In order to provide optimal care for heart failure patients, it is essential for cardiologists to stratify the severity of an individual's disease state. Grouping heart failure into stages serves as a guide to the effectiveness of treatment by documenting the rate at which a given patient moves through the various levels of disease. The most commonly used heart failure stratification method is the New York Heart Association (NYHA) classification; however, other institutions, such as the American College of Cardiology (ACC), have created variations of this system to enhance its prognostic abilities.
History
The NYHA Heart Failure Classification, first published in 1928 and now in its ninth edition, stratifies patients based on subjective tests of functional capacity, or ability to expend energy, and an objective measures of the level of cardiovascular disease. In an effort to enhance treatment efforts and potentially stave off further development of heart failure, the ACC in conjunction with the American Heart Association, developed an additional classification system published in 2005. The ACC staging system focuses on the development and progression of heart failure and is to be used in addition to, rather than in place of, the NYHA classification. The newer system categorizes patients in stages of increasing severity from Stage A through Stage D.
Stage A
Patients falling into Stage A of the ACC Heart Failure Classification system include individuals that are at high risk for the development of heart failure, but that have no signs or symptoms of heart failure. These patients may have developed cardiovascular diseases such as high blood pressure, coronary artery disease or diabetes, but do not have any structural changes in the heart and have no functional limitations, such as increased fatigue with mild exertion.
Stage B
Unlike those in Stage A, Stage B patients do have structural damage to the heart. This can be the result of a heart attack which causes portions of the heart muscle to die, or could be the result of placing a large stress on the heart for an extended period of time as seen in patients with high blood pressure. These disease states cause the heart muscle to remodel itself and generally leads to enlarged heart chambers. While structural changes exist in Stage B patients, the individuals remain asymptomatic. Without a functional symptom such as shortness of breath and reduced exercise tolerance, these patients, like Stage A patients, do not have heart failure according to the NYHA classification.
The importance of recognizing the risk for patients in Stages A and B lies in the need to treat the underlying dysfunction prior to the development of heart failure.
Stage C
Stage C represents the majority of heart failure patients. These individuals have structural heart disease and are symptomatic. Individuals classified as Stage C will become short of breath on mild exertion, fatigue easily and have a noticeably reduced exercise tolerance. Treatment for these patients is much more extensive than for patients in Stages A and B and include additional medications and dietary restrictions. Stage C patients could require the use of pacemakers or implantable defibrillators to ensure adequate heart function.
Stage D
The ACC classification indicative of the most severe degree of heart failure is Stage D. These patients are symptomatic at rest even after receiving maximal therapeutic treatments. Stage D patients tend to be hospitalized regularly for complications resulting from the advanced degree of heart failure. Heart transplantation and permanent mechanical circulatory support are treatment options for individuals in Stage D. However, if extraordinary treatment measures are not employed, end-of-life care, such as hospice, should be considered.
References
- American Heart Association: 1994 Revisions to Classification of Functional Capacity and Objective Assessment of Patients With Diseases of the Heart
- "Journal of the American College of Cardiology"; 2009 Focused Update: ACCF/AHA Guidelines for the Diagnosis and Management of Heart Failure in Adults; Mariell Jessup, MD; 2009
