Dr. Kukafka discusses the NYHA heart failure classification system The New York Heart Association (NYHA) developed its initial heart failure classification system in 1928. Historically, the NYHA heart failure classification used a patient’s functional capacity to categorize patients. Patients were placed in one of four groups. Class I patients had no symptoms with ordinary physical activity and Class IV patients had symptoms with minimal activity or even at rest. Symptoms included angina, dyspnea, palpitations, and fatigue.
The NYHA heart failure classification system has been used to 1) gauge patients’ overall heart failure symptom burden, 2) follow patients’ status over time, 3) to monitor effects of therapeutic interventions, 4) to compare patients to one another, and 5) as a tool for perioperative risk assessment. For example, a NYHA functional class IV is listed among “active cardiac conditions for which the patient should undergo evaluation and treatment before noncardiac surgery” in the ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery, Class 1 LOE B. However this classification system may be inherently imprecise and is prone to significant interobserver variability.
In 1994, the NYHA heart failure classification system was further revised, which included a second category in addition to the patient’s functional capacity: objective assessment. Using data from electrocardiograms, stress tests, echocardiograms, and radiological imaging, patients were categorized into groups A through D, where group A patients had no objective evidence of cardiovascular disease and group D patients had objective evidence of severe cardiovascular disease.
Functional Capacity |
Objective Assessment |
Class I. Patients with cardiac disease but without resulting limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea, or anginal pain. |
A. No objective evidence of cardiovascular disease. |
Class II. Patients with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or anginal pain. |
B. Objective evidence of minimal cardiovascular disease. |
Class III. Patients with cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitations, dyspnea, or anginal pain. |
C. Objective evidence of moderately severe cardiovascular disease. |
Class IV. Patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of heart failure or the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased. |
D. Objective evidence of severe cardiovascular disease |
Examples of patient classification:
- Dyspnea at rest and a near total occlusion of the left main coronary artery: Functional Capacity IV, Objective Assessment D.
- Mild dyspnea while climbing stairs and a severe aortic stenosis: Functional Capacity II, Objective Assessment D.
- Angina at rest and angiographically normal coronary arteries: Functional Capacity IV, Objective Assessment A.
- No cardiac symptoms and a moderate pressure gradient across the mitral valve: Functional Capacity I, Objective Assessment C.
REFERENCES:
1) The Criteria Committee of the New York Heart Association. Nomenclature and Criteria for Diagnosis of Diseases of the Heart and Great Vessels. 9th ed. Boston, Mass: Little, Brown & Co; 1994:253-256.
2) Fleisher LA, et al: ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). Circulation. 2007;116.
3) Hunt SA, et al: ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): developed in collaboration with the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: endorsed by the Heart Rhythm Society. JACC, 2005;46;1-82.
Dr. Kukafka is a cardiac anesthesia fellow at UPENN