Left-sided heart failure

Request an Appointment

Stages

During or after testing for heart failure, your healthcare professional may tell you the stage of disease. Staging helps determine the treatment. There are two main ways to determine the stage or class of heart failure:

New York Heart Association classification

The New York Heart Association (NYHA) classification system groups heart failure into four categories by number. You may see Roman numerals used for these categories.

  • Class 1 heart failure. There are no heart failure symptoms during daily activities or low-intensity exercise.
  • Class 2 heart failure. Everyday activities can be done without difficulty. But exertion causes shortness of breath or tiredness.
  • Class 3 heart failure. It's hard to complete everyday activities.
  • Class 4 heart failure. Shortness of breath happens even at rest. This category includes the most serious heart failure.

American College of Cardiology/American Heart Association classification

This stage-based classification system uses letters A to D. It includes a category for people who are at risk of developing heart failure.

  • Stage A. There are risk factors for heart failure but no signs or symptoms.
  • Stage B. There is heart disease but no signs or symptoms of heart failure.
  • Stage C. There is heart disease and current or previous signs or symptoms of heart failure.
  • Stage D. This is advanced heart failure that needs specialized treatments.

Healthcare professionals often use the classification systems together to help decide the right treatment options. Your health professional can help you understand your stage.

Request an appointment
Diagnosis & treatmentDoctors & departments
Sept. 17, 2026
  1. Colucci WS, et al. Heart failure: Clinical manifestations and diagnosis in adults. https://www.uptodate.com/contents/search. Accessed Sept. 1, 2026.
  2. Heart failure explained: Understanding symptoms, causes, diagnosis and treatment. American Heart Association. https://www.heart.org/en/health-topics/heart-failure/heart-failure-explained. Accessed Sept. 1, 2026.
  3. Types of heart failure. American Heart Association. https://www.heart.org/en/health-topics/heart-failure/types-of-heart-failure. Accessed Sept. 1, 2026.
  4. Ferri FF. Heart failure. In: Ferri's Clinical Advisor 2026. Elsevier; 2026. https://www.clinicalkey.com. Accessed Sept. 7, 2026.
  5. Heidenreich PA, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure. Circulation. 2022; doi:10.1161/CIR.0000000000001063.
  6. Kober L, et al. 2026 ESC guidelines for the management of heart failure. European Heart Journal. 2026; doi:10.1093/eurheartj/ehag100.
  7. Overview of heart failure. Merck Manual Professional Version. https://www.merckmanuals.com/en-ca/professional/cardiovascular-disorders/heart-failure/overview-of-heart-failure. Accessed Sept. 7, 2026.
  8. Managing heart failure symptoms. American Heart Association. https://www.heart.org/en/health-topics/heart-failure/warning-signs-of-heart-failure/managing-heart-failure-symptoms. Accessed Sept. 7, 2026.
  9. Planning for advanced heart failure. American Heart Association. https://www.heart.org/en/health-topics/heart-failure/living-with-heart-failure-and-managing-advanced-hf/planning-ahead-advanced-heart-failure. Accessed Sept. 7, 2026.
  10. Medical review (expert opinion). Mayo Clinic. Sept. 10, 2026.
  11. Walsh MN, et al. AHA/ACC/ESC/WHF expert consensus document: Second universal definition of heart failure (2026). Circulation. 2026; doi:10.1161/CIR.0000000000001455.
  12. Heidenreich PA, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure: A report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2022; doi:10.1161/CIR.0000000000001063.
  13. Mann DL, et al., eds. Clinical assessment of heart failure; Management of patients with heart failure. In: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. Elsevier; 2026. https://www.clinicalkey.com. Accessed Sept. 7, 2026.

Related

Associated Procedures

Left-sided heart failure