

• North Iowa Mercy Clinics302 clinicians in the group
• Kossuth Regional Health Center25 clinicians in the group
• Palo Alto County Hospital23 clinicians in the group

Specialties

• Cardiovascular Disease (Cardiology)primary

Find other Cardiovascular Disease (Cardiology) doctors in Iowa →

Other cardiologists in Mason City

Clinicians with the same Medicare primary specialty in Mason City, IA — not a recommendation.

• Robert Ruelaz, MD
• Kumar M. Bobba, MD
• Radu Hagau, MD
• Michael J. Sarik, DO
• Amad Zineldine, MD
• Bryan M. Spalding, MD
• Richard R. Rattin, DO
• Youssef Nasr, MD

All cardiologists in Mason City →

Other clinicians in North Iowa Mercy Clinics

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

• Taylor P. Julius
• Flavio W. Kruter, MD
• Siddharth A. Verma, DO
• Michael T. Spooner, MD
• Lisa Holt
• Corey J. Thompson, 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